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Question 1
Correct
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A 30 year old female suffered from mismatched transfusion induced haemolysis. Which substance will be raised in the plasma of this patient?
Your Answer: Bilirubin
Explanation:Bilirubin is a yellow pigment that is formed due to the break down of RBCs. Haemolysis results in haemoglobin that is broken down into a haem portion and globin which is converted into amino acids and used again. Haem is converted into unconjugated bilirubin in the macrophages and shunted to the liver. In the liver it is conjugated with glucuronic acid making it water soluble and thus excreted in the urine. Its normal levels are from 0.2-1 mg/dl. Increased bilirubin causes jaundice and yellowish discoloration of the skin.
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This question is part of the following fields:
- General
- Physiology
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Question 2
Incorrect
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The bronchial circulation is a part of the circulatory system that supplies nutrients and oxygen to the pulmonary parenchyma. What percentage of cardiac output is received by bronchial circulation?
Your Answer: 30%
Correct Answer: 2%
Explanation:The bronchial circulation is part of the systemic circulation and receives about 2% of the cardiac output from the left heart. Bronchial arteries arise from branches of the aorta, intercostal, subclavian or internal mammary arteries. The bronchial arteries supply the tracheobronchial tree with both nutrients and O2. It is complementary to the pulmonary circulation that brings deoxygenated blood to the lungs and carries oxygenated blood away from them in order to oxygenate the rest of the body.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 3
Correct
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A 49-year-old man, smoker, complains of a persisting and worsening cough over the past few months. He also has noted blood in his sputum. The patient has no other major health conditions. Which of the following investigative procedures should be done first?
Your Answer: Sputum cytology
Explanation:Sputum cytology is a diagnostic test used for the examination of sputum under a microscope to determine if abnormal cells are present. It may be used as the first diagnostic procedure to help detect a suspected lung cancer or certain non-cancerous lung conditions.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 4
Incorrect
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A new-born was found to have an undeveloped spiral septum in the heart. This is characteristic of which of the following?
Your Answer: Atrioventricular septal defect
Correct Answer: Persistent truncus arteriosus
Explanation:Persistent truncus arteriosus is a congenital heart disease that occurs when the primitive truncus does not divide into the pulmonary artery and aorta, resulting in a single arterial trunk. The spiral septum is created by fusion of a truncal septum and the aorticopulmonary spiral septum. Incomplete development of these septa results in incomplete separation of the common tube of the truncus arteriosus and the aorticopulmonary trunk.
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This question is part of the following fields:
- Cardiovascular
- Pathology
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Question 5
Correct
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The thyroid gland is a large ductless gland located in which part of the neck?
Your Answer: Visceral space
Explanation:The thyroid gland is an endocrine gland in the neck, consisting of two lobes connected by an isthmus. It is situated at the front and sides of the neck in the visceral space.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 6
Correct
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After having donated a unit of blood. The blood bank will prefer to use which of the following anticoagulants to store the blood?
Your Answer: Citrate
Explanation:Calcium is necessary for coagulation to occur. Citrate being a chelator and combining with calcium ions to form un-ionised compound will prevent coagulation. Following transfusion the citrate is removed by the liver with in a few minutes. Oxalate also works on the same principle but it is toxic to the body.
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This question is part of the following fields:
- General
- Physiology
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Question 7
Correct
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Severe abdominal pain radiating to the back, along with increased serum amylase levels, is seen in which of the following conditions?
Your Answer: Pancreatitis
Explanation:The primary test for diagnosis and monitoring of pancreatitis is amylase. Increased plasma levels of amylase can be found in: salivary trauma (including anaesthetic intubation), mumps, pancreatitis and renal failure. However, a rise in the total amylase levels over 10 times the upper limit of normal (ULN) is suggestive of pancreatitis; 5–10 times the ULN may indicate ileus or duodenal disease or renal failure. Lower levels are commonly found in salivary gland disease.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 8
Correct
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An operation to resect a tumour of the right lung was stopped as the chest surgeon said that the tumour was crossing the oblique fissure. Which structures are separated by the oblique fissure of the right lung?
Your Answer: Lower lobe from both upper and middle lobes
Explanation:The oblique fissure on the right lung separates the lower lobe from both the middle and upper lobe. The lingual is only found on the left lung and is part of the upper lobe.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 9
Correct
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A 30-year old lady was admitted to the general surgical ward after a diagnosis of perforation of the first part of the duodenum that resulted from a long standing ulcer. If this perforation led to the expulsion of the gastric content that resulted to the erosion of an artery found in this part of the duodenum (the posterior of the first part of the duodenum). Which of the following arteries is this most likely to be?
Your Answer: Gastroduodenal
Explanation:The proximal part of the duodenum is supplied by the gastroduodenal artery. This artery is found descending behind the first part of the duodenum after branching from the hepatic artery. If gastric content was to be expelled in the posterior portion of the first part of the duodenum, then this artery would be most likely to be damaged. The common hepatic artery and the left gastric artery are branches of the coeliac trunk that are found superior to the duodenum. The proper hepatic artery is a branch of the common hepatic artery also found superior to the duodenum. The superior mesenteric artery is found behind the pancreas as a branch of the aorta that is at the bottom of the L1 level. The right gastric artery arises above the pylorus from the proper hepatic artery and supplies the lesser curvature of the stomach. The intestinal arteries supply the ileum and the jejunum.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 10
Correct
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A patient had sudden complete loss of vision of the right eye. Fundoscopy showed the distinct cherry red spot on the retina. Which of the following arteries was occluded?
Your Answer: Central artery of the retina
Explanation:The central retinal artery supplies all the nerve fibres that form the optic nerve, which carries the visual information to the lateral geniculate nucleus of the thalamus. Thus if the central retinal artery gets occluded, there is complete loss of vision in that eye and the entire retina (with the exception of the fovea) becomes pale, swollen and opaque while the central fovea still appears reddish (this is because the choroid colour shows through). This is the basis of the famous Cherry red spot seen on examination of the retina on fundoscopy of a central retinal artery occlusion (CRAO).
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 11
Incorrect
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A patient with a long standing lower motor neuron lesion will have:
Your Answer: Hyper-reflexia
Correct Answer: Muscle wasting
Explanation:Lower motor neurons (LMNs) connect the brainstem and spinal cord to muscle fibres. Damage to lower motor neurons is indicated by abnormal electromyographic potentials, fasciculations, paralysis, weakening and wasting of skeletal muscles.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 12
Correct
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Which organs would cause pain in a patient who complains of dull pain in her pelvis, along the midline starting from the pubic bone in the front to the sacrum at the back?
Your Answer: Urinary bladder, uterus/cervix/vagina, rectum
Explanation:The pain could have been caused by the urinary bladder, uterus/cervix/vagina or rectum as it involves the pelvic viscera.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 13
Incorrect
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Following a bee sting, a women develops a 2cm red, raised, swollen lesion at the site of the sting . Which of the following findings is likely to be seen in this lesion?
Your Answer: Neutrophilic migration
Correct Answer: Vasodilation
Explanation:Inflammation is the immediate response of the body towards infections or irritations. The cardinal signs of inflammation are 1. redness/rubor, 2. tumour/swelling, 3.dolar/pain, 4.calor/heat and organ dysfunction (function laesa). Inflammation has 2 components; vascular and cellular. Blood vessels dilate upstream of the inflamed area leading to the rubor and calor and constrict downstream, increasing pressure and causing fluid to leak out of the capillary, resulting in swelling. The cellular component includes infiltration by neutrophils. Leukocyte arrival and functions include; 1. margination: cells marginated from the centre to the periphery of the vessel, 2. rolling: selectins are upregulated on the vessel walls, 3. adhesion: upregulation of the adhesion molecules ICAM and VCAM on the endothelium interact with integrins on the leukocytes resulting in adhesion, 4. diapedesis and chemotaxis: diapedesis is the transmigration of the leukocyte across the endothelium of the capillary and towards a chemotactic product and 5. phagocytosis: engulfing the offending substance/cell.
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This question is part of the following fields:
- Inflammation & Immunology
- Pathology
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Question 14
Correct
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A child defecates a few minutes after being fed by the mother. This is most likely due to:
Your Answer: Gastrocolic reflex
Explanation:The gastrocolic reflex is a physiological reflex that involves increase in colonic motility in response to stretch in the stomach and by-products of digestion in the small intestine. It is shown to be uneven in its distribution throughout the colon, with the sigmoid colon affected more than the right side of the colon in terms of a phasic response. Various neuropeptides have been proposed as mediators of this reflex, such as serotonin, neurotensin, cholecystokinin and gastrin.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 15
Incorrect
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A 17-year-old female was given an antibiotic for a urinary tract infection. After taking the medication the patient developed Steven-Johnson syndrome. Which particular antibiotic usually causes Steven-Johnson syndrome?
Your Answer: Erythromycin
Correct Answer: Sulphonamides
Explanation:Stevens–Johnson syndrome (SJS) is a type of severe skin reaction. The most common cause is certain medications such as lamotrigine, carbamazepine, allopurinol, sulphonamide antibiotics, and nevirapine.
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 16
Correct
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Tumours derived from all three germ-cell layers in new-borns usually occur in which of the following sites?
Your Answer: Sacrococcygeal area
Explanation:A teratoma is a tumour with tissue or organ components resembling normal derivatives of more than one germ layer. It is derived from all three cell layers. The most common location of teratoma in new-born infants is in the sacrococcygeal area.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 17
Incorrect
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A 45-year-old man complains of shortness of breath, cough and chest pain. Chest X ray revealed a perihilar mass with bronchiectasis in the left mid-lung. Which of the following is most probably associated with these findings?
Your Answer: Pulmonary hamartoma
Correct Answer: Bronchial carcinoid
Explanation:Bronchial carcinoids are neuroendocrine tumours that arise from Kulchitsky’s cells of the bronchial epithelium. Kulchitsky’s cells belong to the diffuse endocrine system. Patients affected by this tumour may be asymptomatic or may present with symptoms of airway obstruction, like dyspnoea, wheezing, and cough. Other common findings are recurrent pneumonia, haemoptysis, chest pain and paraneoplastic syndromes. Chest radiographs are abnormal in the majority of cases. Peripheral carcinoids usually present as a solitary pulmonary nodule. For central lesions common findings include hilar or perihilar masses with or without atelectasis, bronchiectasis, or consolidation. Bronchial carcinoids most commonly arise in the large bronchi causing obstruction.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 18
Correct
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Which tumour occurs in young adults, affecting the epiphyses of the bones and sometimes extending to the soft tissues?
Your Answer: Benign giant-cell tumour
Explanation:Benign giant-cell tumours tend to affect adults in their twenties and thirties, occur in the epiphyses and can erode the bone and extend into the soft tissues. These tumours have a strong tendency to recur.
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 19
Correct
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The normal location of the major duodenal papilla:
Your Answer: Descending part of the duodenum
Explanation:The major duodenal papilla is on the descending portion of the duodenum on the medial side, about 7-10cm from the pylorus. The pancreatic ducts and the common bile ducts unite and open by a common orifice on the summit of the duodenal papilla.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 20
Correct
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Vincristine is a chemotherapy agent used to treat a number of types of cancer. Which of the following is a recognised major side-effect of vincristine?
Your Answer: Peripheral neuropathy
Explanation:Vincristine is an alkaloid chemotherapeutic agent. It is used to treat a number of types of cancer including acute lymphocytic leukaemia, acute myeloid leukaemia, Hodgkin’s disease, neuroblastoma, and small cell lung cancer among others. The main side-effects of vincristine are peripheral neuropathy and constipation.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 21
Incorrect
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Dicloxacillin is an antibiotic; the subclass that dicloxacillin belongs to is:
Your Answer: Tetracycline
Correct Answer: Penicillin
Explanation:Dicloxacillin is a narrow-spectrum beta-lactam antibiotic. It is used to treat infections caused by susceptible Gram-positive bacteria and most effective against beta-lactamase-producing organisms such as Staphylococcus aureus. To decrease the development of resistance, dicloxacillin is recommended to treat infections that are suspected or proven to be caused by beta-lactamase-producing bacteria.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 22
Correct
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A 7-year-old girl is given cephalexin to treat an infection and develops hives, with localised facial oedema. Which of the following conditions will cause localised oedema?
Your Answer: Angio-oedema
Explanation:Angio-oedema, is the rapid swelling of the skin, mucosa and submucosal tissues. The underlying mechanism typically involves histamine or bradykinin. The version related to histamine is to due an allergic reaction to agents such as insect bites, food, or medications. The version related to bradykinin may occur due to an inherited C1 esterase inhibitor deficiency, medications e.g. angiotensin converting enzyme inhibitors, or a lymphoproliferative disorder.
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This question is part of the following fields:
- Physiology
- Renal
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Question 23
Correct
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A 50 year old male point was diagnosed with tennis elbow that became worse after he started playing basket ball over the last three months. He was admitted to the orthopaedic ward to have elbow braces fitted. What type of synovial joint is the elbow joint?
Your Answer: Hinge
Explanation:The elbow joint is one of the many synovial joints in the body. This joint is an example of the hinge joint as the humerus is received into the semilunar notch of the ulna and the capitulum of the humerus articulates with the fovea on the head of the radius, together acting as a hinge in one plane.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 24
Correct
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The blood-brain barrier is a membrane that separates the circulating blood from the brain extracellular fluid in the central nervous system (CNS). Which of the following statements regarding the blood– brain barrier is CORRECT?
Your Answer: It breaks down in areas of brain that are infected
Explanation:The blood–brain barrier is a membrane that controls the passage of substances from the blood into the central nervous system. It is a physical barrier between the local blood vessels and most parts of the central nervous system and stops many substances from travelling across it. During meningitis, the blood–brain barrier may be disrupted. This disruption may increase the penetration of various substances (including either toxins or antibiotics) into the brain. A few regions in the brain, including the circumventricular organs, do not have a blood–brain barrier.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 25
Correct
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A blood sample from a patient with polycythaemia vera will show which of the following abnormalities?
Your Answer: High platelet count
Explanation:Polycythaemia is a condition that results in an increase in the total number of red blood cells (RBCs) in the blood. It can be due to a myeloproliferative syndrome, chronically low oxygen levels or rarely malignancy. In primary polycythaemia/ polycythaemia vera the increase is due to an abnormality in the bone marrow, resulting in increased RBCs, white blood cells (WBCs) and platelets. In secondary polycythaemia the increase occurs due to high levels of erythropoietin either artificially or naturally. The increase is about 6-8 million/cm3 of blood. A type of secondary polycythaemia is physiological polycythaemia where people living in high altitudes who are exposed to hypoxic conditions produce more erythropoietin as a compensatory mechanism for thin oxygen and low oxygen partial pressure.
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This question is part of the following fields:
- General
- Physiology
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Question 26
Correct
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A biopsy taken from the respiratory passage of a 37 year old male, chronic smoker will mostly likely show which cellular adaptation?
Your Answer: Stratified squamous metaplasia
Explanation:Metaplasia is a change in the cell type caused in part due to an extrinsic stress on the organ. It involves a change in the surface epithelium from one cell type to the another, most commonly squamous to columnar. This is a reversible process, and removal of the stress should theoretically reverse the surface epithelium back to normal morphology. Respiratory tract metaplasia is a classic example, in which the normal pseudostratified columnar epithelium is replaced by stratified squamous epithelium to better cope with the stress. Under continuous stress metaplasia can progress to dysplasia which is a disordered growth of cells eventually leading to the development of carcinoma.
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This question is part of the following fields:
- Cell Injury & Wound Healing; Respiratory
- Pathology
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Question 27
Correct
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Which of the following associations is correctly matched with the body's defence mechanism in fighting infection?
Your Answer: Specific cellular mechanism → cytotoxic T cells
Explanation:The immune system has certain levels of defence against pathogens. First line includes simple barriers such as skin, mucosa and stomach acid that prevent the pathogen from entering into the body. If this barrier is breached then the innate immune system is activated which includes leukocytes (macrophages, neutrophils, mast cells, eosinophils, basophils, natural killer cells). If the pathogens invade the second layer of defence then the third layer, adaptive immunity is activated, which includes B and T lymphocytes. B cells provide a humoral response whereas cytotoxic T cells have specific cellular mechanisms. They maintain a memory of past infections and are activated faster following a recurrence.
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This question is part of the following fields:
- General
- Physiology
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Question 28
Correct
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Which of the following is the source of blood supply to the artery of the round ligament at the head of the femur?
Your Answer: Obturator artery
Explanation:The posterior branch of the obturator artery provides an articular branch to the head of the femur.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 29
Correct
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A 43-year-old diabetic man complains of headaches, palpitations, anxiety, abdominal pain and weakness. He is administered sodium bicarbonate used to treat:
Your Answer: Metabolic acidosis
Explanation:Sodium bicarbonate is indicated in the management of metabolic acidosis, which may occur in severe renal disease, uncontrolled diabetes, circulatory insufficiency due to shock or severe dehydration, extracorporeal circulation of blood, cardiac arrest and severe primary lactic acidosis. Bicarbonate is given at 50-100 mmol at a time under scrupulous monitoring of the arterial blood gas readings. This intervention, however, has some serious complications including lactic acidosis, and in those cases, should be used with great care.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 30
Correct
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What is the action of the muscle of the orbit that originates on the lesser wing of the sphenoid bone, just above the optic foramen?
Your Answer: Elevation of the upper eyelid
Explanation:The levator palpebrae superioris is the muscle in the orbit that elevates the superior (upper) eyelid. The levator palpebrae superioris originates on the lesser wing of the sphenoid bone, just above the optic foramen and receives somatic motor input from the ipsilateral superior division of the oculomotor nerve.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 31
Correct
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A 32-year-old man presented with a metabolic acidosis and increased anion gap. What is the most likely cause of the changes of the anion gap in this patient?
Your Answer: Lactic acidosis
Explanation:High anion gap in metabolic acidosis is caused generally by the elevation of the levels of acids like ketones, lactate, sulphates in the body, which consume the bicarbonate ions. Other causes of a high anion gap include overdosing on salicylates, uraemia, rhabdomyolysis, hypocalcaemia, hypomagnesaemia, or ingestion of toxins such as ethylene glycol, methanol, propyl alcohol, cyanide and iron.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
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Question 32
Incorrect
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A 56 year old gentleman, who is a chronic smoker presents to the clinic with dyspnoea. His Chest X-ray shows intercostal space widening with increased blackening bilaterally. What is the most likely finding on his pulmonary function test?
Your Answer: Decreased residual volume
Correct Answer: Increased total lung capacity
Explanation:In patients suspected of having chronic obstructive pulmonary disease, pulmonary function testing (PFT) is useful to confirm airway obstruction, to quantify its severity and reversibility, for following disease progression and monitoring response to treatment. These tests include:
FEV1 – volume of air forcefully expired during the first second after a full breath
Forced vital capacity (FVC) – total volume of air expired with maximal force and flow-volume loops. The hallmark of airway obstruction is reduction of FEV1, FVC and the ratio of FEV1/FVC, with a concave pattern in expiratory tracing on the flow-volume loop. FEV1 and forced vital capacity (FVC) are easily measured with office spirometry and are useful to assess the severity of disease. Other parameters include increased total lung capacity, functional residual capacity and residual volume, which can help distinguish chronic obstructive pulmonary disease (COPD) from restrictive pulmonary disease where these values are lower than normal. Along with these, other tests are decreased vital capacity; and decreased diffusing capacity for carbon monoxide (DLCO). DLCO is non-specific and can be low in other disorders that affect the pulmonary vascular bed, such as interstitial lung disease. DLCO is however useful to distinguish COPD from asthma, in which DLCO is normal or elevated.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 33
Correct
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A man was stabbed in the thigh following a bar brawl. A superficial vein was injured which terminates in the femoral vein. This superficial vein is?
Your Answer: Great saphenous
Explanation:The great saphenous vein is considered the longest vein in the body. It terminates in the femoral vein nearly 3cm below the inguinal ligament. It begins at the dorsum of the foot in the medial marginal vein and ascends at the medial side of the leg in relation with the saphenous nerve.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 34
Incorrect
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Cancer of the testis most likely metastases to which set of lymph nodes?
Your Answer: Superficial inguinal
Correct Answer: Aortic
Explanation:The lymphatic drainage of an organ is related to its blood supply. The lymphatic drainage of the testis drains along the testicular artery to reach the lymph nodes along the aorta.
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This question is part of the following fields:
- Endocrine
- Pathology
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Question 35
Incorrect
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A 34-year old gentleman presented with acute pancreatitis to the emergency department. On enquiry, there was found to be a history of recurrent pancreatitis, eruptive xanthomas and raised plasma triglyceride levels associated with chylomicrons. Which of the following will be found deficient in this patient?
Your Answer: High-density lipoprotein (HDL)
Correct Answer: Lipoprotein lipase
Explanation:The clinical features mentioned here suggest the diagnosis of hypertriglyceridemia due to lipoprotein lipase (LPL) deficiency. LPL aids in hydrolysing the lipids in lipoproteins into free fatty acids and glycerol. Apo-CII acts as a co-factor. Deficiency of this enzyme leads to hypertriglyceridemia.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 36
Incorrect
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The wound healing process is documented in patients undergoing laparoscopic procedures. The port incisions are sutured closed and the wounds observed every few weeks for re-epithelialisation and tensile strength. Which substance is mostly likely to be found at a cellular level involved in wound healing?
Your Answer: Collagen
Correct Answer: Tyrosine kinase
Explanation:Cell surface growth factor receptors require intercellular proteins such as tyrosine kinase which are necessary to initiate a series of events that eventually lead to cell division and growth. Tyrosine kinase is an enzyme that transfers a phosphate group to the tyrosine residue in a protein. This phosphorylation will lead to an up regulation of the enzyme activity.
Fibronectin acts in the extracellular matrix to bind macromolecules (such as proteoglycans) via integrin receptors to aid attachment and migration of cells.
Laminin is an extracellular matrix component that is abundant in basement membranes.
Hyaluronic acid is one of the proteoglycans in the extracellular matrix.
Collagen fibres are part of the extracellular matrix that gives strength and stability to connective tissues.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 37
Correct
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A 60 year old patient with a history of carcinoma of the head of the pancreas, and obstructive jaundice presents with a spontaneous nose bleed and easy bruising. What is the most likely reason for this?
Your Answer: Vitamin-K-dependent clotting factors deficiency
Explanation:Vitamin K is a fat soluble vitamin requiring fat metabolism to function properly to allow for its absorption. People with obstructive jaundice develop vitamin k deficiency as fat digestion is impaired. Vit K causes carboxylation of glutamate residue and hence regulates blood coagulation including: prothrombin (factor II), factors VII, IX, X, protein C, protein S and protein Z.
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This question is part of the following fields:
- General
- Physiology
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Question 38
Correct
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Which of the following is NOT a Gram-negative rod?
Your Answer: Clostridium tetani
Explanation:Gram-positive rods include Clostridia, Listeria and diphtheroids.
Gram-negative rods include Escherichia coli, Klebsiella, Yersinia, Haemohilus, Pseudomonas, Shigella, Legionella, proteus and Salmonella
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 39
Incorrect
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A patient came into the emergency in a state of shock. His blood group is not known, but on testing it clotted when mixed with Type A antibodies. Which blood should be transfused?
Your Answer: A-ve
Correct Answer: B +ve
Explanation:There are two stages to determine the blood group, known as ABO typing. The first stage is called forward typing. In this method, RBCs are mixed with two separate solutions of type A or type B antibodies to see if they agglutinate. If this blood clumps, this indicates the presence of antigens within the blood sample. For example, a sample of type B blood will clump when tested with type A antibodies as it contains type B antigens. Group B – has only the B antigen on red cells (and A antibody in the plasma)
Group B – has only the B antigen on red cells (and A antibody in the plasma)
Group AB – has both A and B antigens on red cells (but neither A nor B antibody in the plasma)
Group O – has neither A nor B antigens on red cells (but both A and B antibody are in the plasma). Many people also have a Rh factor on the red blood cell’s surface. This is also an antigen and those who have it are called Rh+. Those who have not are called Rh–. A person with Rh– blood does not have Rh antibodies naturally in the blood plasma (as one can have A or B antibodies, for instance) but they can develop Rh antibodies in the blood plasma if they receive blood from a person with Rh+ blood, whose Rh antigens can trigger the production of Rh antibodies. A person with Rh+ blood can receive blood from a person with Rh– blood without any problems. The patient’s blood group is B positive as he has antigen B, antibody A and Rh antigens.
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This question is part of the following fields:
- General
- Physiology
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Question 40
Correct
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Point of entry of the vagal trunk into the abdomen:
Your Answer: Oesophageal hiatus
Explanation:The oesophageal hiatus is located in the muscular part of the diaphragm a T10 and is above, in front and a little to the left of the aortic hiatus. It transmits the oesophagus, the vagus nerves and some small oesophageal arteries.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 41
Correct
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At which cervical level does the common carotid artery bifurcate into the internal and external carotid arteries?
Your Answer: C4
Explanation:The common carotid arteries are present on the left and right sides of the body. These arteries originate from different sources, but follow symmetrical courses. The right common carotid originates in the neck from the brachiocephalic trunk; the left from the aortic arch in the thorax. These split into the external and internal carotid arteries at the upper border of the thyroid cartilage, at around the level of the fourth cervical vertebra.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 42
Incorrect
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A medical student is told a substance is freely filtered but is not metabolised, secreted, or stored in the kidney. It has a plasma concentration of 1000 mg/l and its urine excretion rate is 25 mg/min, and the inulin clearance is 100 ml/min. What is the rate of tubular reabsorption of the substance?
Your Answer: 25 mg/min
Correct Answer: 75 mg/min
Explanation:Reabsorption or tubular reabsorption is the process by which the nephron removes water and solutes from the tubular fluid (pre-urine) and returns them to the circulating blood. To calculate the reabsorption rate of substance Z we use the following equation: excretion = (filtration + secretion) – reabsorption. As this substance is freely filtered, its filtration rate is equal to that of inulin. So 25 = (100 + 0) – reabsorption. Reabsorption = 100 – 25 therefore reabsorption = 75 mg/min.
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This question is part of the following fields:
- Physiology
- Renal
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Question 43
Correct
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For calculation of cardiac output by Fick's principle, which of the following vessels is the best source of venous blood to determine the arterial-to-venous oxygen tension difference?
Your Answer: Pulmonary artery
Explanation:Fick’s principle states that the total uptake (or release) of a substance by peripheral tissues is equal to the product of the blood flow to the peripheral tissues and the arterial– venous concentration difference (gradient) of the substance. It is used to measure the cardiac output, and the formula is Cardiac output = oxygen consumption divided by arteriovenous oxygen difference. Assuming there are no shunts across the pulmonary system, the pulmonary blood flow equals the systemic blood flow. The arterial and venous blood oxygen content is measured by sampling from the pulmonary artery (low oxygen content) and pulmonary vein (high oxygen content). Peripheral arterial blood is used as a surrogate for the pulmonary vein.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 44
Incorrect
-
The midgut loop, also called the primary intestinal loop in a developing embryo, is formed when the midgut bends around which of the following arteries?
Your Answer: Coeliac trunk
Correct Answer: Superior mesenteric
Explanation:In a developing foetus, the midgut develops to form most of the intestines. During this development process, the midgut usually bends around the superior mesenteric artery and forms what is referred to as the midgut loop.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 45
Correct
-
Diuretics that act on the ascending limb of the loop of Henle produce:
Your Answer: Reduced active transport of sodium
Explanation:The loop of Henlé leads from the proximal convoluted tubule to the distal convoluted tubule. Its primary function uses a counter current multiplier mechanism in the medulla to reabsorb water and ions from the urine. It can be divided into four parts:
1. Descending limb of loop of Henl̩ Рlow permeability to ions and urea, while being highly permeable to water
2. Thin ascending limb of loop of Henl̩ Рnot permeable to water, but it is permeable to ions
3. Medullary thick ascending limb of loop of Henlé – sodium (Na+), potassium (K+) and chloride (Cl–) ions are reabsorbed by active transport. K+ is passively transported along its concentration gradient through a K+ channel in the basolateral aspect of the cells, back into the lumen of the ascending limb.
4. The cortical thick ascending limb – the site of action where loop diuretics such as furosemide block the K+/Na+/2Cl− co-transporters = reduced active transport.
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This question is part of the following fields:
- Physiology
- Renal
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Question 46
Correct
-
From which source does the lingual artery originate?
Your Answer: External carotid
Explanation:The lingual artery arises from the external carotid between the superior thyroid artery and facial artery. It can be located easily on the lower surface of the tongue. The terminal branch of the lingual artery is the deep lingual artery. On its course the lingual artery gives off side branches: dorsal lingual branches that supply the dorsum of the tongue till the epiglottis; sublingual artery that supplies the sublingual gland.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 47
Correct
-
A 60-year old patient having a history of cholelithiasis that led to recurrent pain, bloating, nausea and vomiting, was scheduled for surgery to have the gallbladder removed. During the cholecystectomy, the registrar conducting the procedure accidentally punctured a blood vessel that lies immediately posterior to the omental foramen and blood filled the operating field. Which of the following blood vessels was likely punctured?
Your Answer: Inferior vena cava
Explanation:The omental foramen is the pathway that connects the greater peritoneal sac and the lesser peritoneal sac. The omental foramen is bordered posteriorly by the inferior vena cava. This is the blood vessel that would most likely be punctured.
The aorta and its branch, the renal artery, lie postero-lateral to the omental foramen and are deeper than the inferior vena cava hence making them less likely to be injured.
The hepatic portal vein, the hepatic artery and the superior mesenteric vein borders the omental foramen anteriorly and would not be injured by a jab on the posterior border of the omental foramen.
Finally, the splenic artery is found in the splenorenal ligament that borders the omental foramen laterally to the left.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 48
Correct
-
Which nuclei of the posterior grey column of the spinal cord are likely affected in a patient who has lost the sensation of pain and temperature?
Your Answer: Substantia gelatinosa
Explanation:Substantia gelatinosa is one of the nuclei in the posterior grey column along side other posterior grey column nuclei like the nucleus dorsalis, nucleus proprius, and posteromarginal nucleus. These nuclei are a collection of cells in the posterior grey area found in throughout the spinal cord. The substantia gelatinosa receives direct input from the dorsal nerve roots (sensory), especially from thermoreceptors and nociceptors (receptors for temperature and pain).
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This question is part of the following fields:
- Anatomy
- Neurology
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Question 49
Incorrect
-
Which of the following proteins prevents red blood cells (RBCs) from bursting when they pass through capillaries?
Your Answer: Integrin
Correct Answer: Spectrin
Explanation:Spectrin is a structural protein found in the cytoskeleton that lines the intercellular side of the membrane of cells which include RBCs. They maintain the integrity and structure of the cell. It is arranged into a hexagonal arrangement formed from tetramers of spectrin and associated with short actin filaments that form junctions allowing the RBC to distort its shape.
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This question is part of the following fields:
- General
- Physiology
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Question 50
Correct
-
A teenage Somalian boy presents with a complaint of an enlarged lower jaw. His blood film shows blast cells and macrophages. Which virus is responsible for this?
Your Answer: Epstein–Barr virus
Explanation:Burkitt’s lymphoma is a type of non-Hodgkin’s lymphoma. Histologically it is characterised by a starry sky appearance due to numerous neoplastic macrophages which are required to clear the rapidly dividing tumour cells/blast cells. Burkitt’s lymphoma commonly affects the jaw bone, forming a huge tumour mass. It is associated with translocation of c-myc gene and has three types: 1) endemic/African type, 2)sporadic and 3)immunodeficiency-associated. The first type is strongly associated with EBV.
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This question is part of the following fields:
- General
- Physiology
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Question 51
Correct
-
A 55-year old lady underwent a major surgery for repair of an aortic aneurysm. Her blood pressure was low throughout the intra-operative and the post-operative period, along with increasing serum creatinine and urea. Microscopic examination of her urine showed multiple granular and hyaline casts. What is the likely condition the patient is suffering from?
Your Answer: Acute tubular necrosis
Explanation:The most common predisposing factor leading to acute tubular necrosis is ischemia, typically seen in hospitalized patients with low blood pressure.
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This question is part of the following fields:
- Pathology
- Renal
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Question 52
Incorrect
-
A 13-year-old girl has complained of pain in her left arm for 4 months. An X-ray reveals a mass along with erosion of the affected humerus. Histologically, the tumour is found to be formed by small, round, blue cells. What is the most likely diagnosis?
Your Answer: Chondroblastoma
Correct Answer: Ewing’s sarcoma
Explanation:Ewing’s sarcoma is formed by small, round, blue cells, and is common in children. The usually develop in limbs, and clinical findings include pain and inflammation, with lytic destruction showing up on X-rays.
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 53
Correct
-
Some substances, such as Chromium-51 and Technetium-99, are freely filtered but not secreted or absorbed by the kidney. In these cases, their clearance rate is equal to:
Your Answer: Glomerular filtration rate
Explanation:If a substance passes through the glomerular membrane with perfect ease, the glomerular filtrate contains virtually the same concentration of the substance as does the plasma and if the substance is neither secreted nor reabsorbed by the tubules, all of the filtered substance continues on into the urine. Glomerular filtration rate (GFR) describes the flow rate of filtered fluid through the kidney.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 54
Incorrect
-
A 35-year-old ultra marathon runner becomes severely dehydrated and collapses. This patient most likely has:
Your Answer: Low plasma ADH levels
Correct Answer: Decreased baroreceptor firing rate
Explanation:Baroreceptors are sensors located in the blood vessels of all vertebrate animals. They sense the blood pressure and relay the information to the brain, so that a proper blood pressure can be maintained. Acute dehydration results in decreased plasma volume and increased plasma osmolarity, since more water than salt is lost in sweat. The decrease in plasma volume leads to an inhibition of the baroreceptors and a lower firing rate. The increase in plasma osmolarity leads to increased ADH secretion and high plasma ADH levels, which increases water permeability of collecting duct cells. Therefore more water is reabsorbed by the kidneys and renal water excretion is low.
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This question is part of the following fields:
- Physiology
- Renal
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Question 55
Correct
-
A 25-year-old female had a painful abdomen and several episodes of vomiting. She was severely dehydrated when she was brought to the hospital. Her ABG showed a pH 7.7, p(O2) 75 mmHg, p(CO2) 46 mmHg and bicarbonate 48 mmol/l. The most likely interpretation of this ABG report would be:
Your Answer: Metabolic alkalosis
Explanation:Metabolic alkalosis is a primary increase in bicarbonate (HCO3−) with or without compensatory increase in carbon dioxide partial pressure (Pco2); pH may be high or nearly normal. Metabolic alkalosis occurs as a consequence of a loss of H+ from the body or a gain in HCO3 -. In its pure form, it manifests as alkalemia (pH >7.40). As a compensatory mechanism, metabolic alkalosis leads to alveolar hypoventilation with a rise in arterial carbon dioxide tension p(CO2), which diminishes the change in pH that would otherwise occur. Normally, arterial p(CO2) increases by 0.5–0.7 mmHg for every 1 mmol/l increase in plasma bicarbonate concentration, a compensatory response that occurs very rapidly. If the change in p(CO2) is not within this range, then a mixed acid–base disturbance occurs. Likewise, if the increase in p(CO2) is less than the expected change, then a primary respiratory alkalosis is also present. However an elevated serum bicarbonate concentration can also occur due to a compensatory response to primary respiratory acidosis. A bicarbonate concentration greater than 35 mmol/l is almost always caused by metabolic alkalosis (as is the case in this clinical scenario). Calculation of the serum anion gap can also help to differentiate between primary metabolic alkalosis and the metabolic compensation for respiratory acidosis. The anion gap is frequently elevated to a modest degree in metabolic alkalosis because of the increase in the negative charge of albumin and the enhanced production of lactate. However, the only definitive way to diagnose metabolic alkalosis is by performing a simultaneous blood gases analysis, which reveals elevation of both pH and arterial p(CO2) and increased calculated bicarbonate.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
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Question 56
Correct
-
The petrous part of the internal carotid artery is located inside of which cranial bone?
Your Answer: Temporal
Explanation:The petrous segment, or C2, of the internal carotid is that which is inside the petrous part of the temporal bone. This segment extends until the foramen lacerum. The petrous portion classically has three sections: an ascending, or vertical portion; the genu, or bend; and the horizontal portion.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 57
Correct
-
Dysarthria, nystagmus and a tremor worsening with directed movement are likely to be seen in:
Your Answer: Cerebellar disease
Explanation:The given symptoms are seen in diseases affecting the cerebellum. A cerebellar tremor is a slow tremor that occurs at the end of a purposeful movement. It is seen in cerebellar disease, such as multiple sclerosis or some inherited degenerative disorders and chronic alcoholism. Classically, tremors are produced in the same side of the body as a one-sided lesion. Cerebellar disease can also result in a wing-beating’ type of tremor called rubral or Holmes’ tremor – a combination of rest, action and postural tremors. Other signs of cerebellar disease include dysarthria (speech problems), nystagmus (rapid, involuntary rolling of the eyes), gait problems and postural tremor of the trunk and neck.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 58
Incorrect
-
T lymphocytes that express the MCH type II antigen are most likely to produce which of the following cytokines?
Your Answer: Tumour necrosis factor
Correct Answer: Gamma interferon
Explanation:Interferon gamma is a soluble cytokine previously known as the macrophage activating factor. It is the only member belonging to the type II class of the interferons. It is secreted by a number of cells taking part in the immune reaction including: T-helper cells (CD-4), cells with immunological memory (CD45PA), killer cells (CD8), dendrite cells (CD23,35), natural killer cells (CD16) and B lymphocytes (CD22,CD23). It has both a defending as well as a pathological effect. It induces differentiation in the myeloid cell in the bone marrow. If macrophages are infected by parasites it activates the macrophages to destroy them. IFN-γ strengthens the anti-tumour activities of the cytotoxic lymphocytes. Together with CD4 or CD8 toxins, produced by lymphocytes, it suppresses the growth of the tumour cells. along with these functions it increases the non specific response of the natural killer cells, causing changes in the cell membrane surface to prevent adhesion and penetration of a virus. It can either increase or decrease B cell response and it activates osteoclasts which increases bone resorption.
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This question is part of the following fields:
- Inflammation & Immunology
- Pathology
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Question 59
Correct
-
The rotator cuff surrounds the shoulder joint and consists of the supraspinatus, infraspinatus, subscapularis and which one other muscle?
Your Answer: Teres minor
Explanation:The correct answer is the teres minor muscle. These group of muscles play an important role in protecting the shoulder joint and keeping the head of the humerus in the glenoid fossa of the scapula. This fossa is somehow shallow and needs support to allow for the full mobility that the shoulder joint has.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 60
Incorrect
-
What best describes the muscles of the posterior compartment of the leg?
Your Answer: A-It crosses two joints
Correct Answer: One of the posterior compartment leg muscles laterally rotates the femur
Explanation:The muscles of the back of the leg are subdivided into two groups: superficial and deep. Superficial muscles include gastrocnemius, soleus and plantaris and are the chief extensors of the foot at the ankle joint. Deep muscles include the tibialis posterior, flexor hallucis longus, flexor digitorum longus and popliteus
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 61
Correct
-
A young man came to the emergency room after an accident. The anterior surface of his wrist was lacerated with loss of sensation over the thumb side of his palm. Which nerves have been damaged?
Your Answer: Median
Explanation:The median nerve provides cutaneous innervation to the skin of the palmar radial three and a half fingers. Also the site of injury indicates that the medial nerve may have been injured as it passes into the hand by crossing over the anterior wrist.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 62
Correct
-
Injury to this nerve may result in loss of sensation of the mandibular teeth and bone:
Your Answer: Inferior alveolar nerve
Explanation:The inferior alveolar nerve (sometimes called the inferior dental nerve) is a branch of the mandibular nerve, which is itself the third branch of the trigeminal nerve. The inferior alveolar nerves supply sensation to the lower teeth of the mandible.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 63
Correct
-
A patient is diagnosed with Conn’s syndrome. Aldosterone is secreted from where?
Your Answer: Zona glomerulosa of the adrenal cortex
Explanation:The adrenal gland comprises an outer cortex and an inner medulla, which represent two developmentally and functionally independent endocrine glands.
The adrenal medulla secretes adrenaline (70%) and noradrenaline (30%)
The adrenal cortex consists of three layers (remembered by the mnemonic GFR):
G = zona glomerulosa – secretes aldosterone
F = zona fasciculata – secretes cortisol and sex steroids
R = zona reticularis – secretes cortisol and sex steroids.
Aldosterone facilitates the reabsorption of sodium and water and the excretion of potassium and hydrogen ions from the distal convoluted tubule and collecting ducts. Conn’s syndrome is characterized by increased aldosterone secretion from the adrenal glands.
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This question is part of the following fields:
- Endocrine
- Physiology
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Question 64
Correct
-
A 60-year-old female has sudden onset of high-grade fever associated with cough with productive rusty-coloured sputum. Chest x-ray showed left-sided consolidation. What is the most accurate test for the diagnosis of this patient?
Your Answer: Sputum culture
Explanation:Sputum culture is used to detect and identify the organism that are infecting the lungs or breathing passages.
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 65
Incorrect
-
 A 45-year-old man presented to the doctor complaining of a flank pain and episodes of haematuria. Abdominal ultrasound revealed a left renal mass and the patient underwent a nephrectomy. Histopathological pattern was triphasic with blastemal, epithelial, and stromal components. The pathologist suggested the tumour resulted from the lack of a tumour suppressor gene on chromosome 11. Which of the following tumours is the pathologist most likely suggesting?
Your Answer: Renal cell carcinoma
Correct Answer: Wilms’ tumour
Explanation:Wilms’ tumour is one of the most common malignant tumours of childhood but it can also rarely be found in adults. In biopsy, classical histopathological findings include the triphasic pattern composed by blastemal, epithelial, and stromal elements. First symptoms in children include an abdominal palpable mass, while in adults pain and haematuria are the most common complaints. Deletions of tumours’ suppressor genes on chromosome 11 are usually associated with Wilms’ tumour.
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This question is part of the following fields:
- Pathology
- Renal
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Question 66
Correct
-
A 12-year old girl was brought to the hospital with recurrent headaches for 6 months. Her physical examination revealed no abnormality. A CT scan of the head revealed a suprasellar mass with calcifications, eroding the surrounding sella turcica. The lesion is likely to represent:
Your Answer: Craniopharyngioma
Explanation:Craniopharyngiomas (also known as Rathke pouch tumours, adamantinomas or hypophyseal duct tumours) affect children mainly between the age of 5 and 10 years. It constitutes 9% of brain tumours affecting the paediatric population. These are slow-growing tumours which can also be cystic, and arise from the pituitary stalk, specifically the nests of epithelium derived from Rathke’s pouch. Histologically, this tumour shows nests of squamous epithelium which is lined on the outside by radially arranged cells. Calcium deposition is often seen with a papillary type of architecture.
ACTH-secreting pituitary adenomas are rare and mostly microadenomas. Paediatric astrocytoma’s usually occur in the posterior fossa. Although null cell adenomas can cause mass effect and give rise to the described symptoms, they are not suprasellar. Prolactinomas can also show symptoms of headache and disturbances in the visual field, however they are known to be small and slow-growing.
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This question is part of the following fields:
- Endocrine
- Pathology
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Question 67
Incorrect
-
A chef, whilst preparing food, cut her thumb with a knife. She transected the arteria princeps pollicis. This artery is a branch of the?
Your Answer: Superficial palmar arch
Correct Answer: Radial artery
Explanation:The radial artery branches into the arteria princeps pollicis as it turns medially into the deep part of the hand. The arteria princeps pollicis is distributed to the skin and subcutaneous tissue of the thumb.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 68
Correct
-
Regarding innervation to the peroneus brevis muscle:
Your Answer: Could be damaged by a fracture of the neck of the fibula
Explanation:The peroneus brevis is supplied by the fourth and fifth lumbar and first sacral nerves through the superficial peroneal nerve which is one of the two terminal branches of the common peroneal nerve. The common peroneal nerve winds around the neck of the fibula and can be injured in cases of fractured neck of fibula.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 69
Incorrect
-
The muscle that depresses the glenoid fossa directly is the:
Your Answer: Latissimus dorsi
Correct Answer: Pectoralis minor
Explanation:Situated at the upper part of the thorax beneath the pectoralis major, is a thin pectoralis minor, triangular muscle. It originates from the third, fourth and fifth ribs, near the cartilage and from the aponeurosis which covers the intercostals. These fibres move upwards and laterally to join and form a flat tendon. This is inserted into the medial border and upper surface of the coracoid process of the scapula. Through this medial anterior thoracic nerve, fibres from the pectoralis minor are received from the eighth cervical and first thoracic nerves. This pectoralis minor pushes down on the point of the shoulder (glenoid fossa), drawing the scapula downward and medially towards the thorax which throws the inferior angle backwards.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 70
Correct
-
A neurotransmitter of the nigrostriatal pathway is:
Your Answer: Dopamine
Explanation:Dopamine acts as a neurotransmitter in the brain, activating dopamine receptors. It is also a neurohormone released from the hypothalamus. It plays an important role in the reward system. It is believed that dopamine provides a teaching signal to parts of the brain responsible for acquiring new motor sequences (behaviours), by activation of dopamine neurons when an unexpected reward is presented. Loss of dopamine neurones in the nigrostriatal pathway causes Parkinson’s disease. In the frontal lobes, dopamine controls the flow of information from other areas of the brain, and thus, dopamine disorders in this region can cause a decline in neurocognitive functions, especially memory, attention and problem solving. Reduced dopamine concentrations in the prefrontal cortex are thought to contribute to attention-deficit disorder and some symptoms of schizophrenia. Dopamine is also the primary neuroendocrine regulator of the secretion of prolactin from the anterior pituitary gland. Dopamine is also commonly associated with the pleasure system of the brain. This plays a key role in understanding the mechanism of action of drugs (such as cocaine and the amphetamines), which seem to be directly or indirectly related to the increase of dopamine.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 71
Correct
-
A 45 -year-old female is recently diagnosed with breast cancer. She has a 8-cm-diameter mass in her left breast, with enlarged left axillary node. What is the most likely stage of her disease?
Your Answer: IIIA
Explanation:Stage IIIA breast cancer is T0–2 N2 M0 or T3 N1-2 M0 disease. It describes invasive breast cancer in which either: the tumour is smaller than 5 cm in diameter and has spread to 4 to 9 axillary lymph nodes; or it is found through imaging studies or clinical exam to have spread to internal mammary nodes (near the breastbone found during imaging tests or a physical exam); or the tumour is larger than 5 cm and has spread to 1 to 9 axillary nodes, or to internal mammary nodes. In this stage, the cancer has not metastasized (spread to distant sites).
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 72
Correct
-
Which of the following clinical signs will be demonstrated in a case of Brown-Séquard syndrome due to hemisection of the spinal cord at mid-thoracic level?
Your Answer: Ipsilateral spastic paralysis, ipsilateral loss of vibration and proprioception (position sense) and contralateral loss of pain and temperature sensation beginning one or two segments below the lesion
Explanation:Brown–Séquard syndrome results due to lateral hemisection of the spinal cord and results in a loss of motricity (paralysis and ataxia) and sensation. The hemisection of the cord results in a lesion of each of the three main neural systems: the principal upper motor neurone pathway of the corticospinal tract, one or both dorsal columns and the spinothalamic tract. As a result of the injury to these three main brain pathways the patient will present with three lesions. The corticospinal lesion produces spastic paralysis on the same side of the body (the loss of moderation by the upper motor neurons). The lesion to fasciculus gracilis or fasciculus cuneatus results in ipsilateral loss of vibration and proprioception (position sense). The loss of the spinothalamic tract leads to pain and temperature sensation being lost from the contralateral side beginning one or two segments below the lesion. At the lesion site, all sensory modalities are lost on the same side, and an ipsilateral flaccid paralysis.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 73
Correct
-
A 56-year-old woman complains of back pain, muscle spasms, weakness, and a burning sensation that radiates from her left hip to her toes. What's the most likely diagnosis?
Your Answer: Herniated nucleus pulposus
Explanation:A herniated disk will produce sensory disturbances, causing pain that radiates along the course of the sciatic nerve which is typically burning or stabbing, with or without back pain. The herniation is usually caused by age-related degeneration although trauma, injuries, or straining may also trigger it.
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 74
Incorrect
-
Purkinje fibres in the heart conduct action potentials at the rate of:
Your Answer: 0.2–1.1 m/s
Correct Answer: 1.5–4.0 m/s
Explanation:Purkinje fibres control the heart rate along with the sinoatrial node (SA node) and the atrioventricular node (AV node). The QRS complex is associated with the impulse passing through the Purkinje fibres. These fibres conduct action potential about six times faster than the velocity in normal cardiac muscle.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 75
Correct
-
A 7-year-old boys undergoes a testicular biopsy after a tumour is found in his right testis. Elements similar to hair and teeth are found in it. What kind of tumour is this?
Your Answer: Teratoma
Explanation:A teratoma is a tumour containing tissue elements that are similar to normal derivatives of more than one germ layer. They usually contain skin, hair, teeth and bone tissue and are more common in children, behaving as a benign tumour. After puberty, they are regarded as malignant and can metastasise.
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This question is part of the following fields:
- Pathology
- Urology
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Question 76
Correct
-
Which of the following is responsible for the maximum increase in total peripheral resistance on sympathetic stimulation?
Your Answer: Arterioles
Explanation:Arterioles are also known as the resistance vessels as they are responsible for approximately half the resistance of the entire systemic circulation. They are richly innervated by the autonomic nervous system and hence, will bring about the maximum increase in peripheral resistance on sympathetic stimulation.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 77
Correct
-
A 34-year-old woman has been suffering from headaches, fever, vomiting, and confusion for the last 5 days. A CT scan reveals an oedematous mass with ring enhancement in the left temporal region. It is biopsied, revealing glial cells, necrosis, neutrophils and lymphocytes. What is the most likely diagnosis?
Your Answer: Cerebral abscess
Explanation:A cerebral abscess can result from direct extension of cranial infections, penetrating head trauma, haematogenous spread, or for unknown causes. An abscess forms when an area of cerebral inflammation becomes necrotic and encapsulated by glial cells and fibroblasts. Oedema around the abscess can increase the intracranial pressure. Symptoms result from increased intracranial pressure and mass effects. It is most frequent in the third decade of life, and when it occurs in children, it is usually associated with congenital heart disease.
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This question is part of the following fields:
- Neurology
- Pathology
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Question 78
Correct
-
An abdominal aortogram of a 59 year-old female with an abdominal aortic aneurysm shows occlusion of the inferior mesenteric artery. The patient, however, does not complain of any symptoms. Occlusion of the inferior mesenteric artery is rarely symptomatic because its territory is supplied by branches of the:
Your Answer: Middle colic artery
Explanation:The transverse colon is supplied by the middle colic artery which is a branch from the superior mesenteric artery. If the inferior mesenteric artery was occluded, branches from the middle colic may go to the marginal artery which supplies the descending colon, sigmoid colon and rectum.. Ileocolic and right colic arteries also branch from the superior mesenteric artery that supply the colon but the middle colic, which serves the more distal part of the colon is the better answer. The gastroduodenal artery branches off the common hepatic artery, which supplies part of the duodenum, pancreas and stomach. The splenic artery supplies the spleen, pancreas and curvature of the stomach.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 79
Correct
-
Which of the following diseases is caused by intra-articular and/or extra-articular deposition of calcium pyrophosphate dihydrate (CPPD) crystals, due to unknown causes?
Your Answer: Pseudogout
Explanation:Pseudogout or chondrocalcinosis is a rheumatological disease caused by the accumulation of crystals of calcium pyrophosphate dihydrate (CPPD) in the connective tissues. It is frequently associated with other conditions, such as trauma, amyloidosis, gout, hyperparathyroidism and old age, which suggests that it is secondary to degenerative or metabolic changes in the tissues. The knee is the most commonly affected joint. It causes symptoms similar to those of rheumatoid arthritis or osteoarthritis.
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 80
Incorrect
-
A 26-year old man is brought to the A&E with a stab wound to the chest. The wound is in a part of the left lung that might partially fill the costomediastinal recess in full respiration. Where did the weapon strike this man?
Your Answer: Cupola
Correct Answer: Lingula
Explanation:During full inspiration, the lingual-of the left lung partially fills the costomediastinal recess. If the apex of the lung is fully filled with air, it would occupy the copula (the part of the pleura that extends above the first rib). The hilum is part of the lung where the neurovascular structures that form the root of the lung enter and leave the lung and doesn’t expand on inspiration. The middle lobe can expand to fill the costomediastinal recess, however, the middle lobe is on the right lung. The inferior lobe, during full inspiration, might fill the costodiaphragmatic recess.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 81
Incorrect
-
Which of the following is NOT true regarding malignant hyperpyrexia
Your Answer: It can be caused by suxamethonium
Correct Answer: It can be caused by nitrous oxide
Explanation:Malignant hyerpyrexia occurs in 1 in 150,000. All inhalational anaesthetic agents and suxamethonium, except nitrous oxide can cause malignant hyperpyrexia.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 82
Correct
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A 40-year old woman presents with tightening of the skin over her fingers which makes movement of her fingers difficult.. She also gives a history of her fingers turning blue on exposure to low temperatures. She admits to gradual weight loss. Investigations reveal negative rheumatoid factor, negative antinuclear antibody and a positive anticentromere body. Which of the following conditions is she likely to have?
Your Answer: Oesophageal stricture
Explanation:Scleroderma is a connective tissue disorder that ranges in severity and progression. The disease could show generalised skin thickening with rapid, fatal, visceral involvement; or only cutaneous involvement (typically fingers and face). The slow progressive form is also known as ‘limited cutaneous scleroderma’ or CREST syndrome (calcinosis cutis, Raynaud’s phenomenon, (o)oesophageal dysmotility, sclerodactyly, and telangiectasia).
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This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
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Question 83
Incorrect
-
Production of pain is most likely associated with:
Your Answer: Bradykinin
Correct Answer: Substance P
Explanation:Substance P is a short-chain polypeptide that functions as a neurotransmitter and as a neuromodulator, and is thus, a neuropeptide. It has been linked with pain regulation, mood disorders, stress, reinforcement, neurogenesis, respiratory rhythm, neurotoxicity, nausea and emesis. It is also a potent vasodilator as it brings about release of nitric oxide from the endothelium. Its release can also cause hypotension.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 84
Correct
-
Which of the following morphological characteristic is a salient feature of a pure apoptotic cell?
Your Answer: Chromatin condensation
Explanation:Apoptosis is the programmed death of cells which occurs as a normal and controlled part of an organism’s growth or development. The changes which occur in this process include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, chromosomal DNA fragmentation, and global mRNA decay. The cell membrane however remains intact and the dead cells are phagocytosed prior to any content leakage and thus inflammatory response.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 85
Incorrect
-
What is the innervation of the tensor tympani muscle?
Your Answer: Glossopharyngeal nerve
Correct Answer: Trigeminal nerve
Explanation:The tensor veli palatini is innervated by the medial pterygoid nerve, a branch of mandibular nerve, the third branch of the trigeminal nerve (CN V3) – the only muscle of the palate not innervated by the pharyngeal plexus, which is formed by the vagal and glossopharyngeal nerves.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 86
Incorrect
-
Extracellular body fluid as compared with intracellular body fluid:
Your Answer: Has greater volume
Correct Answer: Is relatively rich in glucose
Explanation:The percentages of body water contained in various fluid compartments add up to total body water (TBW). This water makes up a significant fraction of the human body, both by weight and by volume. Ensuring the right amount of body water is part of fluid balance, an aspect of homeostasis. The extracellular fluid (ECF) includes all fluids outside the cells. This fluid can be divided into three fluid departments: interstitial (in the tissue spaces) fluid, blood plasma and lymph, and specialised compartments called transcellular fluid. The extracellular fluid surrounds all the cells in the body and is in equilibrium with the intracellular fluid. So, its composition must remain fairly constant even though substances are passing into and out of the cells. The interstitial fluid, though called a fluid, is in a reality a gel-like composition made up of: water, proteoglycan molecules and collagen. The extracellular fluid constitutes 40% of total body water, with intracellular fluid making up the remaining 60%. It is relatively rich in glucose.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 87
Correct
-
Loperamide is a drug used to treat diarrhoea. What is the mechanism of action of loperamide?
Your Answer: Opiate agonist
Explanation:Loperamide is an opioid-receptor agonist and acts on the mu opioid receptors in the myenteric plexus of large intestine. It works by decreasing the motility of the circular and longitudinal smooth muscles of the intestinal wall. It is often used for this purpose in gastroenteritis, inflammatory bowel disease, and short bowel syndrome.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 88
Correct
-
What class of drugs does buspirone belong to?
Your Answer: Anxiolytic
Explanation:Buspirone is an anxiolytic agent and a serotonin-receptor agonist that belongs to the azaspirodecanedione class of compounds. It shows no potential for addiction compared with other drugs commonly prescribed for anxiety, especially the benzodiazepines. The development of tolerance has not been noted. It is primarily used to treat generalized anxiety disorders. It is also commonly used to augment antidepressants in the treatment of major depressive disorder.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 89
Incorrect
-
Which of the following will be affected by a lesion in the posterior column-medial lemniscus system?
Your Answer: Hearing
Correct Answer: Fine touch
Explanation:The posterior column–medial lemniscus (PCML) pathway is a sensory pathway that transmits fine touch and conscious proprioceptive information from the body to the brain. As the posterior columns are also known as dorsal columns, the pathway is also called the dorsal column–medial lemniscus system or DCML.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 90
Incorrect
-
A 46-year old female patient experienced a stroke that affected her glossopharyngeal nerve. Damage to the glossopharyngeal nerve would most likely:
Your Answer: Affect the parasympathetic innervation to the submandibular gland
Correct Answer: Result in general sensory deficit to the pharynx
Explanation:The glossopharyngeal nerve (CN IX) has many functions which include:
– Contributes to the pharyngeal plexus
– Receiving general somatic sensory fibres from the tonsils, pharynx, the middle ear and the posterior third of the tongue.
– supplies motor fibres to only one muscle; the stylopharyngeus muscle.
– provides parasympathetic fibres to the parotid gland via the otic ganglion.
– Receives visceral sensory fibres from the carotid bodies & carotid sinus.
– Receives special visceral sensory fibres from the posterior third of the tongue.
The above functions will directly be affected by the damage of the glossopharyngeal nerve.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 91
Incorrect
-
A 55-year-old male chronic smoker is diagnosed with non-small-cell cancer. His right lung underwent complete atelectasis and he has a 7cm tumour involving the chest wall. What is the stage of the lung cancer of this patient?
Your Answer: T2
Correct Answer: T3
Explanation:Non-small-cell lung cancer is staged through TNM classification. The stage of this patient is T3 because based on the TNM classification the tumour is staged T3 if > 7 cm or one that directly invades any of the following: Chest wall (including superior sulcus tumours), diaphragm, phrenic nerve, mediastinal pleura, or parietal pericardium; or the tumour is in the main bronchus < 2 cm distal to the carina but without involvement of the carina, Or it is associated with atelectasis/obstructive pneumonitis of the entire lung or separate tumour nodule(s) in the same lobe.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 92
Correct
-
Lack of findings in the bladder but presence of atypical epithelial cells in urinalysis is most often associated with which of the following conditions?
Your Answer: Transitional cell carcinoma of renal pelvis
Explanation:The presence of atypical cells in urinalysis without findings in the bladder suggests a lesion located higher up, most probably in ureters or renal pelvis. Transitional cell cancer of the renal pelvis is a disease in which malignant cells form in the renal pelvis and is characterised by the presence of abnormal cells in urine cytology.
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This question is part of the following fields:
- Pathology
- Renal
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Question 93
Incorrect
-
Which statement is true about the inferior sagittal sinus?
Your Answer: Is found in the falx cerebelli
Correct Answer: Is formed between two layers of meningeal dura
Explanation:The inferior sagittal sinus is also known as the inferior longitudinal sinus. It courses along the inferior border of the falx cerebri, superior to the corpus callosum. It is cylindrical in shape and increases in size as it passes backward ending in the straight sinus. It receives blood from the deep and medial aspects of the cerebral hemispheres and drains into the straight sinus.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 94
Correct
-
Elevated mean corpuscular volume with hypersegmented neutrophils and low reticulocyte index is seen in on the blood count of a middle-aged lady about to undergo elective surgery. On enquiry, she mentions feeling tired for a few months. Which of the following investigations should be carried out in her to reach a diagnosis?
Your Answer: Serum vitamin B12 and folate
Explanation:Elevated levels of MCV indicates megaloblastic anaemia, which are associated with hypersegmented neutrophils. Likely causes include vitamin B12 or folate deficiency. Megaloblastic anaemia results from defective synthesis of DNA. As RNA production continues, the cells enlarge with a large nucleus. The cytoplasmic maturity becomes greater than nuclear maturity. Megaloblasts are produced initially in the marrow, before blood. Dyspoiesis makes erythropoiesis ineffective, causing direct hyperbilirubinemia and hyperuricemia. As all cell lines are affected, reticulocytopenia, thrombocytopenia and leukopenia develop. Large, oval blood cells (macro-ovalocytes) are released in the circulation, along with presence of hypersegmented neutrophils.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 95
Correct
-
In a cardiac cycle, what event does the closing of atrioventricular (AV) valves coincide with?
Your Answer: First heart sound
Explanation:In the cardiac cycle, the closing of the atrioventricular (AV) valves coincides with the onset of ventricular systole. This event marks the beginning of the isovolumetric contraction phase, where the ventricles begin to contract, but the volume of blood in the ventricles remains the same because both the AV valves and the semilunar valves (aortic and pulmonary valves) are closed. The closing of the AV valves produces the first heart sound, known as “S1” or “lub.”
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 96
Correct
-
The tympanic membrane is a thin semi-transparent membrane that separates the tympanic cavity from the bottom of the external acoustic meatus. The interior of the tympanic membrane is innervated by which of the following cranial nerves?
Your Answer: Glossopharyngeal
Explanation:The glossopharyngeal nerve, known as the ninth cranial nerve (CN IX), is a mixed nerve that carries afferent sensory and efferent motor information. The glossopharyngeal nerve has five distinct general functions:
– The branchial motor (special visceral efferent), supplies the stylopharyngeus muscle.
– The visceral motor (general visceral efferent), provides parasympathetic innervation of the parotid gland via the otic ganglion.
– The visceral sensory (general visceral afferent), carries visceral sensory information from the carotid sinus and carotid body.
– The general sensory (general somatic afferent), provides general sensory information from the inner surface of the tympanic membrane, upper pharynx (GVA), and the posterior one-third of the tongue.
– The visceral afferent (special visceral afferent), provides taste sensation from the posterior one-third of the tongue, including the circumvallate papillae.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 97
Correct
-
A 42 year old man with an abdominal aortic aneurysm (AAA) underwent an abdominal aortic angiography which revealed that his inferior mesenteric artery was occluded. If this patient showed no symptoms, the most likely reason is that the area the inferior mesenteric artery supplies, must be supplied by collateral blood flow from which arteries?
Your Answer: Left and middle colic
Explanation:The arterial branches that form an anastomosis between the superior mesenteric artery and the inferior mesenteric artery are the left colic artery and the middle colic artery. The middle colic artery is the most distal branch of the superior mesenteric artery while the left colic forms the most proximal branch of the inferior mesenteric artery. These two arteries will give collateral blood flow in the case that the inferior mesenteric artery gets occluded. The superior mesenteric artery gives off the following branches; ileocolic, appendicular, ileal artery, right colic and middle colic arteries. The left colic, sigmoid and superior rectal arteries are branches of the inferior mesenteric artery. The marginal artery branches off directly from the abdominal aorta.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 98
Correct
-
A 72 year old man suffered a MI. What is the approximate time needed by the scar tissue of the MI to recover and attain full strength?
Your Answer: Several months
Explanation:A week following a MI attack, a little collagen starts to form and deposit. By the end of the 2nd week, neovascularisation of the scar occurs, with some collagen being laid down in a haphazard fashion. By this time the scar attains some strength. During the next 6 months, collagen is constantly being laid down and is rearranged in order to shrink the scar. Most of the blood vessels by this time have regenerated, decreasing vascularity of the scar reaching full maturity.
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This question is part of the following fields:
- Cell Injury & Wound Healing; Cardiovascular
- Pathology
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Question 99
Correct
-
Which of these laboratory findings will indicate a fetal neural tube defect when done between 15 and 20 weeks of pregnancy?
Your Answer: Increased alpha-fetoprotein
Explanation:Maternal serum screening during the second trimester is a non-invasive way of identifying women at increased risk of having children with a neural tube defect and should be offered to all pregnant women. The results are most accurate when the sample is taken between 15 and 20 weeks of gestation. Elevated levels of alpha-fetoprotein suggest open spina bifida, anencephaly, risk of pregnancy complications, or multiple pregnancy.
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This question is part of the following fields:
- Neurology
- Pathology
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Question 100
Incorrect
-
There are several mechanisms involved in the transport of sodium ions from blood to interstitial fluid of the muscle cells. Which of the following mechanisms best describes this phenomenon?
Your Answer: Active transport through endothelial cell membranes
Correct Answer: Diffusion through channels between endothelial cells
Explanation:Capillaries are the smallest of the body’s blood vessels, measuring 5–10 μm and they help to enable the exchange of water, oxygen, carbon dioxide, and many other nutrients and waste substances between the blood and the tissues surrounding them. The walls of capillaries are composed of only a single layer of cells, the endothelium. Ion channels are pore-forming proteins that help to establish and control the small voltage gradient that exists across the plasma membrane of all living cells by allowing the flow of ions down their electrochemical gradient. An ion channel is an integral membrane protein or more typically an assembly of several proteins. The archetypal channel pore is just one or two atoms wide at its narrowest point. It conducts a specific ion such as sodium or potassium and conveys them through the membrane in single file.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 101
Correct
-
A 45-year old male patient with a long history of alcoholism developed liver cirrhosis that has led to portal hypertension. Which of the following plexuses of veins is most likely dilated in this patient?
Your Answer: Haemorrhoidal plexus
Explanation:The haemorrhoidal plexus or also known as the rectal plexus is a venous plexus that surrounds the rectum. This venous plexus in males communicates anteriorly with the vesical plexus and uterovaginal plexus in females. This venous plexus forms a site of free communication between the portal and systemic venous systems. In the case of portal hypertension this plexus would most likely dilate due to the increased pressure.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 102
Incorrect
-
Most of the coagulation factors are serine proteases. Which of the following is not one of them?
Your Answer: Factor XII
Correct Answer: Factor XIII
Explanation:Serine protease coagulation factors include: thrombin, plasmin, Factors X, XI and XII. Factor VIII and factor V are glycoproteins and factor XIII is a transglutaminase.
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This question is part of the following fields:
- General
- Physiology
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Question 103
Correct
-
In the adult heart, the sinus venosus gives rise to the:
Your Answer: Coronary sinus
Explanation:The sinus venosus is a large quadrangular cavity which precedes the atrium on the venous side of the chordate heart. It exists distinctly only in the embryonic heart (where it is found between the two venae cavae); however, the sinus venosus persists in the adult. In the adult, it is incorporated into the wall of the right atrium to form a smooth part called the sinus venarum, which is separated from the rest of the atrium by a ridge of fibres called the crista terminalis. The sinus venosus also forms the SA node and the coronary sinus.
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This question is part of the following fields:
- Anatomy
- Embryology
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Question 104
Correct
-
A 56-year old male with history of previous abdominal surgery presents to the emergency department with severe abdominal pain that is increasing in intensity. This pain is associated with abdominal distension and faint, high-pitched bowel sounds. An old scar is also noted on the abdomen. An erect abdominal X-ray shows multiple air-fluid levels in dilated bowel loops. No occult blood was found in stool sample. What is the most likely predisposing factor for his present condition?
Your Answer: Adhesions from previous surgery
Explanation:The described features suggest acute bowel obstruction. The scar described points toward previous surgery, which suggests development of peritoneal adhesions that could lead to obstruction. Hepatitis does not lead to dilated bowel loops. Amoebiasis could lead to inflammatory bowel disease, however, occult blood in stool is usually positive. Ileal adenocarcinoma is rare. Meckel’s diverticulum can possibly lea to obstruction but the findings described here are more consistent with obstruction due to peritoneal adhesions from a past surgery.
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This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
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Question 105
Correct
-
A suspected recreational drug user was brought to the Emergency department in an unconscious state, and was found to be hypoventilating. Which of the following set of arterial blood gas analysis report is most consistent with hypoventilation as the primary cause? pH, pa(CO2) (mmHg), pa(O2) (mmHg).
Your Answer: 7.28, 55, 81
Explanation:Hypoventilation (or respiratory depression) causes an increase in carbon dioxide (hypercapnia) and respiratory acidosis. It can result due to drugs such as alcohol, benzodiazepines, barbiturates, opiates, mechanical conditions or holding ones breath. Strong opioids such as heroin and fentanyl are commonly implicated and can lead to respiratory arrest. In recreational drug overdose, acute respiratory acidosis occurs with an increase in p(CO2) over 45 mm Hg and acidaemia (pH < 7.35)
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 106
Correct
-
A 32-year old gentleman came to the emergency department, complaining of progressively increasing weakness in his arms and legs over 5 days. On examination, there is symmetrical weakness on both sides of his face, along with weakness of the proximal and distal muscles of all four limbs. No loss of sensation noted. Deep tendon reflexes could not be elicited and plantar responses were downward. On enquiry, it was revealed that he had an upper respiratory tract infection 10 days ago. The likely diagnosis is:
Your Answer: Guillain–Barré syndrome
Explanation:Guillain–Barré syndrome (GBS) is an acute, autoimmune polyradiculoneuropathy which affects the peripheral nervous system and is usually triggered by an acute infectious process. 75% patients have a history of acute infection within the past 1–4 weeks, usually respiratory or gastrointestinal. immunisations have also been implicated. The most common form is acute inflammatory demyelinating polyneuropathy. It results in an ascending paralysis with complete loss of deep tendon reflexes. Treatment includes immunoglobulins and supportive care. However, the disease may be fatal due to severe pulmonary complications and dysautonomia.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 107
Correct
-
A patient with testicular seminoma has the following tumour markers: LDH 1.3 times the reference levels, β-hCG 4500 mIU/ml and AFP 875 ng/ml. What's the serum tumour marker stage in this case?
Your Answer: S1
Explanation:According to AJCC guidelines, the serum tumour marker staging is the following:
S0: marker studies within normal limits
S1: lactate dehydrogenase (LDH) less than 1.5 times the reference range, beta-human chorionic gonadotrophin (β-hCG) <5000 mIU/ml, and alpha-fetoprotein (AFP) <1000 ng/ml S2: LDH 1.5–10 times the reference range, β-hCG 5000–50,000 mIU/ml or AFP 1000–10,000 ng/ml S3: LDH greater than 10 times the reference range, β-hCG >50,000 mIU/ml or AFP >10,000 ng/ml.
According to this, the patient’s tumour belongs to the S1 stage.
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This question is part of the following fields:
- Pathology
- Urology
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Question 108
Correct
-
A patient who complained of pain on the lower left side of the back had an x-ray done which confirmed a hernia passing posterolaterally, just superior to the iliac crest. Where is this hernia passing through?
Your Answer: Lumbar triangle
Explanation:The lumber triangle is bound medially by the border of the latissimus dorsi, laterally by the external abdominal oblique and by the iliac crest inferiorly. This is exactly where the hernia that is described is located.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 109
Correct
-
A construction worker is brought to the A&E after a fall on site. The patient is conscious but complains of inability to feel his legs. A neurological examination reveals that he has no cutaneous sensation from his umbilicus to his toes. What is the likely level of the spinal cord that is injured?
Your Answer: T10
Explanation:The umbilicus has a relatively consistent position in humans and thus serves as an important land mark. The skin around the waist at the level of the umbilicus is supplied by the tenth thoracic spinal nerve (T10 dermatome).
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 110
Correct
-
A 13 year old girl presented with signs of shortness of breath, chest pain, non-productive cough, oedema of the lower extremities and cyanosis of the fingertips. She has a history of a ventricular septal defect not surgically corrected. The most probable cause of these symptoms is:
Your Answer: Shunt reversal
Explanation:A ventricular septal defect (VSD) is a common form of congenital heart defects and is characterised by the presence of a hole in the wall that separates the right from the left ventricle. Medium or large defects can cause many complications. One of these complication is Eisenmenger syndrome, characterised by reversal of the shunt (from left-to-right shunt into a right-to-left) ,cyanosis and pulmonary hypertension.
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This question is part of the following fields:
- Cardiovascular
- Pathology
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Question 111
Incorrect
-
A 20-year old cyclist falls off a speeding bike and fractures a structure that articulates with the tubercle of the 7th rib. Which structure is fractured?
Your Answer: Body of vertebra T7
Correct Answer: Transverse process of vertebra T7
Explanation:A rib tubercle is a projection that is postero-inferior and lateral to the neck of a rib which articulates with the transverse process of the corresponding vertebra i.e. of the same number. Therefore, the tubercle of rib 7 articulates with the transverse process of T7 vertebra. The head of the rib 7, on the other hand, articulates with the 6th vertebra superiorly and the 7th vertebra inferiorly.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 112
Correct
-
An experiment is carried out to observe engulfment and phagocytosis of microbes. Strep pneumoniae are added to a solution of leukocytes with a substance added to enhance the process of phagocytosis. What is this substance?
Your Answer: Complement C3b
Explanation:C3b is cleaved from C3 complement with the help of the enzyme C3- convertase. It binds to the cell surface of the offending substance and opsonizes it. This makes it easy for the phagocytes to detect and eliminate them.
IgM does not act as an opsonin but igG does.
Selectins aid leukocytes to bind to the endothelial surfaces.
C5a is a chemo-attractant and histamine a vasodilator.
NADPH oxidises offending substance after phagocytosis within the macrophage.
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This question is part of the following fields:
- Inflammation & Immunology
- Pathology
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Question 113
Correct
-
When a patient is standing erect, pleural fluid would tend to accumulate in which part of the pleural space?
Your Answer: Costodiaphragmatic recess
Explanation:The costo-diaphragmatic recess is the lowest extent of the pleural cavity or sac. Any fluid in the pleura will by gravity accumulate here when a patient is standing erect.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 114
Incorrect
-
A 35 year-old female developed food poisoning 24H after eating canned food. She complained of abdominal cramps, with nausea and vomiting. Shortly after she suddenly developed weakness, blurring of vision, difficulty in swallowing and breathing. Which of the following organisms is most likely associated with fatal food poisoning?
Your Answer: Vibrio cholerae
Correct Answer: Clostridium botulinum
Explanation:C. botulinum is a Gram-positive, rod-shaped, spore-forming bacterium. It is an obligate anaerobe, meaning that oxygen is poisonous to the cells. Only botulinum toxin types A, B, E, and F cause disease in humans. Types A, B, and E are associated with foodborne illness. Botulism poisoning can occur due to preserved or home-canned, low-acid food that was not processed using correct preservation times and/or pressure. Signs and symptoms of foodborne botulism typically begin between 18 and 36 hours after the toxin gets into the body, but can range from a few hours to several days, depending on the amount of toxin ingested. Botulinum that is produced by Clostridium botulinum can cause respiratory and muscular paralysis.
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 115
Correct
-
A 38-year-old woman with end-stage renal disease, is undergoing haemodialysis. She has normocytic normochromic anaemia. What is the best treatment for her?
Your Answer: Erythropoietin
Explanation:E erythropoietin (EPO) is a hormone that is released by the kidney. It is responsible for the regulation of red blood cell production in the body. It can be made using recombinant technology and is used in the treatment of anaemia of chronic renal failure and in patients under going chemotherapy
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This question is part of the following fields:
- General
- Physiology
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Question 116
Correct
-
A 4-year-old child was brought to a paediatrician for consult due to a palpable mass in his abdomen. The child has poor appetite and regularly complains of abdominal pain. The child was worked up and diagnosed with a tumour. What is the most likely diagnosis ?
Your Answer: Nephroblastoma
Explanation:Nephroblastoma is also known as Wilms’ tumour. It is a cancer of the kidneys that typically occurs in children. The median age of diagnose is approximately 3.5 years. With the current treatment, approximately 80-90% of children with Wilms’ tumour survive.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 117
Incorrect
-
A 18-year old girl presents to her doctor with an excessively enlarged left breast as compared to the right breast since puberty. The most likely cause for this is:
Your Answer: Cystosarcoma phyllodes
Correct Answer: Virginal breast hypertrophy
Explanation:Virginal breast hypertrophy’ is the term assigned to excessive growth of breasts during puberty and is a common phenomenon. It is also known as ‘juvenile macromastia’ or ‘ juvenile gigantomastia’. The breast hypertrophy often starts with menarche and occasionally occurs in growth spurts. These spurts can cause physical discomfort, red and itchy skin or pain in the breasts. The breasts can also grow continuously over several years and lead to overdevelopment of a normal breast. Nipples also undergo enlargement along with the breasts.
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This question is part of the following fields:
- Pathology
- Women's Health
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Question 118
Correct
-
A 45-year-old woman was brought to the emergency department due to fever and chills. She has a history of recurrent UTI and complains of dysuria and urinary frequency. Urinary white blood cell count is >200 cell/high power field. If urine culture is performed, what is the most likely organism that will grow?
Your Answer: Escherichia coli
Explanation:The pathogen that most likely causes recurrent urinary tract infection in young women are E. coli, Enterococcus and Staphylococcus saprophyticus.
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 119
Correct
-
Passing through the lesser sciatic foramen are the:
Your Answer: Pudendal nerve
Explanation:Structures that pass through the lesser sciatic foramen include:
– the pudendal nerve
– the nerve to obturator internus
– internal pudendal artery
– the tendon of obturator internus
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 120
Correct
-
A histology report of a cervical biopsy taken from a patient with tuberculosis revealed the presence of epithelioid cells. What are these cells formed from?
Your Answer: Macrophages
Explanation:Granulomas formed in tuberculosis are called tubercles and are made up polynuclear phagocytes, Langhans cells and epithelioid cells. Macrophages when enlarged, consist of abundant cytoplasm and have a tendency of arranging themselves very closely to each other representing epithelial cells. These enlarged macrophages are therefore termed as epithelioid cells.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 121
Incorrect
-
The ostium of the maxillary sinus opens into which of the following structures?
Your Answer: Inferior meatus
Correct Answer: Middle meatus
Explanation:The maxillary sinuses usually develop symmetrically. The maxillary sinus ostium drains into the infundibulum which joins the hiatus semilunaris and drains into the middle meatus.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 122
Incorrect
-
A tumour on the floor of the fourth ventricle is most likely to compress which of the following cranial nerve nuclei?
Your Answer: Oculomotor
Correct Answer: Abducent
Explanation:The fourth ventricle, is a cavity of the brains ventricular system in which the cerebrospinal fluid is formed. This cavity is located behind the pons and upper half of the medulla oblongata. It extends from the cerebral aqueduct, to its connection to the third ventricle, and to the obex- which is the caudal tip of the fourth ventricle. The floor of the fourth ventricle consists of three parts – superior, intermediate and inferior. This inferior aspect of the floor of the fourth ventricle has the nucleus of the abducens nerve, CN VI which is looped over by the facial nerve.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 123
Incorrect
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Which of the following will be a seen in a patient with a plasma thyroid-stimulating hormone (TSH) level of 14 mU/l (normal < 5 mU/l) and a low T3 resin uptake of 19% (normal 25–35%)?
Your Answer: Tachycardia
Correct Answer: Periorbital swelling and lethargy
Explanation:Low T3 resin uptake combined with raised TSH is indicative of hypothyroidism. Signs and symptoms include dull expression, facial puffiness, lethargy, periorbital swelling due to infiltration with mucopolysaccharides, bradycardia and cold intolerance. Anxiety, palpitations, tachycardia, raised body temperature, heat intolerance and weight loss are all seen in hyperthyroidism.
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This question is part of the following fields:
- Endocrinology
- Physiology
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Question 124
Correct
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A young girl who presented with a clinical picture of type I hypersensitivity reaction with eosinophilia is most likely to have?
Your Answer: Liver flukes
Explanation:Usually a parasitic infection will be associated with a type I hypersensitivity reaction.
Amyloid deposition will not cause an immune reaction.
Organic dust will lead to a type III hypersensitivity reaction.
Cell mediated as well as humoral immune mechanism play a part in syphilis, but they are do not specifically cause a type I reaction.
Malaria is cause by plasmodium and is not cause of a hypersensitivity reaction.
Atopic dermatitis will not be accompanied by eosinophilia.
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This question is part of the following fields:
- Inflammation & Immunology
- Pathology
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Question 125
Incorrect
-
During thyroidectomy, the recurrent laryngeal nerves are vulnerable to injury. Which of the following muscles will not be affected in cases where the recurrent laryngeal nerve is severed?
Your Answer: Oblique arytenoid
Correct Answer: Cricothyroid
Explanation:All muscles of the larynx are supplied by the recurrent laryngeal nerve except for the cricothyroid which is supplied by the vagus nerve.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 126
Correct
-
Atrial septal defect (ASD) is most likely to be due to incomplete closure of which one of the following structures:
Your Answer: Foramen ovale
Explanation:Atrial septal defect is a congenital heart defect that results in a communication between the right and left atria of the heart and may involve the interatrial septum. It results from incomplete closure of the foramen ovale which is normally open during fetal life and closes just after birth.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 127
Correct
-
A 34-year-old woman with pelvic inflammatory disease is administered ceftriaxone. The subclass of antibiotics that ceftriaxone belongs to is:
Your Answer: Third-generation cephalosporins
Explanation:Ceftriaxone is a third-generation cephalosporin antibiotic. It has a broad spectrum of activity against Gram-positive and Gram-negative bacteria. Its indications include middle ear infections, endocarditis, meningitis, pneumonia, bone and joint infections, intra-abdominal infections, skin infections, urinary tract infections, gonorrhoea, and pelvic inflammatory disease.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 128
Correct
-
Cervical intraepithelial neoplasia on Pap smear of a 34-year old lady is most likely associated with which of the following?
Your Answer: Human papillomavirus infection
Explanation:CIN (Cervical intraepithelial neoplasia) is considered a precursor of cervical cancer and is likely caused due to infection with human papillomavirus (HPV) types 16, 18, 31, 33, 35 or 39. The risk factors for cervical cancer include multiple sex partners, young age at the time of first intercourse, intercourse with men whose previous partners had cervical cancer. Also, smoking and immunodeficient states are considered contributory. CIN is graded as mild (grade I), moderate (grade II) and severe dysplasia or carcinoma in situ (grade III). CIN III rarely regresses spontaneously and can lead to invasive carcinoma by invading the basement membrane. Squamous cell carcinomas are the commonest cervical cancer seen in 80-85% of all cases. Others are commonly adenocarcinomas. Cervical cancer can spread by direct extension, lymphatic spread to pelvic and para-aortic nodes or by hematogenous route.
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This question is part of the following fields:
- Pathology
- Women's Health
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Question 129
Correct
-
The optic foramen, superior orbital fissure, foramen ovale, foramen rotundum and foramen sinosum are all located on which bone at the base of the skull?
Your Answer: Sphenoid
Explanation:The sphenoid bone consists of two parts, a central part and two wing-like structures that extend sideways towards each side of the skull. It forms the base of the skull, and floor and sides of the orbit. On its central part lies the optic foramen. The foramen ovale, foramen spinosum and foramen rotundum lie on its great wing while the superior orbital fissure lies on its lesser wing.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 130
Incorrect
-
If a catheter is placed in the main pulmonary artery of a healthy 30-year-old woman, which of the following will be its mean pulmonary arterial pressure?
Your Answer: 5 mmHg
Correct Answer: 15 mmHg
Explanation:The pulmonary artery pressure (PA pressure) is a measure of the blood pressure found in the main pulmonary artery. The hydrostatic pressure of the pulmonary circulation refers to the actual pressure inside pulmonary vessels relative to atmospheric pressure. Hydrostatic (blood pressure) in the pulmonary vascular bed is low compared with that of similar systemic vessels. The mean pulmonary arterial pressure is about 15 mmHg (ranging from about 13 to 19 mmHg) and is much lower than the average systemic arterial pressure of 90 mmHg.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 131
Correct
-
In the glomerulus of the kidney, the mesangium is a structure associated with the capillaries. It has extraglomerular mesangial cells that:
Your Answer: Form the juxtaglomerular apparatus in combination with the macula densa and juxtaglomerular cells
Explanation:The mesangium is an inner layer of the glomerulus, within the basement membrane surrounding the glomerular capillaries. The mesangial cells are phagocytic and secrete the amorphous basement membrane-like material known as the mesangial matrix. They are typically separated from the lumen of the capillaries by endothelial cells. The other type of cells in the mesangium are the extraglomerular mesangial cells which form the juxtaglomerular apparatus in combination with two other types of cells: the macula densa of the distal convoluted tubule and juxtaglomerular cells of the afferent arteriole. This apparatus controls blood pressure through the renin–angiotensin–aldosterone system.
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This question is part of the following fields:
- Physiology
- Renal
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Question 132
Correct
-
A growing tumour is impinging on the lingual artery in the floor of the mouth. Which structure will experience decreased blood flow?
Your Answer: The sublingual gland
Explanation:The paired sublingual glands are major salivary glands in the mouth. They are the smallest, most diffuse, and the only unencapsulated major salivary glands. They provide only 3-5% of the total salivary volume. The gland receives its blood supply from the sublingual and submental arteries. The sublingual artery is a branch of the lingual artery, thus damage to the lingual artery will decrease the blood flow to the sublingual gland.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 133
Correct
-
A 54-year-old woman is re-admitted to the hospital with shortness of breath and sharp chest pain 2 weeks after surgical cholecystectomy. The most probable cause of these clinical findings is:
Your Answer: Pulmonary embolus
Explanation:Pulmonary embolism is caused by the sudden blockage of a major lung blood vessel, usually by a blood clot. Symptoms include sudden sharp chest pain, cough, dyspnoea, palpitations, tachycardia or loss of consciousness. Risk factors for developing pulmonary embolism include long periods of inactivity, recent surgery, trauma, pregnancy, oral contraceptives, oestrogen replacement, malignancies and venous stasis.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 134
Incorrect
-
A 30-year-old man is brought to the emergency department suffering from extreme dehydration, and subsequent hypotension and tachycardia. Which part of the kidney will compensate for this loss?
Your Answer: Proximal convoluted tubule
Correct Answer: Collecting ducts
Explanation:The collecting duct system of the kidney consists of a series of tubules and ducts that physically connect nephrons to a minor calyx or directly to the renal pelvis. The collecting duct system is the last component of the kidney to influence the body’s electrolyte and fluid balance. In humans, the system accounts for 4–5% of the kidney’s reabsorption of sodium and 5% of the kidney’s reabsorption of water. At times of extreme dehydration, over 24% of the filtered water may be reabsorbed in the collecting duct system.
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This question is part of the following fields:
- Physiology
- Renal
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Question 135
Incorrect
-
C5a (a complement component) is a potent?
Your Answer: Cytokine
Correct Answer: Anaphylotoxin
Explanation:C5a is a strong chemoattractant as well as an anaphylotoxin and is involved in the recruitment of inflammatory cells such as neutrophils, eosinophils, monocytes, and T lymphocytes. It is also involved in activation of phagocytic cells, release of granule-based enzymes and generation of oxidants. All of which contribute to innate immune functions.
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This question is part of the following fields:
- General
- Physiology
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Question 136
Correct
-
A 47 -year-old male was admitted due to a bleeding peptic ulcer. On his 3rd hospital day, he developed a cardiac arrhythmia. His serum potassium was markedly elevated. What is the most likely cause of hyperkalaemia in this patient?
Your Answer: Multiple blood transfusions
Explanation:Patients with gastrointestinal bleeding often require blood transfusion. Among the various side effects of blood transfusions, is the increase of potassium levels. The use of stored blood for transfusions is followed by an increase of serum potassium levels. Potassium level increases are more pronounced in patients who receive blood stored for more than 12 d. Furthermore, the lysis and destruction of red blood cells, especially in the transfusion of older PRBCs, can further increase potassium levels. Excessive use of a PPi has been associated with hyperkaelemia however would be less likely in this acute setting.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
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Question 137
Incorrect
-
Calculate the resistance of the artery if the pressure at one end is 60 mmHg, pressure at the other end is 20 mm Hg and the flow rate in the artery is 200 ml/min.
Your Answer: 0.5
Correct Answer: 0.2
Explanation:Flow in any vessel = Effective perfusion pressure divided by resistance, where effective perfusion pressure is the mean intraluminal pressure at the arterial end minus the mean pressure at the venous end. Thus, in the given problem, resistance = (60 − 20)/200 = 0.2 mmHg/ml per min.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 138
Correct
-
A week after a renal transplant the patient received antilymphocyte globulins. Shortly after she developed fever and hypotension. Which of the following mechanisms is involved in this response?
Your Answer: Type III hypersensitivity
Explanation:Type III hypersensitivity is characterized by soluble immune complexes which are aggregations of IgG and IgM antibodies with antigens that deposit in different tissues e.g. the skin, joints, kidneys. They can then trigger an immune response by activating the complement cascade. This reaction can take hours to develop and examples include: immuno-complex glomerulonephritis, rheumatoid arthritis, SLE, subacute bacterial endocarditis, arthus reaction and serum sickness.
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This question is part of the following fields:
- Inflammation & Immunology
- Pathology
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Question 139
Correct
-
Glucose is the most important source of energy for cellular respiration. The transport of glucose in the renal tubular cells occurs via:
Your Answer: Secondary active transport with sodium
Explanation:In 1960, Robert K. Crane presented for the first time his discovery of the sodium-glucose cotransport as the mechanism for glucose absorption. Glucose transport through biological membranes requires specific transport proteins. Transport of glucose through the apical membrane of renal tubular as well as intestinal epithelial cells depends on the presence of secondary active Na+–glucose symporters, SGLT-1 and SGLT-2, which concentrate glucose inside the cells, using the energy provided by co-transport of Na+ ions down their electrochemical gradient.
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This question is part of the following fields:
- Physiology
- Renal
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Question 140
Correct
-
The most important difference between interstitial fluid and plasma is the:
Your Answer: Protein concentration
Explanation:Interstitial fluid (or tissue fluid or intercellular fluid) is a solution that surrounds the cells of multicellular animals. It is the main component of the extracellular fluid, which also includes plasma, lymph and transcellular fluid. Plasma, the major component in blood, communicates freely with interstitial fluid through pores and intercellular clefts in capillary endothelium. Interstitial fluid consists of a water solvent containing amino acids, sugars, fatty acids, coenzymes, hormones, neurotransmitters, salts, as well as waste products from the cells. Red blood cells, platelets and plasma proteins cannot pass through the walls of the capillaries. The resulting mixture that does pass through is essentially blood plasma without the plasma proteins. Tissue fluid also contains certain types of white blood cells. Once the extracellular fluid collects into small vessels it is considered to be lymph, and the vessels that carry it back to the blood are called the lymphatic vessels. The lymphatic system returns protein and excess interstitial fluid to the circulation.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 141
Correct
-
A 24-year old, lactating mother presents to the clinic with a tender, 1.5cm mass just below the right nipple, which shows multiple fissures. What finding is likely associated with her condition?
Your Answer: Staphylococcus aureus infection
Explanation:Breast abscess occur commonly in lactating mothers in the postpartum period due to cracking of the nipple. It is commonly caused due to Staphylococcus aureus infection. Fat necrosis usually results from trauma wherein an ill-defined mass is formed. Ductal carcinomas are malignant masses which are not tender usually, and rare in the young age group. Plasma cell mastitis affect women in an older age group. Sclerosing adenosis is a type of fibrocystic disease which can lead to a tender, cystic mass but no fissuring or cracks are seen in the nipple. Fibroadenoma and lipomas are non-tender, well-defined masses.
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This question is part of the following fields:
- Pathology
- Women's Health
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Question 142
Incorrect
-
What is the 5 year survival rate of a patient who is diagnosed with stage III colon cancer, who underwent successful resection and completed the prescribed session of adjuvant chemotherapy?
Your Answer: 20-30%
Correct Answer: 30%–60%
Explanation:In this patient who has stage III colon cancer, the survival rate is 30-60%. For stage I or Dukes’ stage A disease, the 5-year survival rate after surgical resection exceeds 90%. For stage II or Dukes’ stage B disease, the 5-year survival rate is 70%–85% after resection, with or without adjuvant therapy. For stage III or Dukes’ stage C disease, the 5-year survival rate is 30%– 60% after resection and adjuvant chemotherapy and for stage IV or Dukes’ stage D disease, the 5-year survival rate is poor (approximately 5%).
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 143
Correct
-
A 29-year-old pregnant woman suffering from hyperemesis gravidarum is prescribed metoclopramide. What is the mechanism of action of metoclopramide?
Your Answer: Dopamine antagonist
Explanation:Metoclopramide is a potent dopamine-receptor antagonist with anti-emetic and prokinetic properties. It is therefore commonly used to treat nausea and vomiting, and to facilitate gastric emptying in patients with gastric stasis. The anti-emetic action of metoclopramide is due to its antagonist activity at D2 receptors in the chemoreceptor trigger zone (CTZ) in the central nervous system. Common adverse drug reactions associated with metoclopramide include restlessness (akathisia), and focal dystonia.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 144
Incorrect
-
A textbook of cardiac surgery explains that while doing a left pneumonectomy, a surgeon must be careful to avoid injury to a vital structure that leaves an impression on the mediastinal surface of the left lung. Which structure is it referring to?
Your Answer: Azygos vein
Correct Answer: Aortic arch
Explanation:Structures that leave an impression on the mediastinal surface of the left lung include: the oesophagus, subclavian artery, brachiocephalic vein, first rib, thymus, the heart, the diaphragm, descending aorta and arch of the aorta. The other structures form an impression on the mediastinal aspect of the right lung.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 145
Correct
-
A 59-year old gentleman admitted for elective cholecystectomy was found to have a haemoglobin 12.5 g/dl, haematocrit 37%, mean corpuscular volume 90 fl, platelet count 185 × 109/l, and white blood cell count 32 × 109/l; along with multiple, small mature lymphocytes on peripheral smear. The likely diagnosis is:
Your Answer: Chronic lymphocytic leukaemia
Explanation:CLL or chronic lymphocytic leukaemia is the most common leukaemia seen in the Western world. Twice more common in men than women, the incidence of CLL increases with age. About 75% cases are seen in patients aged more than 60 years. The blood, marrow, spleen and lymph nodes all undergo infiltration, eventually leading to haematopoiesis (anaemia, neutropenia, thrombocytopenia), hepatomegaly, splenomegaly and decreased production of immunoglobulin. In 98% cases, CD+5 B cells undergo malignant transformation.
Often diagnosed on blood tests while being evaluated for lymphadenopathy, CLL causes symptoms like fatigue, anorexia, weight loss, pallor, dyspnoea on exertion, abdominal fullness or distension. Findings include multiple lymphadenopathy with minimal-to- moderate hepatomegaly and splenomegaly. Increased susceptibility to infections is seen. Herpes Zoster is common. Diffuse or maculopapular skin infiltration can also be seen in T-cell CLL.
Diagnosis is by examination of peripheral blood smear and marrow: hallmark being a sustained, absolute leucocytosis (>5 ×109/l) and increased lymphocytes in the marrow (>30%). Other findings can include hypogammaglobulinemia (<15% of cases) and, rarely, raised lactate dehydrogenase (LDH). Only 10% cases demonstrate moderate anaemia and/or thrombocytopenia.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 146
Correct
-
Raised alkaline phosphatase and positive antimitochondrial antibody indicates which of the following conditions presenting with pruritus?
Your Answer: Primary biliary cirrhosis
Explanation:An autoimmune disease, primary biliary cirrhosis results in destruction of intrahepatic bile ducts. This leads to cholestasis, cirrhosis and eventually, hepatic failure. Symptoms includes fatigue, pruritus and steatorrhea. Increased IgM levels, along with antimitochondrial antibodies are seen in the serum. Liver biopsy is diagnostic, and also aids in staging of disease.
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This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
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Question 147
Incorrect
-
A 27 year old women had developed a darker complexion following a vacation to India. She had no erythema or tenderness. Her skin colour returned to normal over a period of 1 month. Which of the these substances is related to the biochemical change mentioned above?
Your Answer: Homogentisic acid
Correct Answer: Tyrosine
Explanation:The tanning process can occur due to UV light exposure as a result of oxidation of tyrosine to dihydrophenylalanine with the help of the tyrosinase enzyme within the melanocytes. Hemosiderin can impart a brown colour due to breakdown of RBC but its usually due to a trauma and is known as haemochromatosis.
Lipofuscin gives a golden brown colour to the cell granules not the skin.
Homogentisic acid is part of a rare disease alkaptonuria, with characteristic black pigment deposition within the connective tissue.
Copper can impart a brown golden colour, but is not related to UV light exposure.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 148
Correct
-
A 45-year old gentleman presented to the emergency department at 5.00 AM with pain in his left flank. The pain began suddenly and presented in waves throughout the night. Urine examination was normal except for presence of blood and few white blood cells. The pH and specific gravity of the urine were also found to be within normal range. What is the likely diagnosis?
Your Answer: Ureteric calculus
Explanation:A calculus in the ureter, if less than 5mm in diameter is likely to pass spontaneously. However, a larger calculus irritates the ureter and may become lodged, leading to hydroureter and/or hydronephrosis. Likely sites where the calculus might get lodged, include pelviureteric junction, distal ureter at the level of iliac vessels and the vesicoureteric junction. An obstruction can result in reduced glomerular filtration. There can be deterioration in renal function due to hydronephrosis and a raised glomerular pressure, leading to poor renal blood flow. Permanent renal dysfunction usually takes about 4 weeks to occur. Secondary infection can also occur in chronic obstruction.
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This question is part of the following fields:
- Pathology
- Renal
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Question 149
Correct
-
The Henderson–Hasselbalch equation describes the derivation of pH as a measure of acidity. According to this equation, the buffering capacity of the system is at maximum when the number of free anions compared with undissociated acid is:
Your Answer: Equal
Explanation:In 1908, Lawrence Joseph Henderson wrote an equation describing the use of carbonic acid as a buffer solution. Later, Karl Albert Hasselbalch re-expressed that formula in logarithmic terms, resulting in the Henderson–Hasselbalch equation. The equation is also useful for estimating the pH of a buffer solution and finding the equilibrium pH in acid–base reactions. Two equivalent forms of the equation are: pH = pKa + log10 [A–]/[HA] or pH = pKa + log10 [base]/[acid]. Here, pKa is − log10(Ka) where Ka is the acid dissociation constant, that is: pKa = –log10(Ka) = –log10 ([H3 O+][A–]/[HA]) for the reaction: HA + H2 O ≈ A– + H3 O+ In these equations, A– denotes the ionic form of the relevant acid. Bracketed quantities such as [base] and [acid] denote the molar concentration of the quantity enclosed. Maximum buffering capacity is found when pH = pKa or when the number of free anions to undissociated acid is equal and buffer range is considered to be at a pH = pKa ± 1.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 150
Correct
-
The operating surgeon notices a structure lying alongside a herniated mass whilst repairing an indirect inguinal hernia in a female patient. Which structure could this be?
Your Answer: Round ligament of the uterus
Explanation:The main structure traversing the inguinal canal in women is the round ligament. In men, it is the spermatic cord.
The iliohypogastric nerve innervates the abdominal wall and runs between the transversus abdominis and internal oblique muscles before piercing the internal oblique at the anterior superior iliac spine to run between the internal and external obliques.
The inferior epigastric artery is between the peritoneum and the transversus abdominis creating the lateral umbilical fold.
The ovarian artery and the ovarian vein are branches from the descending aorta and inferior vena cava that supply the ovary in the pelvic cavity.
The pectineal ligament is a thick fascial layer over the pectineal line of the pubis. It doesn’t traverse the canal.
The broad ligament if found on the lateral sides of the uterus.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 151
Correct
-
The circle of Willis is one of the cerebrovascular safeguards comprised of the left and the right posterior communicating artery. Which of the following arteries in the brain is connected to the posterior cerebral artery by these posterior communicating arteries?
Your Answer: Internal carotid artery
Explanation:The Circle of Willis is an anastomosis of cerebral arteries that are located at the base of the brain. The Circle of Willis is one of the important safeguards that ensure back up of blood supply to parts of the brain in case of any cerebrovascular accident. The Circle of Willis is made up of an anterior portion of arteries including; the anterior cerebral arteries. The anterior cerebral arteries are connected to the posterior portion of the circle of Willis by the anterior communicating artery. The posterior portion is made up of the posterior cerebral artery which branch off from the basilar artery. The posterior cerebral artery are connected to the anterior portion of the circle of Willis by the posterior communicating artery. The posterior communicating artery connects the posterior cerebral artery to the internal carotid artery. The circle of Willis receives blood supply from the left and right internal carotid arteries that continues as the middle cerebral artery and posteriorly from the two vertebral arteries that join to form the basilar artery.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 152
Correct
-
A surgeon ligates the left superior suprarenal artery whilst preforming a left adrenalectomy. Where does the left superior suprarenal artery originate?
Your Answer: Left inferior phrenic artery
Explanation:The superior suprarenal arteries arises from the inferior phrenic artery on either side.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 153
Incorrect
-
The renal tubule is the portion of the nephron that contains the fluid that has been filtered by the glomerulus. Which of the following substances is actively secreted into the renal tubules?
Your Answer: Chloride
Correct Answer: Potassium
Explanation:The renal corpuscle filters out solutes from the blood, delivering water and small solutes to the renal tubule for modification. In normal circumstances more than 90% of the filtered load of K is reabsorbed by the proximal tubules and loops of Henlé and almost all K appearing in the urine has been secreted by the late distal tubules and collecting tubules. So the rate of excretion is usually independent of the rate of filtration, but is closely tied to the rate of secretion and control of K excretion, largely accomplished by control of the secretion rate. Around 65–70% of the filtered potassium is reabsorbed along with water in the proximal tubule and the concentration of potassium in the tubular fluid varies little from that of the plasma.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 154
Incorrect
-
A 30-year-old woman known with Von Willebrand disease (vWD) has to undergo surgery. Which of these complications is most unlikely in this patient?
Your Answer: Easy bruising
Correct Answer: Hemarthrosis
Explanation:Von Willebrand disease (vWD) is an inherited haemorrhagic disorder characterised by the impairment of primary haemostasis. It is caused by the deficiency or dysfunction of a protein named von Willebrand factor. The most common manifestation due to the condition is abnormal bleeding. Complications include easy bruising, hematomas, epistaxis, menorrhagia, prolonged bleeding and severe haemorrhage. Hemarthrosis is a complication that is more commonly found in haemophilia.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 155
Incorrect
-
Which of the following muscle divide the posterior triangle of the neck into the occipital and the subclavian triangle?
Your Answer: Posterior belly of the digastric
Correct Answer: Inferior belly of the omohyoid
Explanation:The posterior triangle (or lateral cervical region) is a region of the neck bounded in front by the sternocleidomastoid; behind, by the anterior margin of the trapezius; inferiorly by the middle third of the clavicle and superiorly by the occipital bone. The posterior triangle is crossed, about 2.5 cm above the clavicle, by the inferior belly of the omohyoid muscle, which divides the space into two triangles: an upper or occipital triangle and a lower or subclavian triangle (or supraclavicular triangle).
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 156
Correct
-
A 58-year-old woman has had a headache, fever, lethargy and nausea for the last 10 days. He undergoes a CT scan which reveals a lesion in his frontal lobe, which, after a biopsy, is found to be formed by granulation tissue with collagenisation, gliosis and oedema. What's the most likely diagnosis?
Your Answer: Chronic brain abscess
Explanation:A cerebral abscess can result from direct extension of cranial infections, penetrating head trauma, haematogenous spread, or for unknown causes. An abscess forms when an area of cerebral inflammation becomes necrotic and encapsulated by glial cells and fibroblasts. Oedema around the abscess can increase the intracranial pressure. Symptoms result from increased intracranial pressure and mass effects. In a CT scan, an abscess appears as an oedematous mass with ring enhancement.
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This question is part of the following fields:
- Neurology
- Pathology
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Question 157
Incorrect
-
In relation to the muscles of facial expression, It is true to say:
Your Answer: The mandibular nerve, a branch of the trigeminal nerve innervates some of the facial muscles
Correct Answer: They are in the same subcutaneous plane as the platysma muscle
Explanation:The facial muscles generally originate from the facial bones and attach to the skin, in the same plane as the platysma muscle. They are all innervated by cranial nerve VII (the facial nerve). The occipitofrontalis muscle consists of two parts: The occipital belly, near the occipital bone, and the frontal belly, near the frontal bone.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 158
Correct
-
Which of the following abnormalities can be seen in patients with hypermagnesemia?
Your Answer: Respiratory depression
Explanation:Hypermagnesemia is an electrolyte disturbance in which there is a high level of magnesium in the blood. It is defined as a level greater than 1.1 mmol/L. Symptoms include weakness, confusion, decreased breathing rate, and cardiac arrest.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
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Question 159
Incorrect
-
What are some of the derivatives of the second pharyngeal arch?
Your Answer: Stylopharyngeus muscle
Correct Answer: Stylohyoid muscle
Explanation:Also known as the hyoid arch, it forms the side and front of the neck. From its cartilage develops the styloid process, stylohyoid ligament and lesser cornu of the hyoid bone. The muscular derivatives include the muscles of facial expression, stapedius, stylohyoid and the posterior belly of the digastric. All these are innervated by cranial nerve VII but migrate into the area of the mandibular arch.
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This question is part of the following fields:
- Anatomy
- Embryology
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Question 160
Incorrect
-
Which of the following has the least malignant potential?
Your Answer: Tubular adenoma
Correct Answer: Hyperplastic polyp
Explanation:Non-neoplastic (non-adenomatous) colonic polyps include hyperplastic polyps, hamartomas, juvenile polyps, pseudopolyps, lipomas, leiomyomas and others.
An autosomal dominant condition, Peutz–Jeghers syndrome is a disease that is characterized by multiple hamartomatous polyps in the stomach, small bowel and colon. Symptoms of this syndrome include hyperpigmentation of the skin and mucous membranes, especially of the lips and gums.
Juvenile polyps develop in children, and once they outgrow their blood supply, they autoamputate around puberty. In cases of uncontrolled bleeding or intussusception, treatment is needed.
Inflammatory polyps and pseudopolyps occur in chronic ulcerative colitis and Crohn’s disease. There is an increased risk of cancer with multiple juvenile polyps (not with sporadic polyps).
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This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
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Question 161
Correct
-
Which statement is true regarding the diaphragmatic openings:
Your Answer: The thoracic duct passes through the opening at T12
Explanation:The diaphragmatic openings are:
T8 – opening for the inferior vena cavaand the right phrenic nerve
T10 – opening for the oesophagusand the left gastric artery and vein
T12 – opening for the aorta, the thoracic duct and azygos vein.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 162
Correct
-
A cerebellar tremor can be differentiated from a Parkinsonian tremor in that:
Your Answer: It only occurs during voluntary movements
Explanation:Cerebellar disease leads to intention tremors, which is absent at rest and appears at the onset of voluntary movements. In comparison, Parkinson’s tremor is present at rest. Frequency of tremor is a less reliable means to differentiate between the two as the oscillation amplitude of the tremor is not constant throughout a voluntary action.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 163
Incorrect
-
Which of the following factors will not affect the wound healing process in a young women who suffered serious burns to her chest and hands?
Your Answer: Zinc
Correct Answer: Vitamin A deficiency
Explanation:Healing can be sped-up or slowed down due to various reasons: 1. blood supply, 2. infection, 3. denervation, 4. collection of blood/hematoma, 5. mechanical stress, 6. foreign body, 7. techniques used during surgery and 8. dressing of the wound. Other systemic factors include 1. nutrition e.g. deficiency of zinc, vitamin C, protein deficiency, 2. metabolic status, 3. circulatory status and 4. hormonal influence
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 164
Correct
-
Selective destruction of which of the following cells will affect antibody synthesis?
Your Answer: Plasma cells
Explanation:Plasma cell are memory cells. After the antigen Is engulfed by the B cells it is presented to the CD4+ helper cells via the MCH II receptor and this leads to their activation which in turn stimulates the B cells to form antibodies against that specific antigen. Some B cells differentiate into plasma cells also called memory cells that get activated after subsequent infection.
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This question is part of the following fields:
- General
- Physiology
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Question 165
Correct
-
A 34-year-old Asian male presents with cervical lymphadenopathy. The patient is suspected to have tuberculous lymphadenopathy. Excision biopsy of one of the nodes showed granulomatous inflammation. Which histopathologic feature is most likely consistent with the diagnosis of tuberculosis?
Your Answer: Caseation necrosis
Explanation:The granulomas of tuberculosis tend to contain necrosis (caseating tubercles), but non-necrotizing granulomas may also be present. Multinucleated giant cells with nuclei arranged like a horseshoe (Langhans giant cells) and foreign body giant cells are often present, but are not specific for tuberculosis. A definitive diagnosis of tuberculosis requires identification of the causative organism by microbiological cultures.
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 166
Incorrect
-
Chest X-ray of a 45-year old gentleman with a week history of pleurisy showed a small pneumothorax with moderate-sized pleural effusion. Arterial blood gas analysis showed p(CO2) = 23 mmHg, p(O2) = 234.5 mmHg, standard bicarbonate = 16 mmol/l. What are we most likely dealing with?
Your Answer: Mixed acidosis
Correct Answer: Compensated respiratory alkalosis
Explanation:Normal pH with low p(CO2) and low standard bicarbonate could indicate either compensated respiratory alkalosis or a compensated metabolic acidosis. However, the history of hyperventilation for 5 days (pleurisy) favours compensated respiratory alkalosis. Compensated metabolic acidosis would have been likely in a diabetic patient with fever, vomiting and high glucose (diabetic ketoacidosis).
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 167
Incorrect
-
The following structures DO NOT lie between the layers of the mesosalpinx except for the?
Your Answer: Uterus
Correct Answer: Fallopian tube
Explanation:Mesosalpinx is the portion of the broad ligament that stretches from the fallopian tube to the ovary and contains the uterine tubes between it’s layers.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 168
Correct
-
A 62-year-old man presented with a persistent cough and weight loss. Chest x-ray demonstrated widespread nodular opacities. After a bronchoalveolar lavage, atypical cells were detected. Which is the most probable diagnosis?
Your Answer: Bronchioalveolar carcinoma
Explanation:Bronchioloalveolar carcinoma (BAC) is a term used to define a particular subtype of adenocarcinoma which develops in cells near the alveoli, in the outer regions of the lungs. On a chest X-ray it can appear as a single peripheral spot or as scattered spots throughout the lungs. Symptoms include cough, haemoptysis, chest pain, dyspnoea and loss of weight.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 169
Incorrect
-
In which of the following compartments of the femoral sheath is the femoral artery located?
Your Answer: Medial compartment
Correct Answer: Lateral compartment
Explanation:The femoral sheath also known as the crural sheath is made up of three compartments; lateral, intermediate and the medial. The femoral artery is contained in the lateral compartment of the femoral sheath while the femoral vein is in the intermediate compartment.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 170
Correct
-
Which of the following structures, is the area in which the superior cerebral veins drain into?
Your Answer: Superior sagittal sinus
Explanation:The superior cerebral veins are predominantly located on the superior aspect of the brain. They are 8 to 12 in number and they drain the lateral, medial and superior aspects of the cerebral hemispheres.
These veins drain into the superior sagittal sinus, also known as the superior longitudinal sinus – which is located along the attached margin of the falx cerebri.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 171
Correct
-
A 25 year old primi gravida lady was scheduled for a regular antenatal check up. During the vaginal exam of this lady, the registrar discovered a malignant growth on the anterior wall of her vagina. Which of the following structures, adjacent to the vagina, is likely to be involved as well?
Your Answer: Fundus of the bladder
Explanation:The fundus of the bladder is related anatomically to the anterior surface of the vagina and the urethra as well. If there was a malignant growth in the anterior surface of the vagina, then most likely the fundus of the bladder would be involved as well aspotentially the urethra.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 172
Correct
-
Which one of the following muscles is innervated by the facial nerve?
Your Answer: Buccinator
Explanation:Buccinator is a muscle of facial expression and is therefore innervated by the facial nerve. The lateral pterygoid, masseter, anterior belly of digastric and temporalis are all muscles of mastication and therefore innervated by the mandibular division of the trigeminal nerve.
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This question is part of the following fields:
- Anatomy
- Head & Neck; Neurology
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Question 173
Correct
-
The transverse colon has two curvatures known as the colic flexures on each side of its lateral ends, the right and left. The left colic flexure found on the side of the descending colon is attached to an organ superiorly by a mesenteric ligament. Which organ is this?
Your Answer: Spleen
Explanation:The left colic flexure is the bend of the transverse colon as it continues to form the descending colon on the left upper quadrant. The spleen is located on the superior aspect of the left colic flexure. It is commonly referred to as the splenic flexure because of its relation o the spleen superiorly.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 174
Correct
-
Which of the following features is indicative of poor prognosis in a case of breast carcinoma?
Your Answer: Axillary lymph node metastases
Explanation:Lymphatic spread indicates poor prognosis. Presence of family history is not a prognostic factor despite being linked to higher incidence. Aneuploidy is a poor prognostic factor. A breast tumour positive for oestrogen receptors is a good prognostic factor as it increases the responsiveness of the tumour to certain therapies. In-situ tumours carry the best prognosis.
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This question is part of the following fields:
- Pathology
- Women's Health
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Question 175
Correct
-
A 58-year-old woman presents with signs of inflammation in the first metatarsophalangeal joint: redness, swelling and pain. The analysis of synovial fluid reveals needle-shaped, strongly negatively birefringent crystals. What's the most likely diagnosis in this case?
Your Answer: Gout
Explanation:Gout is a rheumatic disease caused by the precipitation of monosodium urate crystals into tissues, usually joints. This causes acute or chronic pain; the acute illness initially affects only one joint, often the first metatarsophalangeal joint. The diagnosis of the disease requires the identification of crystal in the synovial fluid. These crystals are needle-shaped and strongly negatively birefringent.
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 176
Correct
-
The specialist registrar, while performing the repair of an infrarenal abdominal aortic aneurysm, decides not to re-implant the inferior mesenteric artery into the repaired abdominal aorta. She says that an anastomotic artery running along the border of the large intestine is good enough to supply blood to the territory of the inferior mesenteric artery. Which vessel is she referring to?
Your Answer: Marginal
Explanation:The marginal artery is a key anastomosis for the large intestine that runs around the border of the large intestine and is formed by the anastomosis of the branches of the ileocolic artery, right colic artery, middle colic artery, left colic artery and sigmoid artery. If a small artery is occluded, these branches allow blood to reach all segments of the colon.
The arcades are anastomotic loops between the arteries that provide alternative pathways for blood flow. They are more prominent in the small intestine than the large intestine.
Arteriae rectae are small branches that run from the marginal artery to reach the colon.
The ileocolic artery is the branch of the superior mesenteric artery that supplies the caecum, appendix and terminal part of the ileum.
The coronary arteries supply blood to the heart.
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This question is part of the following fields:
- Abdomen
- Anatomy
-
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Question 177
Correct
-
A patient underwent surgical excision of mass in the right carotid triangle. One day after the surgery patient complained of numbness of the skin over the right side of the neck. Injury to the cervical plexus of nerves is suspected. What is the possible nerve affected in this patient?
Your Answer: Transverse cervical
Explanation:The transverse cervical nerve (superficial cervical or cutaneous cervical) arises from the second and third spinal nerves, turns around the posterior border of the sternocleidomastoid and, passing obliquely forward beneath the external jugular vein to the anterior border of the muscle, it perforates the deep cervical fascia, and divides beneath the platysma into the ascending and descending branches. It provides cutaneous innervation to this area.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 178
Incorrect
-
A patient presents with loss of pain and temperature sensation in the left leg. He is likely to have a lesion involving:
Your Answer: Left lateral spinothalamic tract
Correct Answer: Right lateral spinothalamic tract
Explanation:The spinothalamic tract is a sensory pathway originating in the spinal cord that transmits information to the thalamus. There are two main parts of the spinothalamic tract: the lateral spinothalamic tract transmits pain and temperature and the anterior spinothalamic tract transmits touch (crude touch). The decussation of this pathway occurs at the level of the spinal cord. Hence, a unilateral lesion of the lateral spinothalamic tract causes contralateral loss of pain and temperature.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 179
Correct
-
The chest X-ray of an 10-year-old boy, that presented with low-grade fever and cough, revealed hilar enlargement and parenchymal consolidation in the middle lobes. These X-ray findings are more typical for which of the following diagnoses?
Your Answer: Pulmonary tuberculosis
Explanation:Primary pulmonary tuberculosis is seen in patients exposed to Mycobacterium tuberculosis for the firs time. The main radiographic findings in primary pulmonary tuberculosis include homogeneous parenchymal consolidation typically in the lower and middle lobes, lymphadenopathy, miliary opacities and pleural effusion.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 180
Correct
-
One of the following structures is contained in the anterior compartment of the lower leg. Which is it?
Your Answer: Extensor hallucis muscle
Explanation:The lower leg is made up of four fascial compartments separated from one another by septa that contain the muscles of the lower leg. The four compartments are ; anterior, lateral, deep posterior and superficial posterior compartments.
These are the compartments and there contents:
i) Anterior compartment: Tibialis anterior muscle, extensor hallucis longus muscle, extensor digitorum longus muscle, peroneus tertius muscles, deep fibular nerve and anterior tibial blood vessels
ii) Lateral compartment: Fibularis longus muscle, brevis muscles and superficial fibular nerve
iii) Deep posterior compartment: Tibialis posterior m., flexor hallucis longus m., flexor digitorum longus m. ,popliteus m. , tibial nerve, posterior tibial artery and posterior tibial vessels such as the fibular artery.
iv) Superficial posterior compartment: Gastrocnemius m., soleus m., plantaris m., medial sural cutaneous nerve
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 181
Correct
-
Question 182
Correct
-
A pedestrian sustained a left fibula fractured following a hit-and-run. X-rays showed that there was a transverse fracture of the upper end of the fibula. It was manifested clinically by inability to flex his foot at the ankle joint plus weak extension of the phalanges. What nerve is suspected to be injured in such a case?
Your Answer: Deep peroneal
Explanation:The deep peroneal nerve supplies the muscles allowing for flexion of the foot at the ankle joint, namely the tibialis anterior and peroneus tertius muscles. The peroneus tertius, peroneus brevis, and peroneus longus evert the foot, whereas the tibialis anterior and tibialis posterior invert the foot. Fibres of the deep peroneal nerve originate from L4, L5, and S1.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 183
Correct
-
An explorative laparotomy is done on a 23 year old following a gunshot abdominal injury through the right iliac fossa. It is found that the ileocolic artery is severed and the bullet had perforated the caecum. From which branch does the ileocolic artery originate?
Your Answer: Superior mesenteric artery
Explanation:Ileocolic artery branches off from the superior mesenteric artery. It then divides to give a superior and inferior branch.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 184
Incorrect
-
If your EEG shows waves with a frequency range of 8-12 Hz, the waves most likely to be seen are:
Your Answer: Delta
Correct Answer: Alpha
Explanation:Electroencephalography (EEG) is the neurophysiological measurement of the electrical activity of the brain. It is done by placing electrodes on the scalp or subdurally. In reality, the electrical currents are not measured, but rather the voltage differences between different parts of the brain. Four major types of EEG activity are recognized, which are alpha, beta, delta and theta.
Alpha waves, also known as Berger’s waves ranges in frequency from 8-12 Hz. Best detected with eyes closed, alpha waves are characteristic of a relaxed, alert state of consciousness. An alpha-like normal variant called mu is sometimes seen over the motor cortex (central scalp) and attenuates with movement or, rather, with the intention to move.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 185
Correct
-
Risk factors for hepatocellular carcinoma do NOT include:
Your Answer: Heptitis E
Explanation:Risk factors for hepatocellular carcinoma include hepatitis B and C, aflatoxin, anabolic steroids, alcohol cirrhosis and primary liver disease.
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This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
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Question 186
Correct
-
A 30 year old gym coach presented to the surgical out patient clinic with a lump in the inguinal region. He was booked for surgery, during which, the surgeon opened the inguinal region and found a hernial sac with a small segment of intestine projecting through the abdominal wall. It was located just above the inguinal ligament and lateral to the inferior epigastric vessels. What type of hernia was this?
Your Answer: An indirect inguinal hernia
Explanation:An indirect inguinal hernia exits the abdominal cavity lateral to the inferior epigastric vessels and enters the inguinal canal through the deep inguinal ring. These are the most common types of hernias often caused by heavy weigh lifting. Direct inguinal hernias exit the abdominal cavity medial to the inferior epigastric vessels through weak fascia.
Congenital inguinal hernias are indirect hernias that occur due to persistence of the processus vaginalis.
Femoral hernias occur when abdominal viscera push through the femoral ring in the femoral canal.
Incisional hernia occurs after surgery when the omentum or organ protrudes through a previous site of incision.
Obturator hernia are a very rare type of hernia where the pelvic or abdominal contents protrude through the obturator foramen.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 187
Correct
-
Which of these illnesses is most likely to precede Guillain-Barré syndrome?
Your Answer: Viral pneumonia
Explanation:Guillain–Barré syndrome (GBS) is characterized by a rapid-onset muscle weakness caused by the immune system damaging the peripheral nervous system. In about two-thirds of patients, the syndrome begins 5 days to 3 weeks after an infectious disease, surgery or vaccination. Infection is the trigger in over 50% of patients; common pathogens include Campylobacter jejuni, enteric viruses, herpesviruses (including cytomegalovirus and those causing infectious mononucleosis) and Mycoplasma species. The underlying mechanism involves an autoimmune disorder in which the body’s immune system mistakenly attacks the peripheral nerves and damages their myelin insulation, although the cause for this is still unknown.
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This question is part of the following fields:
- Neurology
- Pathology
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Question 188
Incorrect
-
The collaborative effort of the lateral pterygoid muscles produces which action on the jaw?
Your Answer: Retract the mandible
Correct Answer: Protrude the mandible
Explanation:The combined effort of the lateral pterygoid muscles results in the protrusion of the mandible. The lateral pterygoid muscle is a muscle of mastication located superiorly to the medial pterygoid muscle and has two heads. The superior head originates on the infratemporal surface and infratemporal crest of the greater wing of the sphenoid bone, and the inferior head on the lateral surface of the lateral pterygoid plate. The insertion of this muscle is on the front margin of the articular disc of the temporomandibular joint. The unilateral contraction of the pterygoid muscle results in the laterotrusion of the mandible. It is important to note that the lateral pterygoid muscle is the only muscle of mastication that can open the jaw.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 189
Incorrect
-
Which of the following is a likely cause of jaundice?
Your Answer: Common bile duct obstruction if the serum amino transferases are elevated and alkaline phosphatase is low
Correct Answer: Hepatic disease if plasma albumin is low and serum aminotransferase elevations > 500 units
Explanation:Jaundice can occur due to any of the possible causes and treatment depends upon diagnosing the correct condition. Mild hyperbilirubinemia with normal levels of aminotransferase and alkaline phosphatase is often unconjugated (e.g., due to haemolysis or Gilbert’s syndrome rather than hepatobiliary disease). Moderate or severe hyperbilirubinemia along with increased urinary bilirubin (bilirubinuria), high alkaline phosphatase or aminotransferase levels suggest hepatobiliary disease. Hyperbilirubinemia produced by any hepatobiliary disease is largely conjugated. In this case, other blood tests include hepatitis serology for suspected hepatitis, prothrombin time (PT) or international normalised ratio (INR), albumin and globulin levels, and antimitochondrial antibody levels (suspected primary biliary cirrhosis). Low albumin and high globulin levels suggest chronic rather than acute liver disease. In cases where there is only a an elevation of alkaline phosphatase, γ-glutamyl transpeptidase (GGT) levels should be checked – the levels of which will be found high in hepatobiliary disease, but not in bone disorder which can also lead to elevated alkaline phosphatase levels. In diseases of hepatobiliary origin, aminotransferase elevations > 500 units suggest a hepatocellular cause, whereas disproportionate increases of alkaline phosphatase (e.g., alkaline phosphatase > 3 times normal and aminotransferase < 200 units) suggest cholestasis. Because hepatobiliary disease alone rarely causes bilirubin levels > 30 mg/dl, higher levels are suggestive of a combination of severe hepatobiliary disease and haemolysis or renal dysfunction. Imaging is best for diagnosing infiltrative and cholestatic causes of jaundice. Liver biopsy is rarely needed, but can be of use in intrahepatic cholestasis and in some types of hepatitis.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 190
Correct
-
Under normal conditions, what is the major source of energy of cardiac muscles?
Your Answer: Fatty acids
Explanation:Under basal conditions, most of the energy needed by cardiac muscle for metabolism is derived from fats (60%), 35% by carbohydrates, and 5% by ketones and amino acids. However, after intake of large amounts of glucose, lactate and pyruvate are mainly used. During prolonged starvation, fat acts as the primary source. 50% of the used lipids are sourced from circulating fatty acids.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 191
Correct
-
What is the pH of freshly formed saliva at ultimate stimulation?
Your Answer: 8
Explanation:Saliva has four major components: mucus (lubricant), α-amylase (enzyme that initiates digestion of starch), lingual lipase (enzyme that begins fat digestion), and a slightly alkaline electrolyte solution for moistening food. As the secretion rate of saliva increases, its osmolality increases. Moreover, the pH changes from slightly acidic (at rest) to basic (pH 8) at ultimate stimulation. This occurs due to increase of HCO3-. Amylase and mucus also increase in concentration after stimulation.
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This question is part of the following fields:
- Gastroenterology
- Physiology
-
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Question 192
Correct
-
A cancer patient was found to have a radio resistant tumour. Which tumour does the patient most likely have?
Your Answer: Liposarcoma
Explanation:Liposarcoma is a cancer that arises in fat cells in deep soft tissue. Commonly it occurs inside the thigh or retroperitoneum. It usually affects middle-aged and older adults, over 40 years. Liposarcoma is the most common soft-tissue sarcoma. It is very radio resistant. Five-year survival rates vary from 100% to 56% based on histological subtype.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 193
Correct
-
Which of the following is true about a patient who has undergone total colectomy and ileostomy?
Your Answer: Following total colectomy and ileostomy, the volume and water content of ileal discharge decreases over time
Explanation:After a patient has undergone total colectomy and ileostomy, the volume of ileal discharge, along with its water content gradually decreases over time. Post surgery, most patients can live a normal life. Iron and vitamin B12 absorption do not take place in the colon and hence are not affected significantly by a colectomy.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 194
Incorrect
-
The mechanism of action of streptokinase involves:
Your Answer: Direct lysis of the clot
Correct Answer: Direct conversion of plasminogen to plasmin
Explanation:Streptokinase is an enzyme that is produced by group A beta haemolytic streptococcus and is an effective and cost efficient method for the dissolution of a clot used in cases of MI and pulmonary embolism. It works by directly converting plasminogen to plasmin which breaks down the blood components in the clot and fibrin, dissolving the clot. Streptokinase is a bacterial product and thus the body will develop immunity against it.
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This question is part of the following fields:
- General
- Physiology
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Question 195
Incorrect
-
During cardiac catheterisation, if the blood sample from the catheter shows an oxygen saturation of 70%, and the pressure ranging from 12 to 24 mm Hg, it implies that the catheter tip is located in the:
Your Answer: Right atrium
Correct Answer: Pulmonary artery
Explanation:Normal values for various parameters are as follows:
Systolic arterial blood pressure (SBP): 90–140 mmHg.
Diastolic arterial blood pressure: 60–90 mmHg.
Mean arterial blood pressure (MAP): SBP + (2 × DBP)/3 (normal range: 70-105 mmHg).
Right atrial pressure (RAP): 2–6 mmHg.
Systolic right ventricular pressure (RVSP): 15–25 mmHg.
Diastolic right ventricular pressure (RVDP): 0–8 mmHg.
Pulmonary artery pressure (PAP): Systolic (PASP) is 15-25 mmHg and Diastolic (PADP) is 8–15 mmHg.
Pulmonary artery wedge pressure (PAWP): 6–12 mmHg.
Left atrial pressure (LAP): 6–12 mmHg.
Thus, the given value indicates that the position of catheter tip is likely to be in the pulmonary artery.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 196
Correct
-
During an anatomy revision session, medical students are told that the posterior wall of the rectus sheath ends in a thin curved margin whose concavity is directed downwards. What is the name of this inferior border of the rectus sheath?
Your Answer: Arcuate line
Explanation:The rectus sheath is a tendinous sheath that encloses the rectus abdominis muscle. It covers the entire anterior surface however on the posterior surface of the muscle the sheath is incomplete ending inferiorly at the arcuate line. Below the arcuate line, the rectus abdominis is covered by the transversalis fascia. The linea alba is a band of aponeurosis on the midline of the anterior abdominal wall, which extends from the xiphoid process to the pubic symphysis. It is formed by the combined abdominal muscle aponeuroses. This is a useful site for midline incision during abdominal surgery because it does not carry many blood vessels. All of the other answer choices are related to the inguinal canal.
The falx inguinalis (sometimes called the inguinal falx or conjoint tendon), is the inferomedial attachment of the transversus abdominis with some fibres of the internal abdominal oblique – it contributes to the posterior wall of the inguinal canal.
The inguinal ligament is the ligament that connects the anterior superior iliac spine with the pubic tubercle – it makes the floor of the inguinal canal.
The internal (deep) inguinal ring is the entrance to the inguinal canal, where the transversalis fascia pouches out and creates an opening through which structures can leave the abdominal cavity.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 197
Correct
-
During gastrectomy, the operating surgeon ligates the short gastric arteries along the greater curvature of the stomach. Where do the short gastric arteries branch from?
Your Answer: Splenic artery
Explanation:Short gastric arteries arise from the splenic artery at the end or from its terminal divisions. They are about 5 or 7 in number, passing from the left to the right in between the layers of the gastrosplenic ligament to be distributed along the greater curvature of the stomach.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 198
Incorrect
-
A TRUE statement regarding abolition of the cephalic phase of pancreatic secretion is that it:
Your Answer: Will result in 10% reduction in maximal pancreatic secretion
Correct Answer: Will result after vagotomy
Explanation:Recognition and integration of the sight, smell and taste of food triggers the cephalic phase of pancreatic secretion, causing an increase in pancreatic HCO3- and enzyme secretion. The degree of enzyme secretion in this phase is about 50% of the maximal response seen with exogenous CCK and secretin. The vagus nerve regulates the secretion through the cholinergic fibres innervating the acinar cells of the pancreas, and through peptidergic nerve fibres, which innervate ductal cells.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 199
Correct
-
In a study, breast lumps were analysed to determine the characteristic of malignant neoplasm on biopsy. What microscopic findings are suggestive of malignancy?
Your Answer: Invasion
Explanation:Invasion is suggestive of malignancy and an even better option would have been metastasis. Pleomorphism is found in both benign and malignant neoplasms along with atypia and anaplasia. A height nuclear/cytoplasmic ratio is suggestive of malignancy but not the best indicator. Malignant tumours are aggressive and growth rapidly. Necrosis can be seen in benign tumours if they deplete their blood supply.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 200
Incorrect
-
A 68-year-old woman complains of headaches, dizziness, and memory loss. About a month ago, she fell from a staircase but only suffered mild head trauma. What is the most likely diagnosis in this case?
Your Answer: Subarachnoid haemorrhage
Correct Answer: Chronic subdural haematoma
Explanation:A quarter to a half of patients with chronic subdural haematoma have no identifiable history of head trauma. If a patient does have a history of head trauma, it usually is mild. The average time between head trauma and chronic subdural haematoma diagnosis is 4–5 weeks. Symptoms include decreased level of consciousness, balance problems, cognitive dysfunction and memory loss, motor deficit (e.g. hemiparesis), headache or aphasia. Some patients present acutely. They usually result from tears in bridging veins which cross the subdural space, and may cause an increase in intracranial pressure (ICP).
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This question is part of the following fields:
- Neurology
- Pathology
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SESSION STATS - PERFORMANCE PER SPECIALTY
