-
Question 1
Correct
-
Gram positive bacteria differ from gram negative bacteria due to the presence of which of the following structures?
Your Answer: Outer membrane
Explanation:The reason bacteria are either Gram-positive or Gram-negative is due to the structure of their cell envelope (the cell envelope is defined as the cell membrane and cell wall plus an outer membrane, if one is present.) Gram-positive bacteria, for example, retain the crystal violet due to the amount of peptidoglycan in the cell wall. It can be said therefore that the Gram-stain procedure separates bacteria into two broad categories based on structural differences in the cell envelope.
-
This question is part of the following fields:
- Microbiology
- Pathology
-
-
Question 2
Correct
-
Extracellular body fluid as compared with intracellular body fluid:
Your 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.
-
This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
-
-
Question 3
Correct
-
Medulloblastoma usually occurs in children between 5 to 9 years old. Where does medulloblastoma commonly originate from?
Your Answer: Cerebellar vermis
Explanation:Medulloblastoma is the most common malignant brain tumour in children, accounting for 10-20% of primary CNS neoplasms. Most of the tumours originate in the cerebellar vermis.
-
This question is part of the following fields:
- Neoplasia
- Pathology
-
-
Question 4
Correct
-
The third branch of the maxillary artery lies in which fossa?
Your Answer: Pterygopalatine fossa
Explanation:The maxillary artery supplies deep structures of the face. It branches from the external carotid artery just deep to the neck of the mandible. It is divided into three portions:
– The first or mandibular portion (or bony portion) passes horizontally forward, between the neck of the mandible and the sphenomandibular ligament.
– The second or pterygoid portion (or muscular portion) runs obliquely forward and upward under cover of the ramus of the mandible, on the surface of the lateral pterygoid muscle; it then passes between the two heads of origin of this muscle and enters the fossa.
– The third portion lies in the pterygopalatine fossa in relation to the pterygopalatine ganglion. This is considered the terminal branch of the maxillary artery. Branches from the third portion includes: the sphenopalatine artery, descending palatine artery, infraorbital artery, posterior superior alveolar artery, artery of pterygoid canal, pharyngeal artery, middle superior alveolar artery and anterior superior alveolar artery.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 5
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.”
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 6
Correct
-
Increased resistance to flow of blood in cerebral vessels is most likely seen in:
Your Answer: Elevation in systemic arterial pressure from 100 to 130 mmHg
Explanation:Constant cerebral blood flow is maintained by autoregulation in the brain, which causes an increase in local vascular resistance to offset an increase in blood pressure. There will be an increase in cerebral blood flow (and decrease in resistance to cerebral blood flow) with a decrease in arterial oxygen or an increase in arterial CO2. Similarly, a decrease in viscosity will also increase the blood flow. Due to increased brain metabolism and activity during a seizure, there will also be an increase in the cerebral blood flow.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 7
Correct
-
Which of these HLA alleles is most likely to be present in ankylosing spondylitis?
Your Answer: HLA-B27
Explanation:Ankylosing spondylitis usually appears between the ages of 20-40 years old and is more frequent in men. It is strongly associated with HLA-B27, along with other spondyloarthropathies, which can be remembered through the mnemonic PAIR (Psoriasis, Ankylosing spondylitis, Inflammatory bowel disease, and Reactive arthritis).
-
This question is part of the following fields:
- Orthopaedics
- Pathology
-
-
Question 8
Incorrect
-
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: Ulnar
Correct 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.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 9
Correct
-
A patient gives a history of dull discomfort in her abdomen associated with pain that she points to be on her right shoulder and right scapula. The following organs are most likely to be source of her pain:
Your Answer: Liver, duodenum and gallbladder
Explanation:Referred pain is felt at a point away from the source of the pain or the unpleasant sensation. It arises when a nerve is damaged or compressed at a point but the pain is felt at another site that is the territory of that nerve. Common abdominal causes of referred pain to the shoulder and the shoulder blade are the liver, duodenum and gall bladder.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 10
Correct
-
Which of these conditions is mithramycin used for?
Your Answer: Hypercalcaemia of malignancy
Explanation:Mithramycin or Plicamycin is a tricyclic pentaglycosidic antibiotic derived from Streptomyces strains. It inhibits RNA and protein synthesis by adhering to DNA. It is used as a fluorescent dye and as an antineoplastic agent. It is also used to reduce hypercalcaemia, especially caused by malignancy. Plicamycin is currently used in multiple areas of research, including cancer cell apoptosis and as a metastasis inhibitor.
-
This question is part of the following fields:
- Pathology
- Pharmacology
-
-
Question 11
Correct
-
Difficulty in retracting the foreskin of the penis in an uncircumcised male is known as:
Your Answer: Phimosis
Explanation:Phimosis is the inability to fully retract the foreskin of the penis in an uncircumcised male. It can be physiological in infancy, in which it could be referred to as ‘developmental non-retractility of the foreskin. However, it is almost always pathological in older children and men. Causes include chronic inflammation (e.g. balanoposthitis), multiple catheterisations, or forceful foreskin retraction. One of the causes is chronic balanitis xerotica obliterans. It leads to development of a ring of indurated tissue near the tip of the prepuce, which prevents retraction. Contributory factors include infections, hormonal and inflammatory factors. The recommended treatment includes circumcision.
-
This question is part of the following fields:
- Pathology
- Urology
-
-
Question 12
Correct
-
A surgeon trainee is assisting in an operation to ligate the ductus arteriosus. The consultant supervising explains that caution is required when placing a clamp on the ductus to avoid injury to an important structure immediately dorsal to it. To which structure is the consultant referring?
Your Answer: Left recurrent laryngeal nerve
Explanation:The left recurrent laryngeal nerve branches off the vagus and wraps around the aorta, posterior to the ductus arteriosus/ligamentum arteriosum from whence it courses superiorly to innervate the laryngeal muscles.
Accessory Hemiazygous vein is on the left side of the body draining the posterolateral chest wall and emptying blood into the azygos vein.
The left internal thoracic artery is branch of the left subclavian artery supplying blood to the anterior wall of the thorax.
Left phrenic nerve is lateral to the vagus nerve.
Thoracic duct: is behind the oesophagus, coursing between the aorta and the azygos vein in the posterior chest.
Right recurrent laryngeal nerve: loops around the right subclavian artery and is not in danger in this procedure.
-
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 13
Incorrect
-
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: Ileocolic
Correct 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.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 14
Correct
-
A 54 year old man fell off his bicycle. He felt a severe pain in his hand and wasn't able to move it. It was found that a carpal bone in the distal row was fractured. Which is the most likely bone?
Your Answer: Trapezium
Explanation:There are eight carpal bones which are arranged in two rows, proximal and distal; scaphoid, lunate, triquetral and pisiform are of proximal row. Trapezium, trapezoid, capitate and hamate are of the distal row.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 15
Correct
-
A 60-year-old man complains of pain in his left thigh. An X-ray reveals bowing of the affected femur, increased bone density, bony enlargement, abnormal bone architecture with coarse cortical trabeculations, and stress microfractures. Which is the most likely diagnosis in this case?
Your Answer: Paget’s disease of bone
Explanation:Paget’s disease of bone is a chronic disorder of the adult skeleton in which bone turnover is accelerated in localised areas, replacing normal matrix with softened and enlarged bone and causing gradual pain and deformity in some cases. It is more predominant in men over the age of 40. Characteristic X-ray findings include increased bone density, abnormal architecture with coarse cortical trabeculation or cortical thickening, bowing and bony enlargement; there might also be stress microfractures of the tibia or femur.
-
This question is part of the following fields:
- Orthopaedics
- Pathology
-
-
Question 16
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.
-
This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
-
-
Question 17
Incorrect
-
The middle meningeal artery is the largest among the arteries that supplies that dura mater of the brain. The middle meningeal artery is a branch of the?
Your Answer: Internal carotid artery
Correct Answer: Maxillary artery
Explanation:The middle meningeal artery is the largest of the three (paired) arteries that supply the meninges.
The middle meningeal artery is a large arterial branch of the maxillary artery which is a terminal branch of the external carotid artery. Upon originating, the middle meningeal artery passes through the foramen spinosum. In the skull, it courses in the middle cranial fossa where it provides several branches.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 18
Incorrect
-
Which is the most common benign germ-cell tumour that could occur in a premenopausal woman?
Your Answer: Myoma
Correct Answer: Dermoid cyst
Explanation:A dermoid cyst is a teratoma of a cystic nature that contains an array of developmentally mature and solid tissues. Dermoid cysts grow slowly and this type of cystic teratoma is nearly always benign.
-
This question is part of the following fields:
- Neoplasia
- Pathology
-
-
Question 19
Incorrect
-
Which of the following can occur even in the absence of brainstem co-ordination?
Your Answer: Vomiting
Correct Answer: Gastric emptying
Explanation:Although gastric emptying is under both neural and hormonal control, it does not require brainstem co-ordination. Increased motility of the orad stomach (decreased distensibility) or of the distal stomach (increased peristalsis), decreased pyloric tone, decreased duodenal motility or a combination of these, all increase the rate of gastric emptying. The major control mechanism for gastric emptying is through duodenal gastric feedback. The duodenum has receptors for the presence of acid, carbohydrate, fat and protein digestion products, osmolarity different from that of plasma, and distension. Activating these receptors decreases the rate of gastric emptying. Neural mechanisms involve both enteric and vagal pathways and a vagotomy impairs the gastric emptying regulation. CCK (cholecystokinin) slows gastric emptying at physiological levels of the hormone. Gastrin, secretin and glucose-1-phosphate also slow gastric emptying, but require higher doses.
-
This question is part of the following fields:
- Gastroenterology
- Physiology
-
-
Question 20
Correct
-
Calculate the cardiac output of a patient with the following measurements: oxygen uptake 200 ml/min, oxygen concentration in the peripheral vein 7 vol%, oxygen concentration in the pulmonary artery 10 vol% and oxygen concentration in the aorta 15 vol%.
Your Answer: 4000 ml/min
Explanation:The Fick’s principle states that the uptake of a substance by an organ equals the arteriovenous difference of the substance multiplied by the blood flowing through the organ. We can thus calculate the pulmonary blood flow with pulmonary arterial (i.e., mixed venous) oxygen content, aortic oxygen content and oxygen uptake. The pulmonary blood flow, systemic blood flow and cardiac output can be considered the same assuming there are no intracardiac shunts. Thus, we can calculate the cardiac output. Cardiac output = oxygen uptake/(aortic − mixed venous oxygen content) = 200 ml/min/(15 ml O2/100 ml − 10 ml O2/100 ml) = 200 ml/min/(5 ml O2/100 ml) = 200 ml/min/0.05 = 4000 ml/min.
It is crucial to remember to use pulmonary arterial oxygen content and not peripheral vein oxygen content, when calculating the cardiac output by Fick’s method.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 21
Incorrect
-
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.
-
This question is part of the following fields:
- Cardiovascular
- Pathology
-
-
Question 22
Correct
-
Electrophoresis is used to detect antibodies (immunoglobulins) in a blood sample from the umbilical artery of a new born. Which antibodies have the highest percentage in a new-born?
Your Answer: IgG
Explanation:IgG is a monomeric immunoglobulin. It is formed by two heavy chains and two light chains and has two binding sites. Its is the most abundant antibody that is equally distributed in the blood and the tissues. It is the only antibody that can pass through the placenta and thus the only antibody present in the baby after it is born. There are four subclasses: IgG1 (66%), IgG2 (23%), IgG3 (7%) and IgG4 (4%). IgG1, IgG3 and IgG4 cross the placenta easily
-
This question is part of the following fields:
- General
- Physiology
-
-
Question 23
Correct
-
Gastric acid secretion is stimulated by which of the following?
Your Answer: Gastrin
Explanation:Gastric acid secretion is stimulated by three factors:
– Acetylcholine, from parasympathetic neurones of the vagus nerve that innervate parietal cells directly
– Gastrin, produced by pyloric G-cells
– Histamine, produced by mast cells.
Gastric acid is inhibited by three factors:
– Somatostatin
– Secretin
– Cholecystokinin
-
This question is part of the following fields:
- Endocrine
- Physiology
-
-
Question 24
Incorrect
-
Which of the following muscles is solely contained in the anterior triangle of the neck and divides the anterior triangle into three smaller triangles?
Your Answer: Sternocleidomastoid
Correct Answer: Digastric
Explanation:The digastric muscle is a small muscle located under the jaw. It lies below the body of the mandible, and extends, in a curved form, from the mastoid process to the symphysis menti. The digastric divides the anterior triangle of the neck into three smaller triangles:
– The submaxillary triangle, bounded above by the lower border of the body of the mandible and a line drawn from its angle to the sternocleidomastoid, below by the posterior belly of the digastric and the stylohyoid and in front by the anterior belly of the digastric
– The carotid triangle, bounded above by the posterior belly of the digastric and stylohyoid, behind by the sternocleidomastoid and below by the omohyoid
– The suprahyoid or submental triangle, bounded laterally by the anterior belly of the digastric, medially by the midline of the neck from the hyoid bone to the symphysis menti and inferiorly by the body of the hyoid bone.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 25
Incorrect
-
A 37-year-old woman with a history of rheumatic heart disease presents with 10 days recurrent low fever. Patient underwent laboratory work up and was diagnosed with infective endocarditis. What is the most likely organism that caused the infective endocarditis in this patient?
Your Answer: Streptococcus pneumoniae
Correct Answer: Streptococcus viridans
Explanation:Subacute bacterial endocarditis is often due to streptococci of low virulence, mainly streptococcus viridans. It is a mild to moderate illness which progresses slowly over weeks and months (>2weeks) and has low propensity to hematogenously seed to extracardiac sites.
-
This question is part of the following fields:
- Microbiology
- Pathology
-
-
Question 26
Incorrect
-
A 40-year old lady with a flail chest due to trauma was breathing with the help of a mechanical ventilator in the ICU, and was heavily sedated on muscle relaxants. Due to sudden power failure, a nurse began to hand-ventilate the patient with a Ambu bag. What change will occur in the following parameters: (Arterial p(CO2), pH) in the intervening period between power failure and hand ventilation?
Your Answer: Decrease, Increase
Correct Answer: Increase, Decrease
Explanation:Respiratory acidosis occurs due to alveolar hypoventilation which leads to increased arterial carbon dioxide concentration (p(CO2)). This in turn decreases the HCO3 –/p(CO2) and decreases pH. Respiratory acidosis can be acute or chronic. In acute respiratory acidosis, the p(CO2) is raised above the upper limit of normal (over 45 mm Hg) with low pH. However, in chronic cases, the raised p(CO2) is accompanied with a normal or near-normal pH due to renal compensation and an increased serum bicarbonate (HCO3 – > 30 mmHg). The given problem represents acute respiratory acidosis and thus, will show a increase in arterial p(CO2) and decrease in pH.
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 27
Incorrect
-
Which of the following statements regarding aqueous humour is correct?
Your Answer: Is the only source of nutrients for the iris
Correct Answer: Is the only source of nutrients for the lens of the eye
Explanation:The aqueous humour is a transparent, watery fluid similar to plasma, but containing low protein concentrations. It is secreted from the ciliary epithelium and fills both the anterior and the posterior chambers of the eye. It maintains the intraocular pressure and inflates the globe of the eye. It is this hydrostatic pressure which keeps the eyeball in a roughly spherical shape and keeps the walls of the eyeball taut. It provides nutrition (e.g. amino acids and glucose) for the avascular ocular tissues; posterior cornea, trabecular meshwork, lens, and anterior vitreous. It may serve to transport ascorbate into the anterior segment to act as an antioxidant agent. The presence of immunoglobulins indicate its role in immune response to defend against pathogens.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 28
Incorrect
-
A 41 year old women presents with a history of carcinoma involving the right breast with enlarged axillary nodes on the same side. She underwent mastectomy and axillary node clearance. These were sent for histopathological examination. They showed no signs of metastasis. What could be cause of this enlargement in the lymph nodes?
Your Answer: Paracortical lymphoid hyperplasia
Correct Answer: Sinus histiocytosis
Explanation:Sinus histiocytosis also referred to as reticular hyperplasia, refers to the enlargement, distention and prominence of the sinusoids of the lymph nodes. This is a non-specific form of hyperplasia characteristically seen in lymph nodes that drain tumours. The endothelial lining of the lymph node becomes markedly hypertrophied, along with an increase in the number of macrophages which results in the distortion, distention and enlargement of the sinus. In this scenario there is no evidence that an infection or another malignancy could account for the enlargement. Paracortical lymphoid hyperplasia is caused by an immune response.
-
This question is part of the following fields:
- Inflammation & Immunology; Female Health
- Pathology
-
-
Question 29
Correct
-
Mallory bodies are characteristic of which of the following conditions?
Your Answer: Alcoholic hepatitis
Explanation:Mallory bodies (or ‘alcoholic hyaline’) are inclusion bodies in the cytoplasm of liver cells, seen in patients of alcoholic hepatitis; and also in Wilson’s disease. These pathological bodies are made of intermediate keratin filament proteins that are ubiquinated or bound by proteins like heat chock protein. Being highly eosinophilic, they appear pink on haematoxylin and eosin staining.
-
This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
-
-
Question 30
Incorrect
-
Which muscle originates from the common flexor tendon of the forearm?
Your Answer: Flexor digitorum profundus
Correct Answer: Flexor digitorum superficialis
Explanation:The medial epicondyle of the humerus is the site of origin of this group of muscles of the forearm. It originates from the medial epicondyle of the humerus by a common tendon. Fibres from the deep fascia of the forearm, near the elbow and septa, pass from this fascia between the muscles. These muscles include the pronator teres, palmaris longus, flexor carpi radialis, flexor carpi ulnaris and flexor digitorum superficialis.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 31
Correct
-
Which of these antibiotics is the first choice treatment for infections caused by Pseudomonas aeruginosa?
Your Answer: Piperacillin
Explanation:Piperacillin is an extended-spectrum beta-lactam antibiotic of the ureidopenicillin class. It is normally used with a beta-lactamase inhibitor such as tazobactam. The combination has activity against many Gram-positive and Gram-negative pathogens and anaerobes, including Pseudomonas aeruginosa. Piperacillin is sometimes referred to as an anti-pseudomonal penicillin.
-
This question is part of the following fields:
- Pathology
- Pharmacology
-
-
Question 32
Correct
-
A 78-year-old diabetic man undergoes renal function tests. Which of the following substances will be the most accurate for measuring glomerular filtration rate (GFR)?
Your Answer: Inulin
Explanation:Glomerular filtration rate (GFR) is the volume of fluid filtered from the renal glomerular capillaries into the Bowman’s capsule per unit time. Clinically, this is often measured to determine renal function. Inulin was originally used as it is not reabsorbed by the kidney after glomerular filtration, therefore its rate of excretion is directly proportional to the rate of filtration of water and solutes across the glomerular filter. However, in clinical practice, creatinine clearance is used to measure GFR. Creatinine is an endogenous molecule, synthesised in the body, that is freely filtered by the glomerulus (but also secreted by the renal tubules in very small amounts). Creatinine clearance exceeds GFR due to creatinine secretion, and is therefore a close approximation of the GFR.
-
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 33
Correct
-
The dura mater is a thick membrane that is the outermost of the three layers of the meninges. Which of the following foramen transmits the dura mater?
Your Answer: Foramen magnum
Explanation:The foramen magnum is found in the most inferior part of the posterior cranial fossa . It is traversed by vital structures including the medulla oblongata . Its contents include the following: medulla oblongata, meninges (arachnoid, dura and pia mater), spinal root of the accessory nerve, vertebral arteries, anterior and posterior spinal arteries, tectorial membrane and alar ligaments .
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 34
Correct
-
A 47-year old-woman diagnosed with pancreatitis presented to the emergency department complaining of a worsening shortness of breath, fever, agitation and cough. Oxygen saturation was 67% in room air. Her respiratory status continued to deteriorate therefore she was intubated. She was admitted to the intensive care unit for management. Chest X-ray demonstrated bilateral perihilar opacities. The patient failed conventional treatment and died several days later. At autopsy, the lung shows growth of type 2 pneumocytes and thickened alveolar walls. What is the most probable diagnosis?
Your Answer: Adult respiratory distress syndrome
Explanation:Acute (or adult) respiratory distress syndrome (ARDS) is a life-threatening lung condition characterised by a non-cardiogenic pulmonary oedema that leads to acute respiratory failure. The most common risk factors for ARDS include trauma with direct lung injury, sepsis, pneumonia, pancreatitis, burns, drug overdose, massive blood transfusion and shock. Acute onset of dyspnoea with hypoxemia, anxiety and agitation is typical. Chest X ray most commonly demonstrates bilateral pulmonary infiltrates. Histological changes include the exudative, proliferative and fibrotic phase. ARDS is mainly a clinical diagnosis.
-
This question is part of the following fields:
- Pathology
- Respiratory
-
-
Question 35
Incorrect
-
The posterior cord contains nerve fibres from which of the following levels of the spinal cord?
Your Answer: C5, C6 and C7
Correct Answer: C5, C6, C7, C8 and T1
Explanation:THE correct answer is A. The posterior cord derives its fibres from the spinal nerves C5,C6,C7,C8,T1. This cord is formed from the fusion of the posterior divisions of the upper, lower, and middle trunks.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 36
Incorrect
-
A 20 year lady is brought to the A&E following a road accident. She is hypotensive and a CT scan of the abdomen reveals a shattered spleen. An emergency splenectomy is performed where the splenic artery is ligated right at its origin. Which of the following arteries will have a diminished blood flow owing to ligation of the splenic artery at its origin?
Your Answer: Coeliac
Correct Answer: Left gastroepiploic
Explanation:Ligation of the splenic artery right at its point of origin should cut off blood flow in its branches. The following are the branches of the splenic artery: pancreatic branches, short gastric branches and left gastroepiploic arteries.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 37
Incorrect
-
what is the cause of a prolonged PT(prothrombin time)?
Your Answer: von Willebrand factor deficiency
Correct Answer: Liver disease
Explanation:PT measure the intrinsic pathway of coagulation. It determines the measure of the warfarin dose regime, liver disease and vit K deficiency status along with the clotting tendency of blood. PT measured factors are II,V,VII,X and fibrinogen. It is used along with aPTT which measure the intrinsic pathway.
-
This question is part of the following fields:
- General
- Physiology
-
-
Question 38
Correct
-
The majority of gallstones are mainly composed of:
Your Answer: Cholesterol
Explanation:Bile salts are formed out of cholesterol in the liver cells. Occasionally, precipitation of cholesterol occurs resulting into cholesterol stones developing in the gall bladder.
These cholesterol gallstones are the most common type and account for 80% of all gallstones. Another type, accounting for 20% gallstones is pigment stones which are composed of bilirubin and calcium salts. Occasionally, stones of mixed origin are also seen.
-
This question is part of the following fields:
- Gastroenterology
- Physiology
-
-
Question 39
Correct
-
Which lymph nodes are likely to be enlarged in a patient who has malignant growth involving the anus?
Your Answer: Superficial inguinal
Explanation:The lymphatics from the anus, skin of the perineum and the scrotum end in the superficial inguinal nodes. In case of a malignant growth of the anus, the superficial inguinal lymph nodes would most likely be enlarge.
-
This question is part of the following fields:
- Anatomy
- Pelvis
-
-
Question 40
Correct
-
Injury to which of the following arteries is likely to affect the blood supply to the seminal vesicles?
Your Answer: Middle rectal
Explanation:Ligation of middle rectal artery is most likely to affect the blood supply of seminal vesicles since arteries supplying the seminal vesicles are derived from the middle and inferior vesical and middle rectal arteries.
-
This question is part of the following fields:
- Anatomy
- Pelvis
-
-
Question 41
Correct
-
If a 55-year old gentleman who has suffered a stroke, develops a tremor in his fingers that worsens on reaching for an object, what part of his brain is likely to be involved?
Your Answer: Cerebellum
Explanation:The cerebellum plays an important role in the integration of sensory perception and motor output. Multiple neural pathways link the cerebellum with the motor cortex and the spinocerebellar tract. The cerebellum uses the constant feedback on body position to fine-tune the movements and integrates these pathways. The patient described here has a characteristic cerebellar tremor that is a slow, broad tremor of the extremities and occurs at the end of a purposeful movement.
-
This question is part of the following fields:
- Neurology
- Physiology
-
-
Question 42
Correct
-
A swimmer was struggling to finish his training following an injury to his right arm. On further examination it was found that any movements involving adduction, medial rotation and extension of her arm were particularly weak. Which nerve in this case was damaged?
Your Answer: Thoracodorsal
Explanation:Weakness on these particular movements indicate that there is a problem with the latissimus dorsi muscle. This muscle is very important particularly in swimming movements and is supplied by the thoracodorsal nerve.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 43
Incorrect
-
The uterine artery arises from the?
Your Answer: Abdominal aorta
Correct Answer: Internal iliac artery
Explanation:The uterine artery arises from the anterior division of the internal iliac artery and runs medially on the levator ani towards the uterine cervix.
-
This question is part of the following fields:
- Anatomy
- Pelvis
-
-
Question 44
Incorrect
-
A patient sustained an injury to the facial nerve after it emerges from the stylomastoid foramen. What is the clinical impact of this injury?
Your Answer: Taste from the anterior two-thirds of the tongue
Correct Answer: Facial expression
Explanation:The facial nerve is the seventh of the twelve paired cranial nerves. It emerges from the brainstem between the pons and the medulla. It controls the muscles of facial expression and supplies taste fibres to the anterior two-thirds of the tongue. It also supplies preganglionic parasympathetic fibres to several head and neck ganglia. Its branches and distribution are as follows:
Inside the facial canal (proximal to the stylomastoid foramen):
– Greater petrosal nerve – provides parasympathetic innervation to the lacrimal gland, as well as special taste sensory fibres to the palate via the nerve of pterygoid canal
– Nerve to stapedius – provides motor innervation for the stapedius muscle in the middle ear
– Chord tympani – provides parasympathetic innervation to the submandibular and sublingual glands and special sensory taste fibres for the anterior two-thirds of the tongue
Outside the skull (distal to the stylomastoid foramen):
– Posterior auricular nerve – controls the movements of some of the scalp muscles around the ear
– Five major facial branches (in the parotid gland), from top to bottom: temporal branch, zygomatic branch, buccal branch, marginal mandibular branch and cervical branch. From the description given above it is obvious that injury to the facial nerve distal to the stylomastoid foramen will affect facial expression.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 45
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
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 46
Incorrect
-
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: Ceftriaxone
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.
-
This question is part of the following fields:
- Microbiology
- Pathology
-
-
Question 47
Correct
-
An infant, 5 weeks and 6 days old born with a large sub-aortic ventricular septal defect, is prepared for pulmonary artery banding through a left thoracotomy (the child is not fit for a surgical closure). The surgeon initially passes his index finger immediately behind two great arteries in the pericardial sac to mobilise the great arteries in order to pass the tape around the pulmonary artery. Into which space is the surgeon's finger inserted?
Your Answer: Transverse pericardial sinus
Explanation:Cardiac notch: is an indentation on the left lung of the heart.
Coronary sinus: a venous sinus on the surface of the heart (the posterior aspect) that receives blood from the smaller veins that drain the heart.
Coronary sulcus: a groove on the heart between the atria and ventricles.
Transverse pericardial sinus: located behind the aorta and pulmonary trunk and anterior to the superior vena cava.
Oblique pericardial sinus: located behind the left atrium. Accessed from the inferior side (or the apex) of the heart upwards.
Horizontal pericardial sinus: this is a made-up term.
-
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 48
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.
-
This question is part of the following fields:
- Neoplasia
- Pathology
-
-
Question 49
Incorrect
-
Which of the following is likely to result in hematocolpos in a 12-year old girl?
Your Answer: Turner syndrome
Correct Answer: Imperforate hymen
Explanation:Hematocolpos means accumulation of blood in vagina and hematometra is accumulation of blood in the uterus. These are most likely seen with an imperforate hymen; which is seen I 1 in 2000 females. If spontaneous resolution does not occur, treatment involves making a hole in the hymen to allow discharge of menstrual blood.
-
This question is part of the following fields:
- Pathology
- Women's Health
-
-
Question 50
Correct
-
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: 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
-
This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
-
-
Question 51
Correct
-
A 30 year old man suffered severe blood loss, approx. 20-30% of his blood volume. What changes are most likely seen in the pulmonary vascular resistance (PVR) and pulmonary artery pressure (PAP) respectively following this decrease in cardiac output?
Your Answer: Increase Decrease
Explanation:Hypovolemia will result in the activation of the sympathetic adrenal discharge resulting is a decrease pulmonary artery pressure and an elevated pulmonary vascular resistance.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 52
Correct
-
A 35-year-old ultra marathon runner becomes severely dehydrated and collapses. This patient most likely has:
Your 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.
-
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 53
Correct
-
A patient who underwent emergency appendicectomy complains of having numbness (paraesthesia) of the skin at the pubic region. Which nerve was most likely injured in the operation?
Your Answer: Iliohypogastric
Explanation:The iliohypogastric nerve comes from L1 and emerges from the upper part of the lateral border of the psoas major. It then crosses obliquely in front of the quadratus lumborum to the iliac crest where it perforates the posterior part of transversus abdominis and divides between that muscle and the internal oblique into a lateral and an anterior cutaneous branch. This provides sensory innervation to the skin of the lower abdominal wall, upper hip and upper thigh.
The genitofemoral nerve also comes from the lumbar plexus that innervates the skin of the anterior scrotum or labia majora and upper medial thigh.
The subcostal nerve is the ventral primary ramus of T12 providing sensory innervation to the anterolateral abdominal wall in an area superior to the pubic region.
A spinal nerve owing to their deep location would not have been injured in the procedure.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 54
Incorrect
-
Both the arytenoid muscles and the lateral cricoarytenoid muscles perform this action on the glottis:
Your Answer: Abduction
Correct Answer: Adduction
Explanation:Both the arytenoid and the cricoartenoid muscles close the glottis. The lateral cricoarytenoid muscles extend from the lateral cricoid cartilage to the muscular process of the arytenoid cartilage. By rotating the arytenoid cartilages medially, these muscles adduct the vocal cords and thereby close the rima glottidis. The arytenoid muscle adducts or approximates the arytenoid cartilages, and thus closes the aperture of the glottis.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 55
Incorrect
-
An electronic manufacturing engineer had abdominal distension and underwent a CT scan of the abdomen. Thereafter he was diagnosed with hepatic angiosarcoma. Exposure to what agent is responsible for the development of this neoplasm?
Your Answer: Aflatoxin
Correct Answer: Arsenic
Explanation:Hepatic angiosarcomas are associated with particular carcinogens which includes: arsenic , thorotrast, and polyvinyl chloride. With exposure to this three agents, there is a very long latent period of many years between exposure and the development of tumours.
-
This question is part of the following fields:
- Neoplasia
- Pathology
-
-
Question 56
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.
-
This question is part of the following fields:
- Pathology
- Respiratory
-
-
Question 57
Correct
-
In a young, sexually active male, what is the most common cause of non-gonococcal urethritis?
Your Answer: Chlamydia
Explanation:Non-gonococcal urethritis is most commonly caused by Chlamydia trachomatis (50% cases). Less common organisms include Mycoplasma genitalium, Urea urealyticum and Trichomonas vaginalis. Chlamydia is also the commonest cause of non-gonococcal cervicitis in women and proctitis in both sexes.
-
This question is part of the following fields:
- Pathology
- Renal
-
-
Question 58
Incorrect
-
A patient with Paget's disease of the bone is predisposed to developing which type of cancer?
Your Answer: Metastatic duct carcinoma of the breast
Correct Answer: Osteosarcoma
Explanation:Paget’s disease of bone (PDB) is a focal disorder of bone. It is presumed benign in nature and mediated by abnormal osteoclast function. However osteosarcomas may occur in <1% of patients with Paget's disease of the bone. Osteosarcomas are osteogenic in origin, and consistently arise in sites of pagetic bone. This is not to be confused with Paget's disease of the breast.
-
This question is part of the following fields:
- Neoplasia
- Pathology
-
-
Question 59
Correct
-
In an anatomy demonstration, the instructor asked one of the medical students to pass his index finger inferior to the root of the left lung. The student notices that his finger is blocked by a structure. Which structure do you think is responsible for this?
Your Answer: Pulmonary ligament
Explanation:The pulmonary ligament is dual layer of pleura stretching from the inferior part of the hilar reflection toward the diaphragm.
The costodiaphragmatic recess is the cavity at the inferior border of the lung where the costal pleura becomes the diaphragmatic pleura.
The cupola: is part of the pleura that extends superiorly above the first rib and has no association with the root of the lung.
Inferior vena cava is located in the mediastinum, not near the root of the lung.
Left pulmonary veins being part of the root of the lung, would not block access to behind the lung. Costomediastinal recess is the part of the pleura where the costal pleura become the mediastinal pleura.
-
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 60
Incorrect
-
Which of these nerves controls adduction of hand?
Your Answer: Upper subscapular nerve
Correct Answer: Ulnar nerve
Explanation:The adductors of the fingers are the palmer interossei. They are supplied by the ulnar nerve, which is a branch of the medical cord of the brachial plexus.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 61
Correct
-
After being admitted to the hospital, a 60-year-old man is administered sodium nitroprusside. Which class of drugs does nitroprusside belong to?
Your Answer: Vasodilators
Explanation:Sodium nitroprusside is a potent peripheral vasodilator that affects both arterioles and venules. It is often administered intravenously to patients who are experiencing a hypertensive emergency. It reduces both total peripheral resistance as well as venous return, so decreasing both preload and afterload. For this reason it can be used in severe cardiogenic heart failure where this combination of effects can act to increase cardiac output. It is administered by intravenous infusion. Onset is typically immediate and effects last for up to ten minutes. The duration of treatment should not exceed 72 hours.
-
This question is part of the following fields:
- Pathology
- Pharmacology
-
-
Question 62
Incorrect
-
Carbon dioxide is principally transported in the blood in which form?
Your Answer: CO2 physically dissolved in solution
Correct Answer: Bicarbonate
Explanation:Carbon dioxide is transported in the blood in various forms:
– Bicarbonate (80–90%)
– Carbamino compounds (5–10%)
– Physically dissolved in solution (5%).
Carbon dioxide is carried on the haemoglobin molecule as carbamino-haemoglobin; carboxyhaemoglobin is the combination of haemoglobin with carbon monoxide.
-
This question is part of the following fields:
- Physiology
- Respiratory; Cardiovascular
-
-
Question 63
Incorrect
-
What causes a reduction in pulmonary functional residual capacity?
Your Answer: Emphysema
Correct Answer: Pulmonary fibrosis
Explanation:Pulmonary functional residual capacity (FRC) is = volume of air present in the lungs at the end of passive expiration.
Obstructive diseases (e.g. emphysema, chronic bronchitis, asthma) = an increase in FRC due to an increase in lung compliance and air trapping.
Restrictive diseases (e.g. pulmonary fibrosis) result in stiffer, less compliant lungs and a reduction in FRC.
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 64
Incorrect
-
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: IIB
Correct 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).
-
This question is part of the following fields:
- Neoplasia
- Pathology
-
-
Question 65
Correct
-
The specimen sent to the pathologist for examination was found to be benign. Which one of the following is most likely a benign tumour?
Your Answer: Warthin’s tumour
Explanation:Warthin’s tumour is also known as papillary cystadenoma lymphomatosum. It is a benign cystic tumour of the salivary glands containing abundant lymphocytes and germinal centres. It has a slightly higher incidence in males and most likely occur in older adults aged between 60 to 70 years. This tumour is also associated with smoking. Smokers have an eight-fold greater risk in developing the tumour compared to non-smokers.
-
This question is part of the following fields:
- Neoplasia
- Pathology
-
-
Question 66
Correct
-
The stomach is an organ that is divided into several important anatomical parts. These parts of the stomach have varied arterial blood supply that ensure that the whole organ receive oxygenated blood. Which of the following arteries if ligated, will not render any portion of the stomach ischaemic?
Your Answer: Superior mesenteric
Explanation:The blood supply to the stomach is through the following arteries:
– The superior mesenteric artery supplies blood to the lower part of the duodenum, pancreas and two-thirds of the transverse colon. Thus ligation of the superior mesenteric artery would not affect the stomach.
– The right and the left gastroepiploic arteries supply the greater curvature of the stomach – along its edges.
– The short gastric artery supplies blood to the upper portion of the of the greater curvature and the fundus of the stomach.
– The gastroduodenal artery supplies blood to the distal part of the stomach (the pyloric sphincter) and the proximal end of the duodenum.
– The left gastroepiploic and the short gastric are branches of the splenic artery and therefore ligation of the splenic artery would directly affect the stomach.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 67
Incorrect
-
Calculate the total peripheral resistance for a patient with a blood pressure of 130/70 mm HG and cardiac output of 5 litres / min?
Your Answer: 22 mmHg × min/l
Correct Answer: 18 mmHg × min/l
Explanation:Total peripheral resistance = Mean arterial pressure/Cardiac output. And the mean arterial pressure = Diastolic pressure + 1/3 (Systolic pressure – Diastolic pressure), i.e., 70 + 1/3 (130-70) = 90 mmHg. Therefore, total peripheral resistance = 90 mmHg/5 l per min = 18 mmHg × min/l.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 68
Incorrect
-
Which of the following morphological characteristic is a salient feature of a pure apoptotic cell?
Your Answer: Cellular swelling
Correct 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.
-
This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
-
-
Question 69
Correct
-
A 65-year old gentleman presents to the clinic with chronic back pain and weight loss. His blood count shows a white blood cell count of 10 × 109/l, with a differential count of 66 polymorphonuclear leukocytes, 7 bands, 3 metamyelocytes, 3 myelocytes, 14 lymphocytes, 7 monocytes, and 5 nucleated red blood cells. The haemoglobin is 13 g/dl with a haematocrit of 38.1%, a mean corpuscular volume of 82 fl, and a platelet count of 126 × 109/l. What is the likely diagnosis?
Your Answer: Metastatic carcinoma
Explanation:The peripheral blood findings suggest a leucoerythroblastic picture, the common causes of which in a 65-year old gentleman includes prostatic or lung malignancy.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 70
Correct
-
After a prolonged coronary artery bypass surgery, a 60-year old gentleman was transfused 3 units of fresh-frozen plasma and 2 units of packed red cells. Two days later, the nurse noticed that he was tachypnoeic and chest X-ray showed signs consistent with adult respiratory distress syndrome. Which of the following variables will be low in this patient?
Your Answer: Compliance of the lung
Explanation:Acute or adult respiratory distress syndrome (ARDS) is a reaction to several forms of lung injuries and is commonly associated with sepsis and SIRS (systemic inflammatory response syndrome), severe traumatic injury, severe head injury, narcotics overdose, drowning, pulmonary contusion, and multiple blood transfusions. There is an increase in risk due to pre-existing liver disease or coagulation abnormalities. It results due to indirect toxic effects of neutrophil-derived inflammatory mediators in the lungs. ARDS is defined by the 1994 American–European Consensus Committee as the acute onset of bilateral infiltrates on chest X-ray, a partial pressure of arterial oxygen (pa(O2)) to fraction of inspired oxygen Fi(O2) ratio of less than 200 mmHg and a pulmonary artery occlusion pressure of less than 18 or the absence of clinical evidence of left arterial hypertension. ARDS is basically pulmonary oedema in the absence of volume overload or poor left ventricular function. This is different from acute lung injury, which shows a pa(O2)/Fi(O2) ratio of less than 300 mmHg. Pathogenesis of ARDS starts from damage to alveolar epithelium and vascular endothelium, causing increased permeability. Damage to surfactant-producing type II cells disrupts the production and function of pulmonary surfactant, causing micro atelectasis and poor gas exchange. There is a decrease in lung compliance and increase in work of breathing. Eventually, there is resorption of alveolar oedema, regeneration of epithelial cells, proliferation and differentiation of type II alveolar cells and alveolar remodelling. Some show resolution and some progress to fibrosing alveolitis, which involves the deposition of collagen in alveolar, vascular and interstitial spaces.
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 71
Correct
-
The pleural cavity is the space between the two pulmonary pleurae which cover the lungs. What is the normal amount of pleural fluid?
Your Answer: 10 ml
Explanation:Pleural fluid is a serous fluid produced by the serous membrane covering normal pleurae. Most fluid is produced by the parietal circulation (intercostal arteries) via bulk flow and reabsorbed by the lymphatic system. The total volume of fluid present in the intrapleural space is estimated to be only 2–10 ml. A small amount of protein is present in intrapleural fluid. Normally, the rate of reabsorption increases as a physiological response to accumulating fluid.
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 72
Correct
-
Two boys were playing when one of them brought the forearm of the other behind his back. This resulted in a stretching of the lateral rotator of the arm. Which of the following muscles was most likely to have been involved?
Your Answer: Infraspinatus
Explanation:There are two lateral rotators of the arm, the infraspinatus and the teres minor muscles. The infraspinatus muscle receives nerve supply from C5 and C6 via the suprascapular nerve, whilst the teres minor is supplied by C5 via the axillary nerve.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 73
Correct
-
What percentage of the cardiac output is delivered to the brain?
Your Answer: 15%
Explanation:Among all body organs, the brain is most susceptible to ischaemia. Comprising of only 2.5% of total body weight, the brain receives 15% of the cardiac output. Oxygen extraction is also higher with venous oxygen levels approximating 13 vol%, and arteriovenous oxygen difference of 7 vol%.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 74
Correct
-
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.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 75
Incorrect
-
During hysterectomy, the ureter is most likely to be ligated when a surgeon is clamping the?
Your Answer: Ovarian ligaments
Correct Answer: Uterine arteries
Explanation:The ureter forms the posterior boundary of a shallow depression which lodges the ovary and then runs medially and forward on the lateral aspect of the uterine cervix and upper part of the vagina to reach the fundus of the bladder. It is also situated about 2cm from the side of the cervix of the uterus. The relationship of the ureters and uterine arteries is of clinical significance because the arteries are at risk of iatrogenic injury during hysterectomy.
-
This question is part of the following fields:
- Anatomy
- Pelvis
-
-
Question 76
Correct
-
Depression of the normal coagulation system and excessive bleeding after surgery can occur in which of the following medical conditions?
Your Answer: Liver disease
Explanation:As most of the coagulation factors are synthesized in the liver, liver diseases like hepatitis or cirrhosis will depress the coagulation system. Vitamin K deficiency can also decrease the production of vitamin K dependent coagulation factors VII, XI, X and prothrombin.
-
This question is part of the following fields:
- General
- Physiology
-
-
Question 77
Correct
-
Which of the following terms best describes the movement of leukocytes towards a specific target?
Your Answer: Chemotaxis
Explanation:The movement of leukocytes towards a chemical mediator is termed chemotaxis and the mediators likewise called chemoattractants.
Diapedesis is the squeezing of the leukocytes from the capillary wall into the intercellular space.
Endocytosis is engulfing of a small substance by the cells e.g. glucose, protein, fats.
Margination is lining of the WBC along the periphery of the blood vessel.
Adhesion is attachment with the vessel wall.
Phagocytosis is described as engulfing the bacteria or the offending substance.
-
This question is part of the following fields:
- Inflammation & Immunology
- Pathology
-
-
Question 78
Incorrect
-
A 40 year old patient with an history of obesity has been diagnosed with meralgia parasthetica. The condition was discovered to be caused by the pinching of the lateral femoral cutaneous nerve. Injuries at what spinal levels usually affect this nerve?
Your Answer: L1, L2
Correct Answer: L2, L3
Explanation:The lateral femoral cutaneous nerve of the thigh arises from the dorsal division of the lumbar plexus of the second and the third lumbar nerves (L2 – L3). Spinal injuries at this level are likely to affect the lateral femoral cutaneous nerve. The lateral femoral cutaneous nerve innervates the skin on the lateral aspect of the thigh.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 79
Incorrect
-
Question 80
Correct
-
Which part of the nephron would have to be damaged to stop the reabsorption of the majority of salt and water?
Your Answer: Proximal tubule
Explanation:The proximal tubule is the portion of the duct system of the nephron of the kidney which leads from Bowman’s capsule to the loop of Henle. It is conventionally divided into the proximal convoluted tubule (PCT) and the proximal straight tubule (PST). The proximal tubule reabsorbs the majority (about two-thirds) of filtered salt and water. This is done in an essentially iso-osmotic manner. Both the luminal salt concentration and the luminal osmolality remain constant (and equal to plasma values) along the entire length of the proximal tubule. Water and salt are reabsorbed proportionally because the water is dependent on and coupled with the active reabsorption of Na+. The water permeability of the proximal tubule is high and therefore a significant transepithelial osmotic gradient is not possible.
-
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 81
Correct
-
The muscles of the superficial posterior compartment of the leg insert into the:
Your Answer: Calcaneus
Explanation:The muscles of the superficial posterior compartment of the leg form the characteristic ‘calf’ shape of the posterior leg and include the gastrocnemius, soleus and plantaris. The gastrocnemius and soleus together form a muscular mass which is occasionally described as the triceps surae; its tendon of insertion is the tendo calcaneus. The tendo calcaneus is the thickest and strongest in the body and together with the tendon of the plantaris muscle is inserted into the posterior part of the calcaneus.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 82
Incorrect
-
A 7-year-old boy is diagnosed with metabolic acidosis as a result of severe dehydration. Which of the following conditions is most likely to cause severe dehydration and metabolic acidosis?
Your Answer: Severe persistent vomiting
Correct Answer: Severe diarrhoea
Explanation:Diarrhoea is defined as having three or more loose or liquid stools per day, or as having more stools than is normal for that person. Severe diarrhoea, causing fluid loss and loss of bicarbonate, will result in marked dehydration and metabolic acidosis.
-
This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
-
-
Question 83
Correct
-
A 39-year old female patient was diagnosed with a tumour of the left adrenal gland. The tumour, which is metastasizing to the adjacent tissues, has already extended to the left suprarenal vein. If the tumour is still spreading, which of the following veins will most likely be affected after the involvement of the left suprarenal vein?
Your Answer: Left renal vein
Explanation:The suprarenal veins or also known as the veins of Warshaw, are the veins that receive blood from the suprarenal glands. These veins receive blood from the medullary venous plexus and the cortex of the adrenal glands (suprarenal glands). They are two in number – the left and the right suprarenal veins. The right suprarenal vein drains into the inferior vena cava while the left suprarenal vein drains into the left renal vein. This therefore means that in the case of a metastasizing tumour involving the left suprarenal vein, the tumour will most likely extend from the left suprarenal vein to the left renal vein into which it drains.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 84
Incorrect
-
Regarding the posterior compartment of the leg, which is correct?
Your Answer: The muscles dorsiflex the foot and are innervated by the deep fibular nerve
Correct Answer: The muscles plantarflex the foot and are innervated by the tibial nerve
Explanation:The muscles of the back of the leg are subdivided into two groups: superficial and deep. Superficial muscles include gastrocnemius, soleus and plantaris. Deep muscles include tibialis posterior, flexor hallucis longus, flexor digitorum longus and popliteus. The superficial ( calf muscles) which are responsible for plantarflexion of the foot are supplied by the tibial nerve as follows: the gastrocnemius and soleus muscles are supplied by the first and second sacral nerves and the plantaris by the fourth and fifth lumbar and first sacral nerve (the tibial nerve).
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 85
Correct
-
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.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 86
Correct
-
Which of the following arteries is the posterior branch of the external carotid artery?
Your Answer: Superficial temporal
Explanation:The external carotid artery is a branch of the common carotid artery that supplies parts of the neck, head and face. It branches off from the common carotid artery at the level of the thyroid cartilage. The external carotid, at the level of the mandible divides into the maxillary artery and the superficial temporal. The superficial temporal artery is the posterior branch of these two arteries. It starts off, somewhat, as a continuation of the external carotid artery at the substance of the parotid gland. Anterior cerebral and middle cerebral arteries are branches of the internal carotid artery.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 87
Incorrect
-
This structure divides the space between the lens and the cornea into the anterior and posterior chambers of the eye:
Your Answer: The lens
Correct Answer: The iris
Explanation:The iris divides the space between the lens and the cornea into an anterior and a posterior chamber. The anterior cavity is filled with watery aqueous fluid, and the posterior cavity with a gel-like vitreous fluid. The anterior chamber of the eye is bounded in front by the posterior surface of the cornea; behind by the front of the iris and the central part of the lens. The posterior chamber is a narrow gap behind the peripheral part of the iris and in front of the suspensory ligament of the lens and the ciliary processes.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 88
Incorrect
-
A diabetic 58-year-old man, after the injection of radiographic contrast, has a decreased urine output and decreased level of consciousness. Which of the following conditions has he most likely developed
Your Answer: Acute interstitial nephritis
Correct Answer: Acute tubular necrosis
Explanation:Acute tubular necrosis (ATN) involves damage to the tubule cells of the kidneys and is the most common cause of acute kidney injury. ATN in the majority of the cases is caused by ischaemia of the kidneys due to lack of perfusion and oxygenation but it may also occur due to poison or harmful substance. Contrast used for radiology may cause ATN in patients with several risk factors e.g. diabetic nephropathy. Symptoms may include oliguria, nausea, fluid retention, fatigue and decreased consciousness.
-
This question is part of the following fields:
- Pathology
- Renal
-
-
Question 89
Incorrect
-
A 25 year old women is pregnant with her second child. She is A- blood group. Her first child was Rh+ and the father is also Rh+. The second child is at a risk of developing which condition?
Your Answer: ABO incompatibility
Correct Answer: Haemolytic disease of the new-born
Explanation:This infant is at risk for haemolytic disease of the new born also known as erythroblastosis fetalis. In the pregnancy, Rh-positive RBC’s cross the placenta and enter the mothers blood system. She then becomes sensitised and forms IgG antibodies/anti-Rh antibodies against them. The second child is at a greater risk for this disease than the first child with Rh-positive blood group as during the second pregnancy, a more powerful response is produced. IgG has the ability to cross the placenta and bind to the fetal RBCs (type II hypersensitivity reaction) which are phagocytosed by the macrophages.
-
This question is part of the following fields:
- Inflammation & Immunology; Haematology
- Pathology
-
-
Question 90
Correct
-
Which of the following key features will be seen in an organ undergoing atrophy?
Your Answer: A greater number of autophagic vacuoles
Explanation:Atrophy is characterised by the breakdown of intracellular components along with organelles and packing them into vacuoles known as autophagic vacuoles. This is an adaptive response that separates the damaged cellular structures from the rest of the cells.
-
This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
-
-
Question 91
Incorrect
-
The muscle that depresses the glenoid fossa directly is the:
Your Answer: Supraspinatus
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.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 92
Incorrect
-
An 8 year old boy presents with a history of repeated bacterial/pyogenic infections. He had a normal recovery from chickenpox and measles and shows normal antibody response. A decrease in which of the cell types can best explain this history of repeated pyogenic infections?
Your Answer: B lymphocytes
Correct Answer: Neutrophils
Explanation:A decrease in the number of granulocytes, particularly neutrophils is known as agranulocytosis and it increases the susceptibility of an individual towards recurrent infections. Neutropenia can be either due to decreased production or increased elimination of neutrophils.
Ineffective agranulopoiesis is seen in: 1. myeloid stem cell suppression, 2. disease conditions associated with granulopoiesis such as megaloblastic anaemia and myelodysplastic syndromes, 3. rare genetic diseases, 4. splenic sequestration and 5. increased peripheral utilization.
-
This question is part of the following fields:
- Inflammation & Immunology
- Pathology
-
-
Question 93
Correct
-
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.
-
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 94
Incorrect
-
A 73-year-old woman goes to the doctor complaining of pain and stiffness in her shoulders and hips for 4 months, which is worst in the mornings. She has also been suffering from fatigue, weight loss and depression. There were no abnormal findings on physical examination. The erythrocyte sedimentation rate was 110 mm/hour, and serum rheumatoid factor and antinuclear antibody assays were negative. Mild normochromic normocytic anaemia was also found. What is the most likely diagnosis in this case?
Your Answer: Osteoarthritis
Correct Answer: Polymyalgia rheumatica
Explanation:Polymyalgia rheumatica (PMR) affects older adults, with an acute or subacute onset. Symptoms include severe pain and stiffness of the neck and pectoral or pelvic girdles, which is worse in the morning or after a period of inactivity and is usually bilateral. Other symptoms can include fatigue, weight loss, depression and fever. The erythrocyte sedimentation rate is usually elevated, and normochromic normocytic anaemia can occur. Other tests are usually normal in this disease.
-
This question is part of the following fields:
- Orthopaedics
- Pathology
-
-
Question 95
Correct
-
A space defined by the teres major muscle, the teres minor muscle, long head of the triceps brachii muscle and surgical neck of the humerus contains the axillary nerve and the?
Your Answer: Posterior circumflex humeral artery
Explanation:This quadrangular space transmits the posterior circumflex humeral vessels and the axillary nerve.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 96
Incorrect
-
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: Lateral femoral circumflex artery
Correct Answer: Obturator artery
Explanation:The posterior branch of the obturator artery provides an articular branch to the head of the femur.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 97
Incorrect
-
Which of the following conditions of the breast is most often associated with use of oral contraceptives?
Your Answer: Hypertrophy
Correct Answer: Cyst formation
Explanation:Breast cysts are common and are smooth, firm, mobile lumps that can sometimes be tender. Cysts can also be bilateral and are known to recur in 10% of cases. They are more common in women in the third and fourth decades and most often disappear after menopause. Cysts are filled with fluid from the breast which occurs due to the normal menstrual cycle of a woman. The end of the menstrual cycle causes breast cells to swell. After the menses, the cells shrink and the released fluid disappears. However, in some cases this fluid forms a cyst. Incidence of cysts was also linked to use of oral contraceptives.
-
This question is part of the following fields:
- Pathology
- Women's Health
-
-
Question 98
Incorrect
-
In which of the following conditions will the oxygen-haemoglobin dissociation curve shift to the right?
Your Answer: Decrease in temperature
Correct Answer: Exercise
Explanation:The oxygen-haemoglobin dissociation curve plots saturated haemoglobin against the oxygen tension and is usually a sigmoid plot. Each molecule of haemoglobin can bind to four molecules of oxygen reversibly. Factors that can influence the binding include: pH, concentration of 2,3-diphosphoglycerate (2,3-DPG), temperature, type of haemoglobin molecules, and presence of toxins, especially carbon monoxide. Shape of the curve is due to interaction of bound oxygen molecules with the incoming molecules. The binding of first molecule is difficult, with easier binding of the second and third molecule and increase in difficulty with the fourth molecule – partly as a result of crowding and partly as a natural tendency of oxygen to dissociate.
Left shift of curve indicates haemoglobin’s increased affinity for oxygen (seen at lungs). Right shift indicates decreased affinity and is seen with an increase in body temperature, hydrogen ions, 2,3-diphosphoglycerate (DPG), carbon dioxide concentration and exercise. Under normal resting conditions in a healthy individual, the normal position of the curve is at a pH of 7.4. A shift in the position of the curve with a change in pH is called the Bohr effect. Left shift occurs in acute alkalosis, decrease in p(CO2), decrease in temperature and decrease in 2,3-DPG. The fetal haemoglobin curve is to the left of the adult haemoglobin to allow for oxygen diffusion across the placenta. The curve for myoglobin is even further to the left. Carbon monoxide has a much higher affinity for haemoglobin than oxygen does. Thus, carbon monoxide poisoning leads to hypoxia.
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 99
Incorrect
-
Which type of contractions are responsible for the propulsion of chyme along the small intestine?
Your Answer: Peristaltic waves
Correct Answer: Segmentation
Explanation:Two major types of intestinal contractions are segmentation and peristalsis:
Segmentation occurs most frequently and primarily involves circular muscle. It is essentially a contraction of 2- or 3-cm long intestinal segments while the muscle on either side of it relaxes. Chyme in the segment is displaced in both directions. As the contracted segment relaxes, the previously relaxed segments on either side may contract. This efficiently mixes the chyme with the digestive secretions and exposes the mucosal absorptive surface to the luminal contents. It also serves a propulsive function and contributes to the movement of chyme.
Peristalsis is a propulsive wave of contraction that is initiated by intestinal distension. It is short lived and travels only a few centimetres before dying out. The combined effects of intestinal peristalsis and segmentation provide for both adequate mixing of the intestinal contents and slow, steady movement of chyme.
-
This question is part of the following fields:
- Gastroenterology
- Physiology
-
-
Question 100
Correct
-
Pseudomonas aeruginosa is a multidrug resistant pathogen that causes hospital-acquired infections. It is usually treated with piperacillin or another antibiotic. Which of the following is the other antibiotic?
Your Answer: Azlocillin
Explanation:Azlocillin, like piperacillin, is an acylampicillin antibiotic with an extended spectrum of activity and greater in vitro potency than the carboxypenicillins. Azlocillin is similar to mezlocillin and piperacillin. It demonstrates antibacterial activity against a broad spectrum of bacteria, including Pseudomonas aeruginosa.
-
This question is part of the following fields:
- Pathology
- Pharmacology
-
SESSION STATS - PERFORMANCE PER SPECIALTY
