-
Question 1
Correct
-
A computer tomography guided needle biopsy is done on a patient with a cystic swelling in the left chest. The radiologist inserted the biopsy needle into the 9th intercostal space along the mid axillary line to aspirate the swelling and obtain tissue for histological diagnosis. In which space is the swelling most likely to be?
Your Answer: Costodiaphragmatic recess
Explanation:The costodiaphragmatic recess is the lowest point of the pleural sac where the costal pleura becomes the diaphragmatic pleura. At the midclavicular line, this is found between ribs 6 and 8; at the paravertebral lines, between ribs 10 and 12 and between ribs 8 and 10 at the midaxillary line.
The cardiac notch: is an indentation of the heart on the left lung, located on the anterior surface of the lung.
Cupola: part of the parietal pleura that extends above the first rib.
Oblique pericardial sinus: part of the pericardial sac located posterior to the heart behind the left atrium.
Costomediastinal recess: a reflection of the pleura from the costal surface to the mediastinal surface, is on the anterior surface of the chest.
The inferior mediastinum: is the space in the chest occupied by the heart.
-
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 2
Correct
-
Paracentesis of ascetic fluid in a 45-year old woman revealed the following : clear, yellow fluid with protein 2.0 g/dl and a few mesothelial and mononuclear cells seen. No malignant cells seen. What is the likely diagnosis?
Your Answer: Cirrhosis
Explanation:Ascites develops either from:
-
- Increased accumulation
- Increased capillary permeability
- Increased venous pressure
- Decreased protein (oncotic pressure)
- Decreased clearance
- Increased lymphatic obstruction
- Increased accumulation
Cause
- Transudate (<30g/L protein) (Systemic disease)
- Liver (Cirrhosis)
- Cardiac e.g. RHF, CCF, SBE right heart valve disease and constrictive Pericarditis
- Renal failure
- Hypoalbuminaemia (nephrosis)
- Exudate (>30g/L protein) (Local disease)
- Malignancy
- Venous obstruction e.g. Budd-Chiari, Schistosomiasis
- Pancreatitis
- Lymphatic obstruction
- Infection (especially TB)
Cirrhosis is disease of the liver that is characterized by fibrosis leading to disorganization of the hepatic architecture. It shows the development of regenerative nodules surrounded by dense fibrotic tissue. Cirrhosis shows non-specific symptoms initially, which include fatigue, anorexia and weight loss. It can later progress to portal hypertension, ascites and liver failure.
-
-
This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
-
-
Question 3
Correct
-
A patient at the time of her second delivery opted for a bilateral pudendal nerve block. In order to inject the anaesthetic agent near the pudendal nerve a anaesthetic consultant had to insert a finger into the vagina and press laterally to palpate which landmark?
Your Answer: Ischial spine
Explanation:The ischial spine is always palpated through the walls of the vagina when performing a transvaginal pudendal nerve block and can easily be palpated on the lateral wall of the vagina.
-
This question is part of the following fields:
- Anatomy
- Pelvis
-
-
Question 4
Incorrect
-
Which of these substances is secreted by pericytes in the juxtaglomerular cells?
Your Answer: Erythropoietin
Correct Answer: Renin
Explanation:The juxtaglomerular cells synthesise, store and secrete the enzyme renin in the kidney. They are specialised smooth muscle cells in the wall of the afferent arteriole that delivers blood to the glomerulus and thus play a critical role in the renin– angiotensin system and so in renal autoregulation.
-
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 5
Incorrect
-
During cardiac catheterisation in a 20-year old man, the following data is obtained: Pressure (mmHg), O2 saturation (%) Right atrium 7 (N = 5) 90 (N = 75), Right ventricle 35/7 (N = 25/5) 90 (N = 75), Pulmonary artery 35/8 (N = 25/15), 90 (N = 75), Left atrium 7 (N = 9) 95 (N = 95), Left ventricle 110/7 (N = 110/9) 95 (N = 95), Aorta 110/75 (N = 110/75) 95 (N = 95) where N = Normal value. What is the likely diagnosis?
Your Answer: Tricuspid insufficiency
Correct Answer: Atrial septal defect
Explanation:A congenital heart disease, ASD or atrial septal defect leads to a communication between the right and left atria due to a defect in the interatrial septum. This leads to mixing of arterial and venous blood from the right and left side of the heart. The hemodynamic significance of this defect depends on the presence of shunting of blood. Normally, the left side of the heart has higher pressure than the right as the left side has to pump blood throughout the body. A large ASD (> 9 mm) will result in a clinically significant left-to-right shunt, causing volume overload of the right atrium and ventricle, eventually leading to heart failure. Cardiac catheterization would reveal very high oxygen saturation in the right atrium, right ventricle and pulmonary artery. Eventually, the left-to-right shunt will lead to pulmonary hypertension and increased afterload in the right ventricle, along with the increased preload due to the shunted blood. This will either cause right ventricular failure, or raise the pressure in the right side of the heart to equal or more than that in the left. Elevation of right atrial pressure to that of left atrial pressure would thus lead to diminishing or complete cessation of the shunt. If left uncorrected, there will be reversal of the shunt, known as Eisenmenger syndrome, resulting in clinical signs of cyanosis as the oxygen-poor blood form right side of the heart will mix with the blood in left side and reach the peripheral vascular system.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 6
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 7
Correct
-
A 45 year old women has a 4 cm non tender mass in her right breast which is fixed to the chest wall. Another 2cm non-tender mass is palpable in the left axilla. Chest x ray reveals multiple nodules ranging from 0.5 - 0.2 cm in both the lungs. What is the stage of her disease?
Your Answer: T4 N1 M1
Explanation:This woman has an invasive primary tumour mass with axillary node and lung metastases, making this stage T4 N1 M1. Looking at the other stems, T1 N1 M0 signifies a small primary cancer with nodal metastases but no distant metastases; T1 N0 M1 signifies a small primary cancer with no lymph node metastases but with distant metastases; T2 N1 M0 signifies a larger primary cancer with nodal metastases but no distant metastases; and T3 N0 M0 indicates a larger primary cancer with no metastases to either lymph nodes or to distant sites.
-
This question is part of the following fields:
- Neoplasia; Female Health
- Pathology
-
-
Question 8
Correct
-
What is the most likely cause of bitemporal hemianopia?
Your Answer: Prolactinoma
Explanation:Prolactinoma is the mot common pituitary adenoma; leading to hyperprolactinaemia. By virtue of their size, macroprolactinomas press on the adjacent structures leading to headaches and loss of vision due to the pressure effect on optic chiasm. Women notice a change in their menstrual cycle due to raised prolactin levels. In comparison, the problem goes unnoticed in men in the initial stages. Craniopharyngioma is a less common space-occupying lesions affecting children and young adults.
-
This question is part of the following fields:
- Endocrine
- Pathology
-
-
Question 9
Incorrect
-
Following a fracture in the fibula, an artery contained in a fibrous canal between tibialis posterior and flexor hallucis longus was lacerated. Which of the following arteries was injured?
Your Answer: Posterior tibial
Correct Answer: Peroneal
Explanation:The peroneal artery is deeply seated at the back of the fibular side of the leg, contained in a fibrous canal between the tibialis posterior and the flexor hallucis longus.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 10
Correct
-
What forms the pelvic diaphragm?
Your Answer: Levator ani and coccygeus muscles
Explanation:The pelvic diaphragm is formed by the levator ani and the coccygeus muscles. The levator ani forms the greater part of the pelvic floor supporting the viscera in the pelvic cavity.
-
This question is part of the following fields:
- Anatomy
- Pelvis
-
-
Question 11
Correct
-
During a street fight a boy sustained a laceration below the elbow. It was a deep cut that led to profuse bleeding from an artery situated on the supinator muscle immediately below the elbow. The vessel most likely to have been injured is?
Your Answer: Radial recurrent artery
Explanation:The radial recurrent artery is situated on the supinator muscle then passing between the brachialis and the brachioradialis muscles. It originates from the radial artery and ends by anastomosing with the terminal part of the Profunda brachii.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 12
Incorrect
-
A 65-year old man, known with Type 2 diabetes and chronic renal failure, is likely to eventually present with which of the following conditions?
Your Answer: Cushing syndrome
Correct Answer: Secondary hyperparathyroidism
Explanation:When the parathyroid glands secrete excess parathyroid hormone (PTH) in response to hypocalcaemia, it is known as Secondary hyperparathyroidism and is often seen in patients with renal failure. In chronic renal failure, the kidneys fail to excrete adequate phosphorus and also fail to convert enough vitamin D to its active form. This leads to formation of insoluble calcium phosphate in the body which ultimately causes hypocalcaemia. The glands then undergo hyperplasia and hypertrophy leading to secondary hyperparathyroidism. Symptoms include bone and joint pains, along with limb deformities. The raised PTH also results in pleiotropic effects on blood, the immune system and nervous system.
-
This question is part of the following fields:
- Endocrine
- Pathology
-
-
Question 13
Correct
-
A 42 year old women presents with end stage renal failure and is prepared to receive a kidney from her husband. HLA testing showed that they are not a 100% match and she is given immunosuppressant therapy for this. Three months later when her renal function tests were performed she showed signs of deteriorating renal function, with decreased renal output, proteinuria of +++ and RBCs in the urine. She was given antilymphocyte globulins and her condition reversed. What type of graft did this patient receive?
Your Answer: Allograft
Explanation:Allograft describes a graft between two of the same species. As the donor and the recipients are history-incompatible, rejection of the graft is common and is controlled by immunosuppressive drug therapy. Isograft and syngraft are synonymous and referred to a graft transferred between genetically identical individuals e.g. identical twins. In this case rejection is rare as they are history-compatible.
Autograft refers to transfer of one part of the body to another location.
Xenograft is transfer of tissue from another species e.g. pig to human in valve replacement surgeries and rejection is very high.
-
This question is part of the following fields:
- Inflammation & Immunology; Renal
- Pathology
-
-
Question 14
Incorrect
-
If a patient takes long-term corticosteroid therapy, which of the following diseases is most likely to develop?
Your Answer: Paget’s disease of bone
Correct Answer: Osteoporosis
Explanation:One of the complications of long-term intake of corticosteroids is osteoporosis. Some guidelines recommend prophylactic calcium and vitamin D supplementation in patients who take more than 30 mg hydrocortisone or 7.5 mg of prednisolone daily.
-
This question is part of the following fields:
- Orthopaedics
- Pathology
-
-
Question 15
Correct
-
Lung compliance is increased by:
Your Answer: Emphysema
Explanation:Lung compliance is increased by emphysema, acute asthma and increasing age and decreased by alveolar oedema, pulmonary hypertension, atelectasis and pulmonary fibrosis.
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 16
Incorrect
-
When exposing the right saphenofemoral junction for flush-ligation of the saphenous vein, which of the following is the most likely to be seen passing through this opening?
Your Answer: Saphenous nerve
Correct Answer: Superficial external pudendal artery
Explanation:The saphenous opening is an oval opening in the fascia lata. It is covered by the cribriform fascia and It is so called because it is perforated by the great saphenous vein and by numerous blood and lymphatic vessels and the superficial external pudendal artery pierces it.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 17
Correct
-
A 40-year old Caucasian male came to the hospital with complaints of fatigue and lethargy. On examination, he was found to have raised blood pressure. Urine examination showed >300 mg/dl proteinuria (4+) and 24-hour urine protein 3.5g. No glucose, blood, nitrites, urobilinogen or casts were present in urine. What is the most likely diagnosis?
Your Answer: Membranous glomerulonephritis
Explanation:Membranous glomerulonephritis or nephropathy, is a renal disorder with insidious course and usually affects people aged 30-50 years. 85% cases are primary (or idiopathic). The other 15% are secondary to autoimmune conditions like SLE, infections like malaria or hepatitis B, drugs like captopril and NSAIDs, or malignancies (particularly lung or colonic carcinoma). This disease is caused due to circulating immune complexes which are said to form by binding of antibodies to antigens in glomerular basement membrane. This antigens could be endogenous or derived from systemic circulation. This immune complex triggers the complement system, resulting in formation of membrane attack complex (MAC) on glomerular epithelial cells. This further results in release of proteases and oxidants which damage the capillaries making them ‘leaky’. Moreover, the epithelial cells also secrete a mediator to reduce nephron synthesis and distribution.
-
This question is part of the following fields:
- Pathology
- Renal
-
-
Question 18
Correct
-
Following nerve injury, paralysis of the quadriceps femoris muscle occurs. Which of the following movements will be affected?
Your Answer: Extension of the leg
Explanation:The quadriceps muscle is a great extensor of the thigh. Therefore, following nerve injury or cutting nerve supply to the quadriceps will affect extension of the thigh
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 19
Correct
-
A previously healthy 40-year-old housewife suddenly complains of a headache and loses consciousness. A CT scan reveals subarachnoid haemorrhage. Which of the following is the most probable cause?
Your Answer: Ruptured berry aneurysm
Explanation:Saccular aneurysms, also known as berry aneurysms, appear as a round outpouching and are the most common form of cerebral aneurysm. They are a congenital intracranial defect, and haemorrhage can occur at any age, but is most common between the ages of 40-65 years. A second rupture (rebleeding) sometimes occurs, most often within about 7 days of the first bleed.
-
This question is part of the following fields:
- Neurology
- Pathology
-
-
Question 20
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.
-
This question is part of the following fields:
- Gastroenterology
- Physiology
-
-
Question 21
Correct
-
Where is the foramen ovale located?
Your Answer: Sphenoid
Explanation:The foramen ovale is an oval shaped opening in the middle cranial fossa located at the posterior base of the greater wing of the sphenoid bone, lateral to the lingula. It transmits the mandibular division of the trigeminal nerve (CN Vc), accessory meningeal artery, emissary veins between the cavernous sinuses and pterygoid plexus, otic ganglion, and occasionally the nervus spinosus and lesser petrosal nerve.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 22
Correct
-
A 65-year-old female is taking different medications for various medical conditions. Which medication would most likely predispose the patient to develop hyperkalaemia?
Your Answer: Spironolactone
Explanation:The most important potential side effect of spironolactone is hyperkalaemia (high potassium levels), which, in severe cases, can be life-threatening. Hyperkalaemia in these patients can present as a non anion-gap metabolic acidosis.
-
This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
-
-
Question 23
Incorrect
-
The dilator pupillae muscle is innervated by postganglionic sympathetic fibres. Where do the postganglionic sympathetic fibres originate?
Your Answer: Brain
Correct Answer: Superior cervical ganglion
Explanation:The postganglionic sympathetic axons are derived from the superior cervical ganglion and innervate the eye and lacrimal gland allowing for vasoconstriction of the iris and sclera, pupillary dilation, widening of the palpebral fissure, and a reduction in tear production.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 24
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.
-
This question is part of the following fields:
- Orthopaedics
- Pathology
-
-
Question 25
Correct
-
In which of the following conditions will the oxygen-haemoglobin dissociation curve shift to the right?
Your 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 26
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 27
Correct
-
An amateur body-builder complains of increasing pain in his right shoulder after a few days of intense training. A surgeon aspirates clear fluid from his subdeltoid region. What's the most likely diagnosis?
Your Answer: Bursitis
Explanation:Bursae are potential cavities that contain synovial fluid, found in areas where friction occurs. Their function is to minimise friction and facilitate movement. Bursitis is the inflammation of one or more bursae, and they can occur in the shoulder, elbow, knee, ischium, amongst other joints. Acute bursitis can appear after strenuous exercise or activity, and chronic bursitis can develop following previous bursitis or trauma. Acute bursitis causes pain, tenderness, and swelling.
-
This question is part of the following fields:
- Orthopaedics
- Pathology
-
-
Question 28
Correct
-
the action of the semimembranosus muscle is:
Your Answer: Extension of the hip and flexion of the knee
Explanation:the semimembranosus is situated at the back and medial side of the thigh. It arises from the upper and outer impression on the tuberosity of the ischium, above and lateral to the biceps femoris and semitendinosus. It is inserted mainly into the horizontal groove on the posterior medial aspect of the medial condyle of the tibia. it flexes the knee and assists in extension of the hip.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 29
Correct
-
The nasolacrimal duct is a membranous canal. It extends from the lower part of the lacrimal sac and drains into which structure?
Your Answer: Inferior meatus
Explanation:The nasolacrimal duct carries tears from the lacrimal sac of the eye into the nasal cavity. The duct begins in the eye socket between the maxillary and lacrimal bones, from where it passes downwards and backwards. The opening of the nasolacrimal duct into the inferior nasal meatus of the nasal cavity is partially covered by a mucosal fold (valve of Hasner or plica lacrimalis). Excess tears flow through the nasolacrimal duct which drains into the inferior nasal meatus.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 30
Correct
-
Which of the following coagulation factors is responsible for the formation of a complex with tissue factor to activate factors IX and X?
Your Answer: Factor VII
Explanation:Factor VII, also known as proconvertin or stable factor, is a vitamin K–dependent protein that plays a central role in haemostasis and coagulation. Tissue factor is a protein that is normally not exposed on the surface of intact blood vessels. Damage to the vascular lumen leads to tissue factor exposure. The exposed tissue factor binds to factor VII. This facilitates the activation of factor VII to factor VIIa.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 31
Correct
-
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: 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.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 32
Incorrect
-
A urologist makes a transverse suprapubic incision to retrieve a stone from the urinary bladder. Which of the following abdominal wall layers will the surgeon NOT traverse?
Your Answer: Transversalis fascia, extraperitoneal fat and peritoneum
Correct Answer: Posterior rectus sheath
Explanation:Pfannenstiel incision (a transverse suprapubic incision) is made below the arcuate line. Thus, there is no posterior layer of the rectus sheath here, only the transversalis fascia lines the inner layer of the rectus abdominis. The layers traversed include: skin, superficial fascia (fatty and membranous), deep fascia, anterior rectus sheath, rectus abdominis muscle, transversalis fascia, extraperitoneal connective tissue and peritoneum.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 33
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, Decrease
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 34
Incorrect
-
A 50 year old female patient with an history of chronic headache was scheduled for CT scan. If the CT scan revealed a tumour at the horn of the lateral ventricle, which of the following structures is most likely to be compressed by this tumour?
Your Answer: Frontal lobe
Correct Answer: Fibres of the corpus callosum
Explanation:The ventricular system of the brain is made up of four ventricles namely; two lateral and a third and forth ventricle. The ventricles are the site of the development of the cerebrospinal fluid. The left and right lateral ventricles are located in each of the brain’s hemispheres. The roof of the lateral ventricles are made up of the fibres of the corpus callosum. This is the structure that would be compressed by the a tumour on the roof of the lateral ventricles.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 35
Correct
-
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: 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 36
Incorrect
-
Blood supply to the posterior compartment of the thigh is supplied by which artery?
Your Answer: Superior gluteal
Correct Answer: Perforating
Explanation:There are usually 3 perforating arteries:
The first gives branches to the adductor brevis and magnus, biceps femoris and gluteus maximus and anastomoses with the inferior gluteal, medial and lateral femoral circumflex.
The second artery supplies the posterior femoral muscles and anastomose with the first and third perforating vessels.
The third supplies the posterior femoral muscles.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 37
Incorrect
-
Which of the following arteries, if ligated, will most likely affect blood supply to the pancreas?
Your Answer: Common hepatic
Correct Answer: Superior mesenteric
Explanation:The pancreas is a glandular organ in the body that produces important hormones such as insulin and glucagon. Its blood supply is from branches of the coeliac artery, superior mesenteric artery and the splenic artery. These are the arteries that if ligated, would affect blood supply to the pancreas.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 38
Incorrect
-
Under normal conditions, what is the major source of energy of cardiac muscles?
Your Answer: Glucose
Correct 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.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 39
Correct
-
A 7-month-old abandoned baby with congenital non-communicating hydrocephalus is hosted by a clinic at its new-born hostel. A CT scan of the baby's brain reveals what might be a blockage of the ventricular system between the third and the fourth ventricles. Which of the following is the most likely blocked structure?
Your Answer: Cerebral aqueduct
Explanation:The drainage of cerebral spinal fluid from the third ventricle to the fourth ventricle is carried out by the cerebral aqueduct. The cerebral aqueduct is the narrowest passageway in the entire ventricular system and thus forms the most common site of blockage of flow of cerebrospinal fluid. The interventricular foramen allows passage of CSF to the third ventricle. The foramen of Luschka and Magendie are located on the fourth ventricle and allow passage of CSF to the subarachnoid space from the ventricular system. The pontine cistern is a space located on the ventral aspect of the pons. The cisterna magna is an opening on the subarachnoid space between the pia matter and the arachnoid.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 40
Incorrect
-
A 45-year old man presents with sclerosing cholangitis, blood in his stools and apparent iron deficiency anaemia. What will be the most likely finding on his colonic biopsy?
Your Answer: Diverticulitis
Correct Answer: Pseudopolyps
Explanation:Sclerosing cholangitis along with the passage of blood in stools suggests ulcerative colitis affecting the mucosa and submucosa of rectum and colon, with a sharp demarcation with the normal tissue. The musclaris layer is involved in severe cases. Initially, the mucosa is erythematous, friable with scattered haemorrhagic areas and loss of normal vascular pattern. Severe disease is indicated by presence of large mucosal ulcers with purulent exudate. There can be islands of normal mucosa between the ulcerated mucosa, along with few hyperplastic inflammatory mucosal lesions (pseudopolyps). Ulcerative colitis does not lead to development of fistulas or abscesses.
-
This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
-
-
Question 41
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.
-
This question is part of the following fields:
- Pathology
- Pharmacology
-
-
Question 42
Incorrect
-
Glucose is not secreted by the kidneys, and is filtered without a limit. What is the transport maximum for glucose?
Your Answer: 100 mg/dl
Correct Answer: 300 mg/dl
Explanation:Transport maximum (or Tm) refers to the point at which increases in concentration do not result in an increase in movement of a substance across a membrane. Glucose is not secreted, thus excretion = filtration – reabsorption. Both filtration and reabsorption are directly proportional to the concentration of glucose in the plasma. However, reabsorption has a transport maximum of about 300 mg/dl in healthy nephrons, while filtration has effectively no limit (within reasonable physiological ranges). So, if the concentration rises above 300 mg/dl, the body cannot retain all the glucose, leading to glucosuria. Glucosuria is nearly always caused by elevated blood glucose levels, most commonly due to untreated diabetes mellitus.
-
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 43
Correct
-
Carbachol is a cholinergic agonist. In which of these cases should carbachol be administered?
Your Answer: Cataract surgery
Explanation:Carbachol (carbamylcholine) is a cholinergic agent, a choline ester and a positively charged quaternary ammonium compound. It is primarily used for various ophthalmic purposes, such as for treating glaucoma, or for use during ophthalmic surgery. It is usually administered topically to the eye or through intraocular injection. It is not well absorbed in the gastro-intestinal tract and does not cross the blood–brain barrier.
-
This question is part of the following fields:
- Pathology
- Pharmacology
-
-
Question 44
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 45
Correct
-
Rapid Eye Movement (REM) sleep is typically associated with:
Your Answer: Penile erections
Explanation:Normal sleep comprises of alternate cycles between slow-wave sleep (non-REM sleep) and REM sleep. REM sleep is characterized by increased metabolic brain activity and EEG desynchronization. Somnambulism (sleepwalking), enuresis (bedwetting) and night terrors all occur during slow-wave sleep or during arousal from slow-wave sleep. In comparison, REM sleep is characterized by hypotonia of major muscle groups (excluding ocular muscles), dreams, nightmares and penile erection.
-
This question is part of the following fields:
- Neurology
- Physiology
-
-
Question 46
Incorrect
-
During a surgical procedure involving the carotid artery, which nerve in the cervical plexus of nerves that is embedded in the carotid sheath is most susceptible to injury?
Your Answer: Phrenic nerve
Correct Answer: Ansa cervicalis
Explanation:The ansa cervicalis is a loop of nerves that are part of the cervical plexus. They lie superficial to the internal jugular vein in the carotid triangle. Branches from the ansa cervicalis innervate the sternohyoid, sternothyroid and the inferior belly of the omohyoid. The superior root of the ansa cervicalis is formed by a branch of spinal nerve C1. These nerve fibres travel in the hypoglossal nerve before leaving to form the superior root. The superior root goes around the occipital artery and then descends embedded in the carotid sheath. It sends a branch off to the superior belly of the omohyoid muscle and is then joined by the inferior root. The inferior root is formed by fibres from spinal nerves C2 and C3.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 47
Incorrect
-
An experiment was conducted in which the skeletal muscle protein (not smooth muscle) involved in contraction was selectively inhibited. Which protein was inhibited?
Your Answer: Actin
Correct Answer: Troponin
Explanation:The mechanism of contraction of smooth muscles is different from that of skeletal muscles in which the contractile protein is troponin whilst in smooth muscle contraction is a protein called calmodulin. Calmodulin reacts with calcium ions and stimulates the formation of myosin crossbridges.
-
This question is part of the following fields:
- General
- Physiology
-
-
Question 48
Incorrect
-
The gastrosplenic ligament also known as the gastrolienal ligament is the structure that connects the greater curvature of the stomach to the hilum of the spleen. Which of the following arteries would most likely be injured if a surgeon accidentally tore this ligament?
Your Answer: Splenic
Correct Answer: Short gastric
Explanation:The short gastric arteries arise from the end of the splenic arteries and form five to seven branches. The short gastric arteries inside the gastrosplenic ligament from the left to the right, supply the greater curvature of the stomach. The hepatic artery proper runs inside the hepatoduodenal ligament. The right gastric artery and the left gastric artery are contained in the hepatogastric ligament. The caudal pancreatic artery branches off from the splenic artery and supplies the tail of the pancreas. The middle colic artery supplies the transverse colon. The splenic artery does not travel in the gastrosplenic ligament and so it would not be damaged by a tear to this ligament.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 49
Correct
-
A 28-year old lady comes to the surgical clinic with a recently detected lump in her right breast. On examination, the lump is found to be 1cm, rubbery, mobile with no palpable axillary nodes. Mammography reveals no microcalcifications and the opposite breast appears normal. What is the likely diagnosis?
Your Answer: Fibroadenoma
Explanation:A benign breast tumour, fibroadenoma is common below the age of 30 years and occurs due to oestrogenic excess. It is characterised by proliferation of both glandular and stromal elements. Fibroadenomas are usually solitary and are mobile, not fixed to surrounding structures. The tumour is elastic, nodular and encapsulated with a grey-white cut surface. The two main histological types include intracanalicular and pericanalicular types, with both types often present in the same tumour. In the intracanalicular type, the stromal proliferation component predominates causing compression of ducts making them appear slit-like. In pericanalicular type, the fibrous stroma dominates around the ductal spaces so that they remain oval on cross section.
-
This question is part of the following fields:
- Pathology
- Women's Health
-
-
Question 50
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.
-
This question is part of the following fields:
- Microbiology
- Pathology
-
-
Question 51
Correct
-
Signals pass through neuromuscular junctions via the neurotransmitter acetylcholine. After release from the skeletal neuromuscular junction, acetylcholine:
Your Answer: Causes postsynaptic depolarisation
Explanation:Acetylcholine is released from the presynaptic membrane into the cleft where it binds to the ion gated channels on the post synaptic membrane, causing them to open. This results in sodium entering into the fibre and further depolarizing it, creating an action potential.
-
This question is part of the following fields:
- General
- Physiology
-
-
Question 52
Correct
-
Into which vein does the left and right inferior thyroid veins drain?
Your Answer: Brachiocephalic vein
Explanation:The brachiocephalic vein is formed by the confluence of the subclavian and internal jugular veins. In addition it receives drainage from: the left and right internal thoracic veins (also called internal mammary veins), left and right inferior thyroid veins and the left superior intercostal vein.
The superior thyroid veins and middle thyroid veins drain into the internal jugular vein. The right and left inferior thyroid veins to drain into their respective brachiocephalic veins (right and left). -
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 53
Correct
-
Which of the following structures is not easily palpable?
Your Answer: Styloid process of the temporal bone
Explanation:The styloid process is a thin, pointed process that projects antero-inferiorly from the base of the petrous temporal bone. It can vary in length from a short, stubby process to a slender, four to five centimetre rod. It forms from the cranial elements of the second pharyngeal arch. The tympanic plate of the temporal bone ensheathes the base of this process. The pointed, projecting portion of the process provides attachment to the stylohyoid and stylomandibular ligaments, and to three muscles – the styloglossus, stylohyoid, and stylopharyngeus. As the styloid process is covered by the various muscles, it is not easily palpable in live subjects.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 54
Correct
-
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
-
This question is part of the following fields:
- Microbiology
- Pathology
-
-
Question 55
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: Glucose
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.
-
This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
-
-
Question 56
Incorrect
-
In the glomerulus of the kidney, the mesangium is a structure associated with the capillaries. It has extraglomerular mesangial cells that:
Your Answer: Provide structural support for and regulate blood flow of the glomerular capillaries by their contractile activity
Correct 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.
-
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 57
Correct
-
A 50-year old lady presented to the clinic with chronic pain in the abdomen. On physical examination, she was found to be pale. Further investigations revealed a decrease in both serum iron and total iron-binding capacity, along with an increase in serum ferritin. These findings are seen in:
Your Answer: Anaemia of chronic disease
Explanation:Anaemia of chronic disease is characterized by low serum iron, iron-binding capacity and saturation with increased ferritin (storage iron). Haemolytic anaemia is characterized by normal iron levels as the haemoglobin released from the haemolysed red blood cells is recycled. Anaemia due to chronic blood loss leads to low serum iron, low ferritin and high total iron-binding capacity (TIBC). Malabsorption, especially with duodenal involvement can also lead to iron deficiency anaemia with low ferritin and high TIBC. Megaloblastic anaemia due to vitamin B12 and folate deficiency is not associated with abnormalities in metabolism of iron.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 58
Incorrect
-
What is the linea aspera:
Your Answer: Is a landmark on the tibia
Correct Answer: Serves as an attachment for adductors of the thigh
Explanation:The linea aspera is a prominent longitudinal ridge or crest on the middle third of the femur. It has a medial and a lateral lip and a narrow, rough, intermediate line. The vastus medialis arises from the medial lip of the linea aspera and has superior and inferior prolongations. The vastus lateralis takes origin from the lateral lip . The adductor magnus is inserted into the linea aspera. Two muscles are attached between the vastus lateralis and the adductor magnus: the gluteus maximus is inserted above and the short head of the biceps femoris arises below. Four muscles are inserted between the adductor magnus and the vastus medialis: the iliacus and pectineus superiorly, and the adductor brevis and adductor longus inferiorly.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 59
Correct
-
A sudden loud sound is more likely to result in cochlear damage than a slowly developing loud sound. This is because:
Your Answer: There is a latent period before the attenuation reflex can occur
Explanation:On transmission of a loud sound into the central nervous system, an attenuation reflex occurs after a latent period of 40-80 ms. This reflex contracts the two muscles that pull malleus and stapes closer, developing a high degree of rigidity in the entire ossicular chain. This reduces the ossicular conduction of low frequency sounds to the cochlea by 30-40 decibels. In this way, the cochlea is protected from damage due to loud sounds (these are low frequency sounds) when they develop slowly.
-
This question is part of the following fields:
- Neurology
- Physiology
-
-
Question 60
Correct
-
In order to arrest sudden bleeding during pericardiectomy that started after accidental injury to a major vasculature in the pericardium; the surgeon inserted his left index finger through the transverse pericardial sinus, pulled forward on the two large vessels lying ventral to his finger, and compressed these vessels with his thumb to control the bleeding. Which vessels were these?
Your Answer: Pulmonary trunk and aorta
Explanation:Transverse pericardial sinus: located behind two great vessels (aorta and pulmonary trunk) and in front of the superior vena cava and is accessed from above as in this case. The brachiocephalic trunk is located above the pericardium and the right pulmonary artery is above the pericardial reflections.
-
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 61
Correct
-
A 45 year old man who complains of chronic post prandial, burning epigastric pain undergoes a gastrointestinal endoscopy. There is no apparent mass or haemorrhage and a biopsy is taken from the lower oesophageal mucosa just above the gastro-oesophageal junction. The results reveal the presence of columnar cells interspersed with goblet cells. Which change best explains the above mentioned histology?
Your Answer: Metaplasia
Explanation:Metaplasia is the transformation of one type of epithelium into another as a means to better cope with external stress on that epithelium. In this case metaplasia occurs due to the inflammation resulting from gastro-oesophageal reflux disease. Dysplasia is disordered cellular growth. Hyperplasia is an increase in cell number but not cell type i.e. transformation. Carcinoma is characterized by cellular atypia. Ischaemia would result in necrosis with ulceration. Carcinoma insitu involves dysplastic atypical cells with the basement membrane intact and atrophy would mean a decrease in number of cells.
-
This question is part of the following fields:
- Cell Injury & Wound Healing; Gastrointestinal
- Pathology
-
-
Question 62
Incorrect
-
A 32-year-old man presents to the doctor complaining of pain in his left calf whilst walking. He says that the pain goes away after a short period of rest but starts again during exercise or walking. The man reveals he has been a smoker for the last 15 years. His blood pressure, blood sugar and cholesterol level are normal. Artery biopsy shows intraluminal thrombosis and vasculitis. What's is the most likely cause of these findings?
Your Answer: Giant-cell arteritis
Correct Answer: Buerger's disease
Explanation:Thromboangiitis obliterans, also known as Buerger’s disease, is a rare type of occlusive peripheral arterial disease, usually seen in smokers, most commonly in men aged 20 to 40. Symptoms most often include intermittent claudication, skin changes, painful ulcers on extremities, pain in the extremities during rest and gangrene. Diagnosis is based on clinical findings, arteriography, echocardiography, and computed tomography angiography. A difference in blood pressure between arms, or between the arms and legs is a common finding. Electrocardiographic findings include nonspecific abnormality or normal results.
-
This question is part of the following fields:
- Cardiovascular
- Pathology
-
-
Question 63
Incorrect
-
A 70-year-old man suffers an ischaemic stroke and develops a left homonymous hemianopia. Where is the likely infarct?
Your Answer: Left occipital lobe
Correct Answer: Right occipital lobe
Explanation:The man has a left homonymous hemianopia which means he is unable to view objects in the left visual field. This information is processed by the right primary visual cortex which lies in the right occipital lobe.
-
This question is part of the following fields:
- Neurology
- Pathology
-
-
Question 64
Correct
-
The mechanism of action of streptokinase involves:
Your 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.
-
This question is part of the following fields:
- General
- Physiology
-
-
Question 65
Correct
-
A glycogen storage disorder is characterised by increased liver glycogen with a normal structure and no increase in serum glucose after oral intake of a protein-rich diet. Deficiency of which of the following enzymes is responsible for this disorder?
Your Answer: Glucose-6-phosphatase
Explanation:The most common glycogen storage disorder is von Gierke’s disease or glycogen storage disease type I. It results from a deficiency of enzyme glucose-6-phosphatase which affects the ability of liver to produce free glucose from glycogen and gluconeogenesis; leading to severe hypoglycaemia. There is also increased glycogen storage in the liver and kidneys causing enlargement and various problems in their functioning. The disease also causes lactic acidosis and hyperlipidaemia. The main treatment includes frequent or continuous feedings of corn-starch or other carbohydrates.
-
This question is part of the following fields:
- Gastroenterology
- Physiology
-
-
Question 66
Correct
-
A 46-year old female patient experienced a stroke that affected her glossopharyngeal nerve. Damage to the glossopharyngeal nerve would most likely:
Your 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.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 67
Incorrect
-
Which of the following conditions may cause hypervolaemic hyponatraemia?
Your Answer: Protracted vomiting
Correct Answer: Cirrhosis
Explanation:Hypovolaemic hyponatraemia: reduced extracellular fluid
Renal loss of sodium and water; urine Na >20 mmol/day
Causes:
Diuretic use
Salt wasting nephropathy
Cerebral salt wasting
Mineralocorticoid deficiency/adrenal insufficiency
Renal tubular acidosis
Extrarenal loss of sodium and water with renal conservation; urine Na <20 mmol/day
Causes:
Burns
Gastrointestinal loss
Pancreatitis
Blood loss
3rd space loss (bowel obstruction, peritonitis)Hypervolaemic hyponatraemia: expanded intracellular fluid and extracellular fluid but reduced effective arterial blood volume
Causes:
Congestive cardiac failure
Cirrhosis
Nephrotic syndromeEuvolaemic hyponatraemia: expanded intracellular and extracellular fluid but oedema absent
Causes:
Thiazide diuretics (can be euvolaemic or hypovolaemic)
Hypothyroidism
Adrenal insufficiency (can be euvolaemic or hypovolaemic)
SIADH (cancer, central nervous system disorders, drugs, pulmonary disease, nausea, postoperative pain, HIV, infection, Guillain‐Barre syndrome, acute intermittent porphyria)
Decreased solute ingestion (beer potomania/tea and toast diet) -
This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
-
-
Question 68
Correct
-
A 45-year-old pregnant woman develops high blood pressure at 20 weeks. She complains of headaches and swollen feet, and a test reveals proteinuria (350 mg/day). Which of the following is the most likely diagnosis?
Your Answer: Pre-eclampsia
Explanation:Pre-eclampsia (PE) is a disorder of pregnancy characterized by the onset of high blood pressure (two separate readings taken at least 6 h apart of 140/90 or more) and often a significant amount of protein in the urine (>300 mg of protein in a 24-h urine sample). While blood pressure elevation is the most visible sign of the disease, it involves generalised damage to the maternal endothelium of the kidneys and liver, with the release of vasopressive factors only secondary to the original damage. Pre-eclampsia may develop at varying times within pregnancy and its progress differs among patients; most cases present pre-term. It has no known cure apart from ending the pregnancy (induction of labour or abortion). It may also present up to 6 weeks post partum. Risk factors for pre-eclampsia include obesity, prior hypertension, older age, and diabetes mellitus.
-
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 69
Correct
-
A 49-year-old woman with acute renal failure has a total plasma [Ca2+] = 2. 5 mmol/l and a glomerular filtration rate of 160 l/day. What is the estimated daily filtered load of calcium?
Your Answer: 240 mmol/day
Explanation:Calcium is the most abundant mineral in the human body. The average adult body contains in total approximately 1 kg of calcium of which 99% is in the skeleton in the form of calcium phosphate salts. The extracellular fluid (ECF) contains approximately 22 mmol, of which about 9 mmol is in the plasma. About 40% of total plasma Ca2+ is bound to proteins and not filtered at the glomerular basement membrane. Therefore, the estimated daily filtered load is 1.5 mmol/l × 160 l/day = 240 mmol/day. The exact amount of free versus total Ca2+ depends on the blood pH: free Ca2+ increases during acidosis and decreases during alkalosis.
-
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 70
Correct
-
Which of the following is the most accurate test for the diagnosis of primary syphilis?
Your Answer: Dark-field microscopy
Explanation:Primary syphilis is transmitted via sexual contact. Lesions on genitalia, called a chancre occur after an asymptomatic incubation period of 10-90 days (average 21 days) after exposure. This chancre is a typically solitary (can be multiple), firm, painless, ulceration over the skin at the point of exposure to spirochete, seen on penis, vagina or rectum. It heals spontaneously after 4-6 weeks. Local lymphadenopathy can be seen.
Diagnosis is made by microscopy of fluid from lesion using dark-field illumination, taking care to not confuse with other treponemal disease. Screening tests include rapid plasma regain (RPR) and Venereal Diseases Research Laboratory (VDRL) tests. False positives are known to occur with these tests and can be seen in viral infections like hepatitis, varicella, Epstein-Barr virus, tuberculosis, lymphoma, pregnancy and IV drug use. More specific tests should therefore be carried out in case these screening tests are positive.
The Treponema pallidum hemagglutination assay (TPHA) and the fluorescent treponemal antibody absorption (FTAABS) test are based on monoclonal antibodies and immunofluorescence and are more specific. However, they can too show false positives with other treponemal diseases like yaws or pinta. Other confirmatory tests include those based on enzyme-linked immunoassays.
-
This question is part of the following fields:
- Pathology
- Urology
-
-
Question 71
Correct
-
A 39-year-old man, after radiological evaluation and thoracentesis, was found to have chylothorax. What is the most probable cause of this diagnose?
Your Answer: Mediastinal malignant lymphoma
Explanation:Chylothorax is a potentially lethal condition characterized by fluid (chyle) accumulation in the pleural cavity, resulting from disruption of lymphatic drainage in the thoracic duct. Chyle is a fluid rich in triglycerides and chylomicrons and can originate from the thorax, the abdomen or both. Malignant tumours, especially lymphoma, are the most common causes of nontraumatic chylothorax. Bronchogenic carcinoma and trauma are the most common causes after lymphomas. Other rare causes of chylothorax are; granulomatous diseases, tuberculosis, congenital malformations, nephrotic syndrome, hypothyroidism, cirrhosis, decompensated heart failure and idiopathic chylothorax.
-
This question is part of the following fields:
- Pathology
- Respiratory
-
-
Question 72
Incorrect
-
Choose the most correct answer regarding the obturator internus muscle.
Your Answer: It shares innervation with the obturator externus
Correct Answer: It emerges from the pelvis through the lesser sciatic foramen
Explanation:The obturator internus arises from the inner surface of the anterolateral wall of the pelvis and the pelvic surface of the obturator membrane. The fibres converge rapidly towards the lesser sciatic foramen and end in four or five tendinous bands and leave the pelvis through the lesser sciatic foramen.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 73
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.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 74
Incorrect
-
Action potentials are used extensively by the nervous system to communicate between neurones and muscles or glands. What happens during the activation of a nerve cell membrane?
Your Answer: Sodium ions flow outward
Correct Answer: Sodium ions flow inward
Explanation:During the generation of an action potential, the membrane gets depolarized which cause the voltage gated sodium channels to open and sodium diffuses inside the neuron, resulting in the membrane potential moving towards a positive value. This positive potential will then open the voltage gated potassium channels and cause more K+ to move out decreasing the membrane potential and restoring the membrane potential to its resting value.
-
This question is part of the following fields:
- General
- Physiology
-
-
Question 75
Correct
-
A patient is suspected to have Blastomyces dermatidis infection. The patient contracted the disease most likely through which port of entry?
Your Answer: Respiratory tract
Explanation:Blastomycosis disease is a fungal infection acquired through inhalation of the spores. It caused by the organism Blastomyces dermatitidis and manifests as a primary lung infection in about 70% of cases. The onset is relatively slow and symptoms are suggestive of pneumonia.
-
This question is part of the following fields:
- Microbiology
- Pathology
-
-
Question 76
Incorrect
-
A 60-year-old male who was admitted due to cerebrovascular disease on his 5th hospital stay developed pneumonia. The most likely organism that causes hospital acquired pneumonia is pseudomonas aeruginosa. What is the most likely mechanism for the pathogenesis on pseudomonas infection?
Your Answer: Inhibition of cGMP
Correct Answer: Exotoxin
Explanation:Pseudomonas aeruginosa is a common Gram-negative, rod-shaped bacterium that can cause disease in plants and animals, including humans. It is citrate, catalase, and oxidase positive. P. aeruginosa uses the virulence factor exotoxin A to inactivate eukaryotic elongation factor 2 via ADP-ribosylation in the host cell, much the same as the diphtheria toxin does. Without elongation factor 2, eukaryotic cells cannot synthesize proteins and necrotise. The release of intracellular contents induces an immunologic response in immunocompetent patients.
-
This question is part of the following fields:
- Microbiology
- Pathology
-
-
Question 77
Correct
-
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.
-
This question is part of the following fields:
- General
- Physiology
-
-
Question 78
Incorrect
-
During laparoscopic surgery to repair a direct inguinal hernia in a 68-year old man, the surgeon asked the registrar to look at the medial inguinal fossa to identify the direct inguinal hernia. To do so, she would have to look at the area that is between the:
Your Answer: Inferior epigastric artery and lateral umbilical fold
Correct Answer: Medial umbilical ligament and inferior epigastric artery
Explanation:The medial umbilical fold is made by the medial umbilical ligament-which is the obliterated portion of the umbilical artery, while the lateral umbilical fold is a fold of peritoneum over the inferior epigastric vessels. The median umbilical fold is a midline structure made by the median umbilical ligament i.e. the obliterated urachus. The medial inguinal fossa is the space on the inner abdominal wall between the medial umbilical fold and the lateral umbilical fold. It is place in the abdominal wall where there is an area of weak fascia i.e. the inguinal triangle through which direct inguinal hernias break through. The lateral inguinal fossa on the other hand is a space lateral to the lateral umbilical fold. Indirect inguinal hernias push through this space.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 79
Incorrect
-
During clinic, a medical student conducts a physical examination on a teenage boy with a lump in the inguinal region. The lump is protruding from the superficial inguinal ring. The student correctly concluded that it was:
Your Answer: Definitely an indirect inguinal hernia
Correct Answer: Either a direct or an indirect inguinal hernia
Explanation:It is not possible to tell if an inguinal hernia is direct or indirect just by palpating it. Despite the fact that indirect inguinal hernias commonly come out of the superficial inguinal ring to enter the scrotum, direct inguinal hernia might still do this.
Femoral hernia goes through the femoral ring into the femoral canal (has nothing to do with the superficial inguinal ring).
Superficial inguinal lymph nodes lie in the superficial fascia parallel to the inguinal ligament; it would therefore feel more superficial and would not be mistaken for a hernia protruding through the inguinal ring.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 80
Correct
-
The transmembrane proteins responsible for resting membrane potential of vascular smooth muscle cells was blocked by a drug. Which of the following transmembrane proteins were blocked by this drug?
Your Answer: K+ channels
Explanation:The resting membrane potential is due to selective permeability of the membrane to potassium ions. The Na/K pump is responsible for the generation of a gradient across the membrane and it is due to the inherent ability of the K channels to allow diffusion back into the nerve at rest which charges the cells. In reality, the resting membrane potential is more positive because of small contributions by Na+ channels, Cl− channels and non-selective cation channels.
-
This question is part of the following fields:
- General
- Physiology
-
-
Question 81
Correct
-
What intrinsic muscle of the larynx is responsible for the tensing of the vocal cords?
Your Answer: Cricothyroid muscle
Explanation:The cricothyroid muscle is the only tensor muscle of the larynx aiding with phonation. It attaches to the anterolateral aspect of the cricoid and the inferior cornu and lower lamina of the thyroid cartilage. Its action tilts the thyroid forward to help tense the vocal cords.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 82
Incorrect
-
A 65-year-old man with no history of smoking complains of shortness of breath and persistent cough over the past 8 months. He reveals that in the 1960s he worked for several years as a boiler operator. Chest X-ray shows diffuse lung infiltrates. Which of the following is the most probable cause of these findings?
Your Answer: Silicosis
Correct Answer: Asbestosis
Explanation:Asbestosis is a chronic lung disease which leads to long-term respiratory complications and is caused by the inhalation of asbestos fibres. Symptoms due to long exposure to asbestos usually appear 10 to 40 years after initial exposure and include shortness of breath, cough, weight loss, clubbing of the fingers and chest pain. Typical chest X-ray findings include diffuse lung infiltrates that cause the appearance of shaggy heart borders.
-
This question is part of the following fields:
- Pathology
- Respiratory
-
-
Question 83
Correct
-
Identify which of the following muscles acts on two joints?
Your Answer: Sartorius
Explanation:The sartorius muscle, the longest muscle in the body, is one of the two jointed or biarticular muscles. It originates from the anterior superior iliac spine and part of the notch between the anterior superior iliac spine and anterior inferior iliac spine and crosses both the hip joint and the knee joint. At the hip joint the sartorius flexes and rotates the thigh at the hip joint and flexes the leg at the knee joint.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 84
Incorrect
-
A cell is classified on the basis of its regenerative ability. Which of the following cells represent a permanent cell?
Your Answer: Osteocyte
Correct Answer: Erythrocyte
Explanation:An erythrocyte is the last cell in the progeny of RBC cell division and is not capable of further division and regeneration. Hepatocytes, osteocytes and epithelium of kidney tubules are all stable cells. Colonic mucosa and pluripotent hematopoietic stem cells are all labile cells.
-
This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
-
-
Question 85
Correct
-
Skin infiltration by neoplastic T lymphocytes is seen in:
Your Answer: Mycosis fungoides
Explanation:Mycosis fungoides is a chronic T-cell lymphoma that involves the skin and less commonly, the internal organs such as nodes, liver, spleen and lungs. It is usually diagnosed in patients above 50 years and the average life expectancy is 7-10 years. It is insidious in onset and presents as a chronic, itchy rash, eventually spreading to involve most of the skin. Lesions are commonly plaque-like, but can be nodular or ulcerated. Symptoms include fever, night sweats and weight loss. Skin biopsy is diagnostic. However, early cases may pose a challenge due to fewer lymphoma cells. The malignant cells are mature T cells (T4+, T11+, T12+). The epidermis shows presence of characteristic Pautrier’s micro abscesses are present in the epidermis.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 86
Incorrect
-
During a laparoscopic surgery, the surgeon visualizes the medical umbilical folds on the deep surface of the anterior abdominal wall. What causes the medial umbilical folds?
Your Answer: Obliterated umbilical veins
Correct Answer: Obliterated umbilical arteries
Explanation:The medial umbilical ligament is a structure found on the deep surface of the anterior abdominal wall and is covered by the medial umbilical folds. It is a paired structure that represents the remnants of the fetal umbilical artery. They have no role in humans after birth other than to be used as a landmark for exploring the medial inguinal fossa during laparoscopic inguinal hernia repair.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 87
Correct
-
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.
-
This question is part of the following fields:
- Anatomy
- Pelvis
-
-
Question 88
Correct
-
The line which divides the perineum into two triangles is connected to the?
Your Answer: Ischial tuberosities
Explanation:The perineum has it’s deep boundaries in front of the pubic arch and the arcuate ligament of the pubis, behind the tip of the coccyx and on either side of the inferior rami of the pubis and ischium and the sacrotuberous ligament. It also corresponds to the outlet of the pelvis. A line drawn transversely across, in front of the ischial tuberosities divides the space into two portions, the posterior contains the termination of the anal canal and the anterior, contains the external urogenital organs.
-
This question is part of the following fields:
- Anatomy
- Pelvis
-
-
Question 89
Correct
-
Hormones of the anterior pituitary include which of the following?
Your Answer: Prolactin
Explanation:The anterior pituitary gland (adenohypophysis or pars distalis) synthesizes and secretes:
1. FSH (follicle-stimulating hormone)
2. LH (luteinizing hormone)
3. Growth hormone
4. Prolactin
5. ACTH (adrenocorticotropic hormone)
6. TSH (thyroid-stimulating hormone).
The posterior pituitary gland (neurohypophysis) stores and secretes 2 hormones produced by the hypothalamus:
1. ADH (antidiuretic hormone or vasopressin)
2. Oxytocin
-
This question is part of the following fields:
- Endocrine
- Physiology
-
-
Question 90
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
-
This question is part of the following fields:
- Anatomy
- Pelvis
-
-
Question 91
Correct
-
The annular ligament in the forearm:
Your Answer: Encircles the head of the radius
Explanation:The annular ligament forms about four-fifths of the osseofibrous ring and is attached to the anterior and posterior margins of the radial notch. It is a strong band of fibres which encircles the head of the radius retaining it in contact with the radial notch of the ulna. When it comes to its upper border, it blends with the anterior and posterior ligament of the elbow.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 92
Correct
-
An intern is attempting to put in an arterial line in an ICU patients left foot. Which is the best site to feel for the pulsation of the dorsalis pedis artery in the foot?
Your Answer: Just lateral to the tendon of extensor hallucis longus
Explanation:The dorsalis pedis artery is the continuation of the anterior tibial artery. The pulse of the posterior tibial artery, which comes from the posterior compartment of the leg, may be felt behind the medial malleolus just lateral to the tendon of the extensor hallucis longus.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 93
Incorrect
-
Intravenous diazepam was administered to a man who was brought to the emergency department with status epilepticus. He was administered 15 l/min oxygen via a reservoir bag mask. Blood investigations showed sodium = 140 mmol/l, potassium = 4 mmol/l and chloride = 98 mmol/l. His arterial blood gas analysis revealed pH 7.08, p(CO2)= 61.5 mmHg, p(O2) = 111 mmHg and standard bicarbonate = 17 mmol/l. This patient had:
Your Answer: Metabolic acidosis
Correct Answer: Mixed acidosis
Explanation:Acidosis with high p(CO2) and low standard bicarbonate indicates mixed acidosis. Lower p(O2) is due to breathing of 70% oxygen. The prolonged seizures lead to lactic acidosis and the intravenous diazepam is responsible for the respiratory acidosis. Treatment includes airway manoeuvres and oxygen, assisted ventilation if needed, and treatment with fluids.
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 94
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.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 95
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 96
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.
-
This question is part of the following fields:
- Microbiology
- Pathology
-
-
Question 97
Correct
-
Which of the following is involved in vitamin B12 absorption?
Your Answer: Intrinsic factor
Explanation:Absorption of vitamin B12 is by an active transport process and occurs in the ileum. Most cobalamins are bound to proteins and are released in the stomach due to low pH and pepsin. The cobalamins then bind to R proteins, i.e. haptocorrin (HC) secreted from salivary glands and gastric juice. Another cobalamin binding protein is Intrinsic factor (IF) secreted from the gastric parietal cells. The cobalamin-HC complex is digested by pancreatic proteases in the intestinal lumen, and the free cobalamin then binds to IF. The complex then reaches a transmembrane receptor in the ileum and undergoes endocytosis. Cobalamin is then released intracellularly and binds to transcobalamin II (TC II). The newly formed complex then exits the ileal cell and enters the blood circulation.
-
This question is part of the following fields:
- Gastroenterology
- Physiology
-
-
Question 98
Incorrect
-
The muscle that stabilizes the stapes is innervated by which of the following nerves?
Your Answer: Cranial nerve VIII
Correct Answer: Facial nerve
Explanation:The stapedius is the smallest skeletal muscle in the human body. At just over one millimetre in length, its purpose is to stabilize the smallest bone in the body, the stapes and is innervated by a branch of the facial nerve.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 99
Incorrect
-
In relation to the muscles of facial expression, It is true to say:
Your Answer: Some muscles of facial expression receive their motor supply via the zygomaticofacial nerve
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.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 100
Incorrect
-
Work of breathing (WOB) is the energy expended to inhale and exhale a breathing gas. Normally, maximal amount of work of breathing is required to overcome:
Your Answer: Inertia
Correct Answer: Elastic lung compliance
Explanation:The forces of elastance (compliance), frictional resistance and inertia have been identified as the forces that oppose lung inflation and deflation. The normal relaxed state of the lung and chest is partially empty. Further exhalation requires muscular work. Inhalation is an active process requiring work. About 60–66% of the total work performed by the respiratory muscles is used to overcome the elastic or compliance characteristics of the lung–chest cage, 30–35% is used to overcome frictional resistance and only 2–5% of the work is used for inertia.
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 101
Incorrect
-
A 60-year-old woman complains of left sided headaches which have been recurring for several years. She recently suffered from a focal seizure for the first time a few days ago. A CT scan shows a mass in the left hemisphere of the brain. The most likely diagnosis is:
Your Answer: Glioblastoma multiforme
Correct Answer: Meningioma
Explanation:Meningiomas are a common benign intracranial tumour, and their incidence is higher in women between the ages of 40-60 years old. Many of these tumours are asymptomatic and are diagnosed incidentally, although some of them may have malignant presentations (less than 2% of cases). These benign tumours can develop wherever there is dura, over the convexities near the venous sinuses, along the base of the skull, in the posterior fossa and, within the ventricles.
-
This question is part of the following fields:
- Neurology
- Pathology
-
-
Question 102
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.
-
This question is part of the following fields:
- Neoplasia
- Pathology
-
-
Question 103
Correct
-
A 16-year old boy was brought in an unconscious state to the emergency department. Clinical evaluation pointed in favour of acute adrenal insufficiency. On enquiry, it was revealed that he was suffering from a high grade fever 24 hours prior. On examination, extensive purpura were noted on his skin. The likely diagnosis is:
Your Answer: Meningococcaemia
Explanation:Findings described are suggestive of Waterhouse-Friderichsen syndrome which develops secondary to meningococcaemia. The reported incidence of Addison’s disease is 4 in 100,000. It affects both sexes equally and is seen in all age groups. It tends to show clinical symptoms at the time of metabolic stress or trauma. The symptoms are precipitated by acute infections, trauma, surgery or sodium loss due to excessive perspiration.
-
This question is part of the following fields:
- Endocrine
- Pathology
-
-
Question 104
Correct
-
After a car accident, a 30-year-old woman is alert and only has minor, superficial injuries. 2 hours later, she becomes unconscious and a CT scan reveals a convex, lens-shaped haemorrhage over the right parietal region. The most likely diagnosis is:
Your Answer: Epidural haematoma
Explanation:Epidural haematomas are usually caused by arterial bleeding, classically due to damage to the middle meningeal artery by a temporal bone fracture. Symptoms develop within minutes to several hours after the injury and consist of increasing headache, decreased level of consciousness, hemiparesis and pupillary dilation with loss of light reactivity. Around 15–20% of epidural hematomas are fatal.
-
This question is part of the following fields:
- Neurology
- Pathology
-
-
Question 105
Correct
-
Hepatomegaly with greatly increased serum alpha-fetoprotein is seen in which of the following conditions?
Your Answer: Hepatocellular carcinoma
Explanation:Hepatocellular carcinoma or hepatoma affects people with pre-existing cirrhosis and is more common in areas with higher prevalence of hepatitis B and C. Diagnosis include raise alpha-fetoprotein levels, imaging and liver biopsy if needed. Patients at high-risk for developing this disease can undergo screening by periodic AFP measurement and abdominal ultrasonography. The malignancy carries poor prognosis (see also Answer to 10.4).
-
This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
-
-
Question 106
Correct
-
A 16 year old girl fractured a bone in her left foot. Upon examination the clinician discovered that the fracture affected the insertion of the peroneus brevis muscle. Which of the following bones was most likely affected?
Your Answer: Base of the fifth metatarsal
Explanation:The peroneus brevis muscle originates from the lower two-thirds of the lateral body of the fibula and has inserts at the base of the fifth metatarsal. Fractures to this bone are common and can be due to infection, trauma, overuse and repetitive use.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 107
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 108
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 109
Incorrect
-
From which of the following cells is heparin produced?
Your Answer: Hepatocytes
Correct Answer: Mast cells
Explanation:Heparin is a natural highly-sulphated glycosaminoglycan that has anticoagulant functions. It is produced by the body basophils and mast cells.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 110
Correct
-
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.
-
This question is part of the following fields:
- General
- Physiology
-
-
Question 111
Correct
-
The periphery of a haematoma is infiltrated by fibroblasts, collagen and new vasculature. This process is best described as?
Your Answer: Organisation of the haematoma
Explanation:Formation of granulation tissue at the periphery of the hematoma is a normal process leading to resolution. This granulation tissue is composed of new capillaries, fibroblasts and collagen. Lysis of a blood clot can occur, but the actual process of this response is known as organization, wherein the scar tissue will become part of the vessels. This is followed by recanalization and embolization which can lead to eventual complications. Proliferation of a clot will occur due to an imbalance in the clotting and lysing systems. Thrombosis has nothing to do with the process described above.
-
This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
-
-
Question 112
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 113
Incorrect
-
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: Acute interstitial nephritis
Correct 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.
-
This question is part of the following fields:
- Pathology
- Renal
-
-
Question 114
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 115
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: L5, S1
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 116
Incorrect
-
Cranial nerve XII, the hypoglossal nerve, innervates which one of the following muscles in the list?
Your Answer: Palatoglossus
Correct Answer: Hyoglossus
Explanation:The cranial nerve XII, hypoglossal nerve, innervates all the intrinsic and extrinsic muscles of the tongue except the palatoglossus. The muscles of the tongue innervated by this nerve include the extrinsic muscles; hyoglossus, styloglossus, genioglossus and the intrinsic muscles; superior longitudinal, inferior longitudinal, vertical and transverse muscles. The salpingopharyngeus, palatoglossus and the palatopharyngeus muscles are innervated by the vagus nerve. The stylopharyngeus muscle is innervated by the glossopharyngeal nerve (CN IX). The mylohyoid muscle is innervated by the inferior alveolar nerve, a branch of the mandibular nerve. Finally, the geniohyoid muscle is innervated by the olfactory nerve (CN I) via the hypoglossal nerve.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 117
Correct
-
Which muscles are attached to the tibial tuberosity?
Your Answer: Vastus intermedius
Explanation:The tuberosity of the tibia is the site of attachment to the ligamentum patella (the tendon of the quadriceps femoris muscle which include four heads: rectus femoris, vastus medialis, intermedius and lateralis).
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 118
Incorrect
-
As per the Poiseuille-Hagen formula, doubling the diameter of a vessel will change the resistance of the vessel from 16 peripheral resistance units (PRU) to:
Your Answer: 32 PRU
Correct Answer: 1 PRU
Explanation:Poiseuille-Hagen formula for flow in along narrow tube states that F = (PA– PB) × (Π/8) × (1/η) × (r4/l) where F = flow, PA– PB = pressure difference between the two ends of the tube, η = viscosity, r = radius of tube and L = length of tube. Also, flow is given by pressure difference divided by resistance. Hence, R = 8ηL ÷ Πr4. Hence, the resistance of the vessel changes in inverse proportion to the fourth power of the diameter. So, if the diameter of the vessel is increased to twice the original, it will lead to decrease in resistance to one-sixteenth its initial value.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 119
Correct
-
Acute respiratory distress syndrome (ARDS) is a medical condition that occurs in critically ill patients, and can be triggered by events such as trauma and sepsis. Which of the following variables is most likely to be lower than normal in a patient with ARDS?
Your Answer: Lung compliance
Explanation:Acute (or Adult) respiratory distress syndrome (ARDS) is a medical condition occurring in critically ill patients characterized by widespread inflammation in the lungs. The development of acute respiratory distress syndrome (ARDS) starts with damage to the alveolar epithelium and vascular endothelium, resulting in increased permeability to plasma and inflammatory cells. These cells pass into the interstitium and alveolar space, resulting in pulmonary oedema. Damage to the surfactant-producing type II cells and the presence of protein-rich fluid in the alveolar space disrupt the production and function of pulmonary surfactant, leading to micro atelectasis and impaired gas exchange. The pathophysiological consequences of lung oedema in ARDS include a decrease in lung volumes, compliance and large intrapulmonary shunts. ARDS may be seen in the setting of pneumonia, sepsis, following trauma, multiple blood transfusions, severe burns, severe pancreatitis, near-drowning, drug reactions, or inhalation injuries.
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 120
Incorrect
-
Which of these structures is most likely to be damaged if a patient loses consciousness days or weeks after an otherwise insignificant head trauma, especially in elderly patients?
Your Answer: Middle meningeal artery
Correct Answer: Dural bridging vein
Explanation:A subdural haematoma is a type of hematoma, usually associated with traumatic brain injury, in which blood collects between the dura mater and the pia-arachnoid mater. Symptoms of subdural haemorrhage have a slower onset than those of epidural haemorrhages because the lower pressure veins bleed more slowly than arteries. These injuries are more common in elderly patients, especially those taking antiplatelet or anticoagulant drugs. Oedema and increased intracranial pressure are unusual.
-
This question is part of the following fields:
- Neurology
- Pathology
-
SESSION STATS - PERFORMANCE PER SPECIALTY
