-
Question 1
Correct
-
Question 2
Incorrect
-
Which of the following clinical features is NOT a typical feature of haemolytic anaemias:
Your Answer: Leg ulcers
Correct Answer: Angular cheilitis
Explanation:Features include:
Anaemia
Jaundice (caused by unconjugated bilirubin in plasma, bilirubin is absent from urine)
Pigment gallstones
Splenomegaly
Ankle ulcers
Expansion of marrow with, in children, bone expansion e.g. frontal bossing in beta-thalassaemia major
Aplastic crisis caused by parvovirus -
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 3
Incorrect
-
A patient is complaining of painless jaundice. His bilirubin levels are abnormally high.
Which of the following statements about bile is correct?Your Answer: It helps to reduce the surface area of fat
Correct Answer: Bile acids are amphipathic
Explanation:The liver produces bile on a constant basis, which is then stored and concentrated in the gallbladder. In a 24-hour period, around 400 to 800 mL of bile is generated.
Bile is involved in the following processes:
Fats are broken down into fatty acids.
Waste products are eliminated.
Cholesterol homeostasis is the balance of cholesterol in the body.The enteric hormones cholecystokinin and secretin are primarily responsible for bile secretion. When chyme from an unprocessed meal enters the small intestine, they are released, and they play the following function in bile secretion and flow:
Cholecystokinin promotes gallbladder and common bile duct contractions, allowing bile to reach the intestine.
Secretin enhances the secretion of bicarbonate and water by biliary duct cells, increasing the amount of bile and its flow into the gut.Bile acids have a hydrophobic and hydrophilic area, making them amphipathic. Bile acids’ amphipathic nature allows them to perform the following crucial functions:
Emulsification of lipid aggregates increases the surface area of fat and makes it easier for lipases to digest it.
Lipid solubilization and transport: solubilizes lipids by creating micelles, which are lipid clumps that float in water. -
This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
-
-
Question 4
Incorrect
-
Parathyroid hormone is released by which of the following:
Your Answer: Parafollicular cells of the thyroid gland
Correct Answer: Chief cells of the parathyroid gland
Explanation:Parathyroid hormone (PTH) is a peptide hormone synthesised by the chief cells of the parathyroid glands, located immediately behind the thyroid gland. PTH is primarily released in response to decreasing plasma [Ca2+] concentration. PTH acts to increase plasma calcium levels and decrease plasma phosphate levels.
Parathyroid hormone (PTH) acts to increase calcium reabsorption in the distal tubule of the nephron (by activating Ca2+entry channels in the apical membrane and the Ca2+ATPase pump in the basolateral membrane) and increase phosphate excretion by inhibiting reabsorption in the proximal tubule of the nephron. -
This question is part of the following fields:
- Endocrine
- Physiology
-
-
Question 5
Incorrect
-
Question 6
Correct
-
Your consultant requests that you do a lumbar puncture on a patient who is suspected of having meningitis. This patient, a 15-year-old female, presented to the emergency department with a fever, headache, and neck stiffness. Where should you aspirate a sample of CSF?
Your Answer: Subarachnoid space
Explanation:A lumbar puncture, also known as a spinal tap, is a procedure that involves inserting a needle into the lower back’s lumbar region.
A needle is inserted into the space between the arachnoid mater and the pia mater, also known as the subarachnoid space, to remove a sample of cerebrospinal fluid.
-
This question is part of the following fields:
- Anatomy
- Head And Neck
-
-
Question 7
Incorrect
-
The least likely feature expected to be seen in a lesion of the frontal lobe is which of the following?
Your Answer: Conjugate eye deviation towards side of lesion
Correct Answer: Loss of two-point discrimination
Explanation:Lesions in different areas give rise to different symptoms.
Lesions of the parietal lobe give rise to loss of two-point discrimination.
Lesions to Broca’s area give rise to expressive dysphasia results from damage
Lesions to the primary motor cortex give rise to contralateral weakness of the face and arm.
Lesions to the prefrontal cortex give rise to personality change.
Lesions to the frontal eye field give rise to conjugate eye deviation towards side of lesion. -
This question is part of the following fields:
- Anatomy
- Central Nervous System
-
-
Question 8
Incorrect
-
A 25 year old man presents to the emergency room with abdominal pain, vomiting and constipation. A CT scan is done which is suggestive of Meckel's diverticulum. Where does the blood supply of the Meckel's diverticulum originate?
Your Answer: Superior pancreaticoduodenal artery
Correct Answer: Superior mesenteric artery
Explanation:Meckel’s diverticulum has certain classic characteristics.
1. It lies on the antimesenteric border of the middle-to-distal ileum
2. It is approximately 2 feet proximal to the ileocaecal junction
3. It appears as a blind-ended tubular outpouching of bowel
4. It is about 2 inches long,
5. It occurs in about 2% of the population,
6. It may contain two types of ectopic tissue (gastric and pancreatic).
7. The diverticulum is supplied by the superior mesenteric artery.
8. Proximal to the major duodenal papilla the duodenum is supplied by the gastroduodenal artery (branch of the coeliac trunk)
9. Distal to the major duodenal papilla it is supplied by the inferior pancreaticoduodenal artery (branch of superior mesenteric artery).
10. The arterial supply to the jejunoileum is from the superior mesenteric artery. -
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 9
Incorrect
-
Identify the type of graph described below:
A graph that is a useful summary of a set of bivariate data (two variables), usually drawn before working out a linear correlation coefficient or fitting a regression line.Your Answer: Forest plot
Correct Answer: Scatterplot
Explanation:A scatterplot is a useful summary of a set of bivariate data (two variables), usually drawn before working out a linear correlation coefficient or fitting a regression line. It gives a good visual picture of the relationship between the two variables, and aids the interpretation of the correlation coefficient or regression model. Each unit contributes one point to the scatterplot, on which points are plotted but not joined. The resulting pattern indicates the type and strength of the relationship between the two variables.
-
This question is part of the following fields:
- Evidence Based Medicine
-
-
Question 10
Incorrect
-
A 20-year-old male has an anaphylactic reaction following a wasp sting.
What type of hypersensitivity reaction is this?
Your Answer: Type IV
Correct Answer: Type I
Explanation:Anaphylaxis is an example of a type I hypersensitivity reaction.
It is IgE mediated.
It requires a prior exposure to the antigen. The initial exposure sensitizes the body to the antigen and a second exposure to that antigen leads to an anaphylactic reaction.
Massive calcium influx into the cells leads to mast cell degranulation.
The Immunoglobulin antigen complex binds to Fc receptors on the surface of mast cells. The result is mast cell degranulation and release of histamine, proteoglycans and serum proteases from cytoplasmic granules.
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 11
Correct
-
In a patient with an ongoing seizure, after what time period should treatment be commenced?
Your Answer: 5 minutes
Explanation:Immediate emergency care and treatment should be given to children, young people and adults who have prolonged or repeated convulsive seizures.
Prolonged seizures last 5 minutes or more.
Repeated seizures refer to 3 or more seizures in an hour. -
This question is part of the following fields:
- Central Nervous System
- Pharmacology
-
-
Question 12
Incorrect
-
Regarding calcium handling by the kidneys, which of the following statements is CORRECT:
Your Answer: About 50% of filtered Ca 2+ is reabsorbed passively in the loop of Henle.
Correct Answer: Activated vitamin D upregulates Ca 2+ ATPase pumps in the distal tubule.
Explanation:Calcium that is not protein bound is freely filtered in the glomerulus, and there is reabsorption along the nephron.About 70% is reabsorbed in the proximal tubule.About 20% is reabsorbed in the thick ascending limb of the loop of Henle.This reabsorption is mainly passive and paracellular and driven by sodium reabsorption. Sodium reabsorption causes water reabsorption, which raises tubular calcium concentration, causing calcium to diffuse out of the tubules. The positive lumen potential also encourages calcium to leave the tubule.About 5 – 10% is reabsorbed in the distal convoluted tubule.Less than 0.5% is reabsorbed in the collecting ducts.Calcium reabsorption in the distal nephron is active and transcellular and is the major target for hormonal control.Calcium homeostasis is primarily controlled by three hormones: parathyroid hormone, activated vitamin D and calcitonin.Parathyroid hormone acts on the kidneys to increase calcium reabsorption in the distal tubule by activating Ca2+entry channels in the apical membrane and the Ca2+ATPase pump in the basolateral membrane (and to decrease phosphate reabsorption in the proximal tubule).Activated vitamin D acts to increase calcium reabsorption in the distal tubule via activation of a basolateral Ca2+ATPase pump (and to increase phosphate reabsorption).Calcitonin acts to inhibit renal reabsorption of calcium (and phosphate).
-
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 13
Incorrect
-
An 8-year-old boy was brought to the emergency room with complaints of a rash and fever that have been present for the past 3 days. Upon history taking and observation, it was noted that the rash started behind the ears and then spread to the face and body. The presence of coryzal symptoms, dry cough, and conjunctivitis was also observed.
What is most likely the diagnosis of the case presented above?Your Answer: Kawasaki disease
Correct Answer: Measles
Explanation:The measles virus is an enveloped virus classified in the genus
Morbillivirus.
Measles is highly contagious and spreads by aerosol. Initial replication takes place in the mucosal cells of the respiratory tract; measles virus then replicates in the local lymph nodes and spreads systemically. The virus circulates in the T and B cells and monocytes, until eventually the lungs, gut, bile duct, bladder, skin, and lymphatic organs are involved. After an incubation period of 7 to 10 days, there is an abrupt onset, with symptoms of sneezing, runny nose and cough, red eyes, and rapidly rising fever. About 2 to 3 days later, a maculopapular rash appears on the head and trunk. Koplik spots, lesions on the oral mucosa consisting of irregular red spots, with a bluish white speck in the centre, generally appear 2 to 3 days before the rash and are diagnostic.Measles is easily diagnosed clinically, so few requests for laboratory identification are made. The virus is fragile and must be handled carefully. The specimens of choice are from the nasopharynx and urine, but the virus can only be recovered from these sources in the early stages of infection. The virus grows on PMK cells, causing the formation of distinctive spindle-shaped or multinucleated cells.
-
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 14
Correct
-
An analytical cohort study is done to compare the relationship between omega 3 intake and occurrence of myocardial infarction (MI) among males aged over 65 years. The following are the data from the study:
No. of subjects taking placebo: 100 men
No. of subjects taking placebo who suffered an MI: 15 men
No. of subjects taking omega 3: 100 men
No. of subjects taking omega 3 who suffered an MI: 5 men
Compute for the absolute risk in the treatment (omega 3) group.Your Answer: 0.05
Explanation:The absolute risk (AR) is the probability or chance of an event. It is computed as the number of events in treated or control groups, divided by the number of people in that group.
AR = 5/100 = 0.05
-
This question is part of the following fields:
- Evidence Based Medicine
-
-
Question 15
Incorrect
-
Regarding renal clearance, which of the following statements is CORRECT:
Your Answer: Calculating clearance of a substance is routinely used in clinical practice to calculate the GFR.
Correct Answer: The MDRD equation uses plasma creatinine to estimate the GFR making an adjustment for age, sex and race.
Explanation:Clearance is defined as the volume of plasma that is cleared of a substance per unit time. Inulin clearance is the gold standard for measurement of GFR but creatinine clearance is typically used instead. Creatinine is freely filtered and not reabsorbed, but there is a little creatinine tubular secretion. In practice, GFR is usually estimated from the plasma creatinine using a formula e.g. the MDRD equation making an adjustment for age, sex and race.
-
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 16
Incorrect
-
A 60-year-old man presents with marked breathlessness. He has with a history of ischaemic heart disease. On examination, there is coarse bibasal crackles, marked peripheral oedema and chest X-ray taken is consistent with severe pulmonary oedema. RR is 28 per minute.
Which receptor is responsible for detecting pulmonary oedema and the subsequent increase in respiratory rate?Your Answer: Atrial volume receptors
Correct Answer: Juxtacapillary receptors
Explanation:Pulmonary oedema causes stimulation of the Juxtacapillary receptors (J receptors) leading to a reflex increase in breathing rate. These receptors are also thought to be involved in the sensation of dyspnoea. The J receptors are sensory cells and are located within the alveolar walls in juxtaposition to the pulmonary capillaries.
Aortic baroreceptor are involved in detecting blood pressure
Central chemoreceptors detect changes in CO2 and hydrogen ion within the brain
Atrial volume receptors regulate plasma volume
-
This question is part of the following fields:
- Physiology
- Respiratory Physiology
-
-
Question 17
Incorrect
-
Regarding shingles, which of the following statements is CORRECT:
Your Answer: Topical antiviral treatment is recommended in shingles.
Correct Answer: You can catch chickenpox from a patient with shingles.
Explanation:After primary infection, VZV remains latent in sensory ganglia and in about 20% of patients will reactivate resulting in shingles, a painful vesicular rash in the related dermatome. Shingles usually affects older people and the immunocompromised. Shingles lesions are infectious to non-immune individuals who are at risk of developing chickenpox. Shingles can not be contracted directly from chickenpox, or from other cases of shingles. Shingles is treated with systemic antiviral treatment to reduce the severity and duration of pain, reduce complications, and reduce viral shedding.
-
This question is part of the following fields:
- Microbiology
- Pathogens
-
-
Question 18
Incorrect
-
On her most recent blood tests, a 55 year-old female with a history of hypertension was discovered to be hypokalaemic. She  is diagnosed with primary hyperaldosteronism.
Which of the following is a direct action of aldosterone?
Your Answer: Secretion of Cl - into the distal convoluted tubule
Correct Answer: Secretion of H + into the distal convoluted tubule
Explanation:Aldosterone is a steroid hormone produced in the adrenal cortex’s zona glomerulosa. It is the most important mineralocorticoid hormone in the control of blood pressure. It does so primarily by promoting the synthesis of Na+/K+ATPases and the insertion of more Na+/K+ATPases into the basolateral membrane of the nephron’s distal tubules and collecting ducts, as well as stimulating apical sodium and potassium channel activity, resulting in increased sodium reabsorption and potassium secretion. This results in sodium conservation, potassium secretion, water retention, and a rise in blood volume and blood pressure.
Aldosterone is produced in response to the following stimuli:
Angiotensin II levels have risen.
Potassium levels have increased.
ACTH levels have risen.
Aldosterone’s principal actions are as follows:
Na+ reabsorption from the convoluted tubule’s distal end
Water resorption from the distal convoluted tubule (followed by Na+)
Cl is reabsorbed from the distal convoluted tubule.
K+ secretion into the convoluted distal tubule’sÂ
H+ secretion into the convoluted distal tubule’s -
This question is part of the following fields:
- Physiology
- Renal Physiology
-
-
Question 19
Incorrect
-
Regarding drug interactions with erythromycin, which of the following statements is INCORRECT:
Your Answer: There is an increased risk of myopathy if erythromycin is taken with simvastatin.
Correct Answer: Erythromycin decreases plasma levels of warfarin.
Explanation:Erythromycin and clarithromycin inhibit cytochrome P450-mediated metabolism of warfarin, phenytoin and carbamazepine and may lead to accumulation of these drugs. There is an increased risk of myopathy (due to cytochrome P450 enzyme CYP3A4 inhibition) if erythromycin or clarithromycin is taken with atorvastatin or simvastatin. Erythromycin increases plasma concentrations of theophylline, and theophylline may also reduce absorption of oral erythromycin. All macrolides can prolong the QT-interval and concomitant use of drugs that prolong the QT interval is not recommended.
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 20
Incorrect
-
Regarding dynamic compression of the airways, which of the following statements is CORRECT:
Your Answer: It does not occur in normal expiration, because the intrapleural pressure is positive throughout.
Correct Answer: It occurs during forced expiration.
Explanation:Dynamic compression occurs because as the expiratory muscles contract during forced expiration, all the structures within the lungs, including the airways, are compressed by the positive intrapleural pressure. Consequently the smaller airways collapse before the alveoli empty completely and some air remains within the lungs (the residual volume). Physiologically this is important as a completely deflated lung with collapsed alveoli requires significantly more energy to inflate. Dynamic compression does not occur in normal expiration because the intrapleural pressure is negative throughout the whole cycle.
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 21
Correct
-
Beta cells of the endocrine pancreas produce which of the following hormones:
Your Answer: Insulin
Explanation:Insulin is produced by beta cells, located centrally within the islets of Langerhans, in the endocrine tissues of the pancreas. Insulin is a polypeptide hormone consisting of two short chains (A and B) linked by disulphide bonds. Proinsulin is synthesised as a single-chain peptide. Within storage granules, a connecting peptide (C peptide) is removed by proteases to yield insulin. Insulin release is stimulated initially during eating by the parasympathetic nervous system and gut hormones such as secretin, but most output is driven by the rise in plasma glucose concentration that occurs after a meal. The effects of insulin are mediated by the receptor tyrosine kinase.
-
This question is part of the following fields:
- Endocrine
- Physiology
-
-
Question 22
Incorrect
-
Which of the following is the most abundant immunoglobulin in plasma:
Your Answer: IgA
Correct Answer: IgG
Explanation:IgA is the major Ig in secretions, particularly from the gastrointestinal tract (but also in saliva, tears, sweat and breast milk).
IgE is important for mast cell degranulation in allergic and antiparasitic response. In the allergic response, the plasma cell produces IgE-antibodies, which, like antibodies of other immunoglobulin isotypes, are capable of binding a specific allergen via its Fab portion.
IgG is the most abundant in plasma (comprising 80% of normal serum immunoglobulin) and the main circulatory Ig for the secondary immune response. -
This question is part of the following fields:
- Immune Responses
- Pathology
-
-
Question 23
Incorrect
-
Question 24
Incorrect
-
Which of the following does NOT predispose to digoxin toxicity in a patient taking digoxin:
Your Answer:
Correct Answer: Hyponatraemia
Explanation:Hypoxia, hypercalcaemia, hypokalaemia and hypomagnesaemia predispose to digoxin toxicity. Care should also be taken in the elderly who are particularly susceptible to digoxin toxicity. Hypokalaemia may be precipitated by use of diuretics. Although hyponatremia can result in the development of other pathological disturbances, it does not potentiate digoxin toxicity.
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 25
Incorrect
-
You are giving a presentation on the immune system as part of your peer-to-peer teaching sessions. Yu are currently discussing phagocytes. Macrophages are derived from which of the following cells:
Your Answer:
Correct Answer: Monocytes
Explanation:Monocytes spend only a short time in the marrow and, after circulating for 20-40 hours, leave the blood to enter the tissues where they become macrophages. Macrophages form the reticuloendothelial system in the liver, spleen and lymph nodes. The lifespan of macrophages may be as long as several months or even years. In tissues the macrophages become self-replicating without replenishment from the blood. They assume specific functions in different tissues e.g. dendritic cells which are involved in antigen presentation to T-cells. Macrophages may be activated by cytokines such as IFN-gamma, contact with complement or direct contact with the target cell through leucocyte adhesion molecules.
-
This question is part of the following fields:
- Immune Responses
- Pathology
-
-
Question 26
Incorrect
-
A 57-year-old male presents to the orthopaedic clinic complaining of pain and swelling in the left knee joint. On examination, the left knee is swollen, tender and erythematous. The patient is booked for joint aspiration, and a diagnosis of pseudogout is made following the aspiration.
Which types of crystals would be seen in the joint aspirate to lead to this diagnosis?Your Answer:
Correct Answer: Positively birefringent brick-shaped crystals
Explanation:Gout and pseudogout are both characterised by crystal deposition in the affected joints. The deposition of urate crystals causes gout, while calcium pyrophosphate crystals cause pseudogout. The crystals can be distinguished microscopically because urate crystals are negatively birefringent needle-shaped crystals, whilst calcium pyrophosphate crystals are positively birefringent brick-shaped crystals.
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 27
Incorrect
-
A 53 year old male is found to have megaloblastic anaemia secondary to folate deficiency. He has a known history of alcohol abuse. Which of the following is characteristic of this condition?
Your Answer:
Correct Answer: Increased mean corpuscular volume (MCV)
Explanation:Megaloblastic anaemia occurs when there is inhibition of DNA synthesis as red blood cells are produced. Impairment of DNA synthesis causes the cell cycle to be unable to progress from the growth stage to the mitosis stage. As a result, there is continuous cell growth without division, with an increase in mean corpuscular volume (MCV), which presents as macrocytosis. The most common cause of this defect in red cell DNA synthesis is hypovitaminosis, in particular, vitamin B12 deficiency or folate deficiency.
Folate is an essential vitamin that can be found in most foods, and is highest in liver, green vegetables and yeast. 200 – 250 μg is found in the normal daily diet, and about 50% is absorbed. The daily adult requirement is about 100 μg and its absorption is principally from the duodenum and jejunum. Folate stores are normally only adequate for 4 months and so clinical features of folate deficiency usually become evident after this time. -
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 28
Incorrect
-
Surface area of the absorptive surface in the small intestine is increased by all but which of the following:
Your Answer:
Correct Answer: Teniae coli
Explanation:Factors increasing the surface area include:The small intestine is very long – about 5 m in length.The inner wall of the small intestine is covered by numerous folds of mucous membrane called plicae circulares.The lining of the small intestine is folded into many finger-like projections called villi.The surface of the villi is covered with a layer of epithelial cells which, in turn, have many small projections called microvilli that project towards the lumen of the intestine (forming the brush border).
-
This question is part of the following fields:
- Gastrointestinal
- Physiology
-
-
Question 29
Incorrect
-
A tumour compresses the jugular foramen of a 50-year-old patient. Compression of several nerves in the jugular foramen will result in which of the following complications?
Your Answer:
Correct Answer: Loss of gag reflex
Explanation:The glossopharyngeal nerve, which is responsible for the afferent pathway of the gag reflex, the vagus nerve, which is responsible for the efferent pathway of the gag reflex, and the spinal accessory nerve all exit the skull through the jugular foramen. These nerves are most frequently affected if the jugular foramen is compressed. As a result, the patient’s gag reflex is impaired.
The vestibulocochlear nerve is primarily responsible for hearing. The trigeminal nerve provides sensation in the face. The facial nerve innervates the muscles of face expression (including those responsible for closing the eye). Tongue motions are controlled mostly by the hypoglossal nerve.
-
This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
-
-
Question 30
Incorrect
-
A 12-year old boy is taken to the emergency room after accidentally falling off the monkey bars. Witnesses of the accident reported that, when the patient fell, he hit his right hand on a bar and a loud thump was heard. On examination, the hand is oedematous, tender and erythematous. On ultrasound, a rupture of the flexor carpi ulnaris is noted.
Which of the following statements is true regarding the flexor carpi ulnaris?Your Answer:
Correct Answer: It acts to adduct the hand at the wrist joint
Explanation:Flexor carpi ulnaris is a fusiform muscle located in the anterior compartment of the forearm. It belongs to the superficial flexors of the forearm, along with pronator teres, palmaris longus, flexor digitorum superficialis and flexor carpi radialis. Flexor carpi ulnaris is the most medial of the superficial flexors.
Innervation of the flexor carpi ulnaris muscle is from the brachial plexus via the ulnar nerve (C7-T1).
Flexor carpi ulnaris receives its arterial blood supply via three different routes. Proximally, a branch of the posterior ulnar recurrent artery supplies the muscle as it passes between the humeral and ulnar heads. Branches of the ulnar artery supply the middle and distal parts of the muscle, with an accessory supply also present distally via the inferior ulnar collateral artery.
Due to its position and direction in the forearm, flexor carpi ulnaris can move the hand sideways as well as flexing it. Contracting with flexor carpi radialis and palmaris longus, flexor carpi ulnaris produces flexion of the hand at the wrist joint. However, when it contracts alongside the extensor carpi ulnaris muscle in the posterior compartment, their counteracting forces produce adduction of the hand at the wrist, otherwise known as ulnar deviation or ulnar flexion
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
SESSION STATS - PERFORMANCE PER SPECIALTY
