-
Question 1
Correct
-
Amongst the following cells, which is responsible for the secretion of defensins?
Your Answer: Neutrophils
Explanation:Eosinophils are phagocytic and they are directed against helminths. Basophils are involved in allergic reactions and contain histamine and vasoactive granules in their cytoplasm. Mast cells are similar to basophils. Monocytes differentiate into macrophages in the tissue, secret interleukins and are phagocytic. Neutrophils are phagocytic but are also responsible for secreting defensins.
-
This question is part of the following fields:
- Immunology
- Medicine
-
-
Question 2
Correct
-
Which one of the following nerve fibers is involved in proprioception?
Your Answer: An α fiber
Explanation:Proprioception, also known as kinaesthesia, is the sense through which humans perceive their own position and movements. α nerve fibers are specifically involved in transmitting proprioception stimuli.
-
This question is part of the following fields:
- Medicine
- Neurology
-
-
Question 3
Incorrect
-
Mean intra pleural pressure at rest with inspiration can reach:
Your Answer: -2.5 mmHg
Correct Answer: -6 mmHg
Explanation:It is a negative pressure as it is lower than the atmospheric pressure. It can start from -2.5 and reach around -6 mmHg
-
This question is part of the following fields:
- Medicine
- Respiratory
-
-
Question 4
Incorrect
-
The collection of genes that are termed the major histocompatibility complex (MHC) are found on:
Your Answer: On the human leukocyte antigens
Correct Answer: Short arm of chromosome 6
Explanation:Histocompatibility, or tissue compatibility, is the property of having the same, or sufficiently similar, alleles of a set of genes called human leukocyte antigens (HLA). HLA is the human form of the major histocompatibility complex (MHC) genes found in all vertebrates. On a population level there is a great number of different alleles at each HLA locus on the short arm of chromosome 6
-
This question is part of the following fields:
- Immunology
- Medicine
-
-
Question 5
Incorrect
-
Which of the following is not innervated by the parasympathetic nerve supply?
Your Answer:
Correct Answer: Radial muscle of iris
Explanation:The sphincter pupillae is supplied by the parasympathetic fibers from the Edinger Westphal nucleus of the oculomotor nerve. The dilator pupillae (radial muscle) is supplied by the postganglionic fibers of the superior cervical sympathetic ganglion. The parasympathetic nerve supply to the salivary glands originate in the parasympathetic nucleus of the facial nerve (superior salivatory nucleus) and the glossopharyngeal nerve (inferior salivatory nucleus). The parasympathetic preganglionic fibers originate in the dorsal nucleus of the vagus nerve and descend into the thorax in the vagus nerve. The fibers terminate by synapsing with postganglionic neurons in the cardiac plexuses. Postganglionic fibers terminate on the sinoatrial and atrioventricular nodes and on the coronary arteries Parasympathetic supply to the stomach is via the vagus nerve.
-
This question is part of the following fields:
- Medicine
- Neurology
-
-
Question 6
Incorrect
-
An 81-year-old male presented to the emergency department following a fall at home. He was diagnosed with osteoporosis about five years ago. He presently complains of significant low back pain. A lumbar spine X-ray was suggestive of a fractured lumbar vertebra. A subsequent MRI scan of the lumbosacral spine revealed a new L3 burst fracture with no evidence of cord compression. A neurosurgical consult was sought and conservative management was planned accordingly in the form of pain control, physiotherapy, and mobilization (as allowed by the pain). He also has been diagnosed with chronic renal disease (stage IV) with a creatinine clearance of 21ml/min, he was started on a Buprenorphine patch. Which of the following opioids would be safest to use for his breakthrough pain?
Your Answer:
Correct Answer: Oxycodone
Explanation:Oxycodone is a safer opioid to use in patients with moderate to end-stage renal failure.Active metabolites of morphine accumulate in renal failure which means that long-term use is contraindicated in patients with moderate/severe renal failure. These toxic metabolites can accumulate causing toxicity and risk overdose. Oxycodone is mainly metabolised in the liver and thus safer to use in patients with moderate to end-stage renal failure with dose reductions.Adverse effects:Constipation is the most common overall side effect. Others include: asthenia, dizziness, dry mouth, headache, nausea, pruritus, etc. Medications in renal failure:Drugs to be avoided in patients with renal failureAntibiotics: tetracycline, nitrofurantoinNSAIDsLithiumMetforminDrugs that require dose adjustment:Most antibiotics including penicillin, cephalosporins, vancomycin, gentamicin, streptomycinDigoxin, atenololMethotrexateSulphonylureasFurosemideOpioidsRelatively safe drugs:Antibiotics: erythromycin, rifampicinDiazepamWarfarin
-
This question is part of the following fields:
- Medicine
- Pharmacology
-
-
Question 7
Incorrect
-
The celiac trunk consists of which arteries?
Your Answer:
Correct Answer: Left gastric, common hepatic, splenic
Explanation:The celiac trunk is the first major branch of the abdominal aorta. It is 1.25 cm in length. Branching from the aorta at thoracic vertebra 12 (T12). There are three main divisions of the celiac artery:- left gastric artery- common hepatic artery- splenic artery
-
This question is part of the following fields:
- Cardiovascular
- Medicine
-
-
Question 8
Incorrect
-
Which of the following is the most common causative organism in infective endocarditis?
Your Answer:
Correct Answer: Streptococcus viridans
Explanation:Viridans Alpha-haemolytic streptococci, that are present in the mouth are the most frequently isolated microorganisms when the infection is acquired in a community setting. In contrast, Staphylococcus blood stream infections are frequently acquired in a health care setting where they can enter the blood stream through procedures that cause break in the integrity of skin like surgery, catheterisation or during access of long term indwelling catheters or secondary to intravenous injection of recreational drugs.Prosthetic valve endocarditis is commonly caused by Staphylococcus epidermidis as it is capable of growing as a biofilm on plastic surfaces
-
This question is part of the following fields:
- Cardiovascular
- Medicine
-
-
Question 9
Incorrect
-
Blood flow to the subendocardial portions of the left ventricular muscle occurs mainly during:
Your Answer:
Correct Answer: Diastole
Explanation:The sub endocardium receives the least amount of blood from the coronary arteries. During systole the coronary arteries collapse as a result of the pressure from contraction that is exerted on them. During diastole the heart muscle relaxes and the pressure on the coronary vessels is relieved allowing blood to flow through them to the sub endocardium.
-
This question is part of the following fields:
- Cardiovascular
- Medicine
-
-
Question 10
Incorrect
-
A 50-year-old man with a history of hyperlipidaemia, currently under treatment with simvastatin 10mg was found to have persistently high cholesterol levels. Previous attempts to increase the dose of simvastatin have resulted in myalgia. Given this history, which one of the following lipid-regulating drugs should definitely be avoided?
Your Answer:
Correct Answer: Bezafibrate
Explanation:Both fibrates and nicotinic acid have been associated with myositis, especially when combined with a statin. However, the Committee on Safety of Medicines has produced guidance which specifically warns about the concomitant prescription of fibrates with statins concerning muscle toxicity.Bezafibrate: It is a fibric acid derivative (fibrate) that has been used as a class of agents known to decrease triglyceride levels while substantially increasing HDL-C levels.Pharmacological effects:- Increases VLDL catabolism by increasing lipoprotein and hepatic triglyceride lipase.- Decreases triglyceride synthesis by inhibiting acetyl-CoA reductase.- Decreases cholesterol synthesis by inhibiting HMG-CoA reductase.Side effects:- Hypersensitivity- Primary biliary cirrhosis- Pre-existing gallbladder disease- Concurrent use with HMG-CoA inhibitors (statins) can produce myopathy- Hepatic/renal impairment in a patient warrants dose adjustment as this drug is primarily excreted via the renal mechanism.Contraindications: Concurrent use of MAO inhibitors, hypersensitivity, pre-existing cholestasis, and pregnancy.Use: It can be used to treat Barth syndrome (characterized by dilated cardiomyopathy, neutropenia (presenting with recurrent infections), skeletal myopathy and short stature)
-
This question is part of the following fields:
- Medicine
- Pharmacology
-
-
Question 11
Incorrect
-
The predominant site in the lymph node where B lymphocytes are found is:
Your Answer:
Correct Answer: Cortex
Explanation:The cortex of the lymph node consists of the lymphoid nodules and sinusoids and posses a germinal centre from which B cells proliferate. The cortex of the lymph node predominately consists of B cells.
-
This question is part of the following fields:
- Immunology
- Medicine
-
-
Question 12
Incorrect
-
A 60-year-old male is under treatment with azathioprine after a renal transplant. During his review, he complains of pain and swelling over his left great toe. Investigations reveal hyperuricemia. Suspecting gout, he was started on allopurinol. Subsequently, he develops aplastic anaemia. Which of the following is the most appropriate reason for his bone marrow failure?
Your Answer:
Correct Answer: Mercaptopurine toxicity
Explanation:The cause for bone marrow suppression in this patient is most probably mercaptopurine toxicity.Azathioprine is metabolized to 6-mercaptopurine (6-MP), which itself is metabolized by xanthine oxidase. Xanthine oxidase inhibition by allopurinol leads to the accumulation of 6-MP which then precipitates bone marrow failure. This may be potentially fatal if unrecognized.Clinical presentation:Toxicity symptoms include gastrointestinal symptoms, bradycardia, hepatotoxicity, myelosuppression.
-
This question is part of the following fields:
- Medicine
- Pharmacology
-
-
Question 13
Incorrect
-
Among the following which is the beneficial effect of nitro-glycerine?
Your Answer:
Correct Answer: Dilation of systemic veins
Explanation:Dilation of systemic veins is a beneficial effect of nitro-glycerine.Administration of nitro-glycerine results in the dilation of systemic veins and decrease of myocardial wall tension and oxygen demand. Dilatation of systemic veins can cause reduced systemic vascular resistance leading to reduced cardiac workload thus reducing anginal symptoms secondary to demand ischemia.This is accompanied by vasodilation of large and medium-sized coronary arteries with increased coronary blood flow to the sub endocardium.
-
This question is part of the following fields:
- Medicine
- Pharmacology
-
-
Question 14
Incorrect
-
Consanguinity shows a strong association with which pattern of inheritance?
Your Answer:
Correct Answer: Autosomal recessive
Explanation:Consanguinity involves being from the same kinship as another person. It is a common feature of an autosomal recessive mode of inheritance
-
This question is part of the following fields:
- Genetics
- Medicine
-
-
Question 15
Incorrect
-
Cyclic AMP activates the following enzyme
Your Answer:
Correct Answer: Protein Kinase A
Explanation:Cyclic AMP works by activating protein kinase A (PKA, or cAMP-dependent protein kinase). Protein kinase A can also phosphorylate specific proteins that bind to promoter regions of DNA, causing increases in transcription.
-
This question is part of the following fields:
- Cell Biology
- Medicine
-
-
Question 16
Incorrect
-
The conversion of haem to bilirubin is catalysed by which of these enzymes?
Your Answer:
Correct Answer: Biliverdin reductase
Explanation:Bilirubin is created by the activity of biliverdin reductase on biliverdin, a green tetrapyrrolic bile pigment that is also a product of haem catabolism.
-
This question is part of the following fields:
- Hepatobiliary
- Medicine
-
-
Question 17
Incorrect
-
During which phase of the cardiac cycle does most of the ventricular filling occur?
Your Answer:
Correct Answer: Ventricular diastole
Explanation:During the phase of ventricular diastole when the heart muscle relaxes and all the valves are open, blood flows easily into the heart. This is the phase of rapid ventricular filling. During isovolumetric contraction and relaxation the volume of blood in the heart does not change. During ventricular ejection blood enters into the aorta and pulmonary vessels.
-
This question is part of the following fields:
- Cardiovascular
- Medicine
-
-
Question 18
Incorrect
-
A 22-year-old university student is admitted after taking drugs at a night club. Which of the following features suggest she had taken ecstasy (MDMA)?
Your Answer:
Correct Answer: A pyrexia of 40°C
Explanation:MDMA commonly known as ecstasy or molly, is a psychoactive drug primarily used as a recreational drug. The desired effects include altered sensations, increased energy, empathy, and pleasure. Features of MDMA abuse include hyponatraemia, tachycardia, hyperventilation, and hyperthermia.
-
This question is part of the following fields:
- Medicine
- Pharmacology
-
-
Question 19
Incorrect
-
Which of the following cells are attracted to the surface of endothelium by selectins?
Your Answer:
Correct Answer: Neutrophils
Explanation:Selectins are expressed on the surface of the endothelium. P selectins are released from weibel-palade bodies and E selectins are induced by cytokines (TNF and IL-1). They bind to receptors on the neutrophils called saiyl lewis X.
-
This question is part of the following fields:
- Immunology
- Medicine
-
-
Question 20
Incorrect
-
A 56 year old obese female presents due to moderate pain in her finger joints which occurs mostly at the end of the day which gets better with rest. There is also some associated swelling. On examination, there is enlargement of her distal interphalangeal joints and tenderness to palpation. Which of the following is the most likely diagnosis?
Your Answer:
Correct Answer: Osteoarthritis
Explanation:Osteoarthritis (OA) is a disabling joint disease characterized by a noninflammatory degeneration of the joint complex (articular cartilage, subchondral bone, and synovium) that occurs with old age or from overuse. It mainly affects the weight-bearing and high-use joints, such as the hip, knee, hands, and vertebrae. Despite the widespread view that OA is a condition caused exclusively by degenerative “wear and tear” of the joints, newer research indicates a significant heterogeneity of causation, including pre-existing peculiarities of joint anatomy, genetics, local inflammation, mechanical forces, and biochemical processes that are affected by proinflammatory mediators and proteases. Major risk factors include advanced age, obesity, previous injuries, and asymmetrically stressed joints. In early-stage osteoarthritis, patients may complain of reduced range of motion, joint-stiffness, and pain that is aggravated with heavy use. As the disease advances, nagging pain may also occur during the night or at rest. Diagnosis is predominantly based on clinical and radiological findings. Classic radiographic features of OA do not necessarily correlate with clinical symptoms and appearance. RA involves proximal interphalangeal joints not distal. Gout occurs as a result of overproduction or underexcretion of uric acid and frequently involves first toe. Fibromyalgia is a disorder characterized by widespread musculoskeletal pain accompanied by fatigue, sleep, memory and mood issues.
-
This question is part of the following fields:
- Connective Tissue
- Medicine
-
-
Question 21
Incorrect
-
In the cardiac cycle, all of the following are true except:
Your Answer:
Correct Answer: Mitral valve is closed by contraction of papillary muscles
Explanation:Mitral valve is closed by contraction of papillary muscles: This statement is incorrect. The mitral valve closes due to the pressure difference between the left ventricle and the left atrium at the onset of ventricular systole. The papillary muscles contract to prevent prolapse of the valve into the atrium but do not cause the valve to close.
The left ventricular volume is maximal at the end of atrial systole: This statement is true. At the end of atrial systole, the atria have pushed the remaining blood into the ventricles, making the ventricular volume maximal (end-diastolic volume).
The left ventricular pressure is maximal just before the aortic valve opens: This statement is true. Left ventricular pressure peaks just before the aortic valve opens, as the ventricle contracts to overcome the pressure in the aorta.
The ejection fraction is about 55%: This statement is true. The ejection fraction, which is the percentage of blood ejected from the ventricles with each contraction, is typically around 55%.
The ‘a’ wave is due to atrial systole: This statement is true. The ‘a’ wave on the venous pressure curve corresponds to atrial systole, reflecting the increased pressure from atrial contraction.
-
This question is part of the following fields:
- Cardiovascular
- Medicine
-
-
Question 22
Incorrect
-
Select one true statement about haemoglobin synthesis…
Your Answer:
Correct Answer: Occurs in the cytosol of developing red cells.
Explanation:Haemoglobin (Hb) is synthesized in a complex series of steps. The haem part is synthesized in a series of steps in the mitochondria and the cytosol of immature red blood cells, while the globin protein parts are synthesized by ribosomes in the cytosol. Production of Hb continues in the cell throughout its early development from the proerythroblast to the reticulocyte in the bone marrow.
-
This question is part of the following fields:
- Haematology
- Medicine
-
-
Question 23
Incorrect
-
A 35-year-old woman under treatment for long-term epilepsy with valproate presented with complaints of excessive weight gain. She is consuming oral contraceptive pills.Which among the following is the best alternative to valproate for treating long-term epilepsy?
Your Answer:
Correct Answer: Lamotrigine
Explanation:Among the given anti-epileptics the best drug that can be given in this patient is lamotrigine.Topiramate, carbamazepine, phenytoin, and phenobarbital are all hepatic enzyme inducers and are associated with decreased effectiveness of the oral contraceptive (OCP) due to acceleration of the metabolism of oestrogens and progestogens.If she is planning on pregnancy then registry studies suggest that lamotrigine would also be the best choice.Other hepatic enzyme inducers include rifampicin, spironolactone, griseofulvin, etc.
-
This question is part of the following fields:
- Medicine
- Pharmacology
-
-
Question 24
Incorrect
-
The coronary sinus drains into the:
Your Answer:
Correct Answer: Right atrium
Explanation:The coronary sinus drains into the right atrium. Most of the venous blood returns to the heart via the coronary sinus and the anterior cardiac veins. Apart from these there are other vessels that drain directly into the heart chambers.
-
This question is part of the following fields:
- Cardiovascular
- Medicine
-
-
Question 25
Incorrect
-
A 32 year old male who has recently returned from a trip to Thailand presents with congestion of eyes and swelling of the knee joint. He completed a course of antibiotics for dysentery 4 weeks back. He experiences no dysuria and urine examination is normal. Which further information would be most useful in establishing a diagnosis?
Your Answer:
Correct Answer: History and physical examination
Explanation:The patient most likely has reactive arthritis which is usually diagnosed on history and clinical examination. The classic triad of symptoms include conjunctivitis, urethritis and arthritis. Arthritis and conjunctivitis may occur 4-6 weeks after a gastrointestinal or genitourinary infection. Arthritis usually occurs acutely, mostly involving the lower limb and is asymmetrical. Blood culture, urine culture and arthrocentesis (joint aspiration) will not yield positive results.
-
This question is part of the following fields:
- Connective Tissue
- Medicine
-
-
Question 26
Incorrect
-
A 64 year old woman who is of Asian descent and is diabetic (controlled by diet) presents with generalized body aches and difficulty rising from sitting for the last few months. Her blood glucose levels are in the normal range. Lab examination reveals normal blood cell count, low serum phosphate, calcium at the lower range, and raised alkaline phosphatase levels. Radiological examination shows which of the following?
Your Answer:
Correct Answer: Linear areas of low density
Explanation:Osteomalacia is a condition due to defective mineralization of osteoid. Occurs as a result of Vitamin D deficiency secondary to poor dietary intake and sun exposure, malabsorption e.g., inflammatory bowel disease and gastrointestinal bypass surgery. Radiological findings include reduced bone mineral density (a non specific finding), inability to radiologically distinguish vertebral body trabeculae (the film appears poor quality), looser pseudo fractures, fissures, or narrow radiolucent lines (these are the characteristic findings). Osteolytic or punched out lesions may be seen with multiple myeloma and bony metastases. Areas of sclerosis may be observed with conditions like osteosclerosis and Paget disease. A Brodie abscess is a subacute osteomyelitis, which may persist for years before progressing to a chronic, frank osteomyelitis.
-
This question is part of the following fields:
- Connective Tissue
- Medicine
-
-
Question 27
Incorrect
-
Which vitamin plays a major role in the metabolism of many amino acids?
Your Answer:
Correct Answer: Vitamin B6
Explanation:Vitamin B6 is part of the vitamin B group, and its active form, pyridoxal 5′-phosphate (PLP) serves as a coenzyme in many enzyme reactions in amino acid, glucose, and lipid metabolism.
-
This question is part of the following fields:
- Haematology
- Medicine
-
-
Question 28
Incorrect
-
The immunoglobulin found in the highest concentration in humans is
Your Answer:
Correct Answer: IgG
Explanation:Representing approximately 75% of serum antibodies in humans, IgG is the most common type of antibody found in the circulation. IgG molecules are created and released by plasma B cells.
-
This question is part of the following fields:
- Immunology
- Medicine
-
-
Question 29
Incorrect
-
Adrenergic stimulation will lead to myocyte relaxation via the following mechanisms
Your Answer:
Correct Answer: Increased phosphorylation of phosholamban
Explanation:Phosphorylation of phospholamban, which increases calcium ATPase activity and sequestration of calcium in the sarcoplasmic reticulum. An increased rate of relaxation is explained because cAMP also activates the protein phospholamban, situated on the membrane of the SR, that controls the rate of uptake of calcium into the SR. The latter effect explains enhanced relaxation (lusitropic effect).
-
This question is part of the following fields:
- Cardiovascular
- Medicine
-
-
Question 30
Incorrect
-
Where does the pituitary gland lie?
Your Answer:
Correct Answer: In a pocket of the sphenoid bone at the base of the brain
Explanation:The pituitary lies in a small depression in the sphenoid bone, known as the sella turcica or Turkish saddle.
-
This question is part of the following fields:
- Endocrinology
- Medicine
-
SESSION STATS - PERFORMANCE PER SPECIALTY
