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Question 1
Correct
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The triangle with the heart at its centre, using limb leads is called:
Your Answer: Einthoven
Explanation:The Einthoven triangle is formed by placing the limb leads on both the arms and on the left leg with the heart in the centre.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 2
Correct
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A 18-year-old female is brought to the emergency department by her boyfriend. He is concerned that she may have taken an overdose of her mom's morphine sulphate pills after being depressed about her mother, who is dying of carcinoma of the breast.Which of the following may point towards his suspicion?
Your Answer: Sweating
Explanation:Excessive sweating points towards a morphine overdose.Morphine is considered the classic opioid analgesic with which other painkillers are compared. Like other medications in this class, morphine has an affinity for delta, kappa, and mu-opioid receptors.Most commonly used in pain management, morphine provides major relief to patients afflicted with pain.Among the more common adverse effects of morphine use is constipation. Other side effects include nausea, vomiting, drowsiness, and confusion. Psychological and physical dependence may occur.Other side effects include bronchospasm, angioedema, urinary retention, ureteric or biliary spasm, dry mouth, sweating, rash, facial flushing, vertigo, tachycardia, bradycardia, palpitations, orthostatic hypotension, hypothermia, restlessness, mood change, hallucinations, seizures (adults and children) and miosis, headache and allergic reactions (including anaphylaxis) and decreased libido or potency.Raised intracranial pressure occurs in some patients. Muscle rigidity may occur with high doses. Elevated liver enzymes may occur due to biliary sphincter constriction. Large doses can lead to respiratory depression, circulatory failure, and coma.Treatment of opioid overdose:Initial treatment of overdose begins with supportive care.Naloxone is a pure competitive antagonist of opiate receptors and has no agonistic activity. The drug is relatively safe and can be administered intravenous, intramuscular, subcutaneous or via the endotracheal tube.Alternatively, nalmefene and naltrexone maybe considered.
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This question is part of the following fields:
- Medicine
- Pharmacology
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Question 3
Incorrect
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A lesion that interrupts one optic nerve causes blindness:
Your Answer: Bilateral, same site of visual fields, in half of the visual fields (homonymous hemianopia)
Correct Answer: In the eye on the same side as the optic nerve
Explanation:The optic nerve on each side contains medial and lateral fibers originating from the retina. Medial fibers cross at the optic chiasm and become the optic tract ending in the visual cortex of the occipital lobe. If there is a lesion interrupting the “optic nerve” on one side, the same side eye will be completely blind.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 4
Correct
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Dietary starch is mainly:
Your Answer: Amylopectin
Explanation:Dietary starch consists of two types of molecules: the linear and helical amylose and the branched amylopectin. Starch generally contains 20 to 25% amylose and 75 to 80% amylopectin by weight but depends in the plant. Glycogen, the glucose store of animals, is a more branched version of amylopectin.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 5
Incorrect
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The rate of depolarisation of the sinus node membrane potential is modulated by all the following except:
Your Answer: Autonomic tone
Correct Answer: Cardiac output
Explanation:Cardiac output has no effect on the depolarization of the pacemaker potential of the heart.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 6
Correct
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Which of the following best describes the cardiac muscle?
Your Answer: Striated and involuntary
Explanation:Cardiac muscle (heart muscle) is an involuntary, striated muscle that is found in the walls and histological foundation of the heart, specifically the myocardium. Cardiac muscle is one of three major types of muscle, the others being skeletal and smooth muscle.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 7
Correct
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With regard to cell membrane proteins:
Your Answer: Carriers are involved in facilitated diffusion
Explanation:Pumps use a source of free energy such as ATP to transport ions against a gradient and is an example of active transport. Unlike channel proteins which only transport substances through membranes passively, carrier proteins can transport ions and molecules either passively through facilitated diffusion, or via secondary active transport. Channels are either in open state or closed state. When a channel is opened, it is open to both extracellular and intracellular. Pores are continuously open to both environments, because they do not undergo conformational changes. They are always open and active.
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This question is part of the following fields:
- Cell Biology
- Medicine
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Question 8
Correct
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When is the blood pressure at its lowest during pregnancy?
Your Answer: Second trimester
Explanation:It is lowest during the second trimester.
Previous studies have reported changes in blood pressure (BP) throughout pregnancy, and it was generally accepted that in clinically healthy pregnant women, BP falls gradually at first trimester, reaching the lowest around 22–24 weeks, rising again from 28 weeks, and reaching preconception levels by 36 weeks of gestation
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 9
Correct
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The following is true in relation to coronary venous drainage?
Your Answer: Most venous return ultimately drains into right atrium via the coronary sinus
Explanation: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
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 10
Correct
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Question 11
Correct
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The axons of which neurons serve as the only output from the cerebellar cortex?
Your Answer: Purkinje
Explanation:The cerebellar cortex consist of 3 layers. The molecular layer, the granule cell layer and the Purkinje cell layer in the middle. The Purkinje cells project into the deep cerebellar nuclei. They are the only output cells of the cerebellar cortex.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 12
Correct
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The T-tubular system in cardiac muscle is:
Your Answer: Transmits action potential from sarcolemma to the SR to allow for Ca2+ release into the cytoplasm
Explanation:Action potentials are transmitted to the fibrils of a fiber through the T tubule system. It triggers the release of Ca 2+ from the terminal cisterns. Depolarization of the T tubules activates the sarcoplasmic reticulum through the dihydropyridine receptors, which are voltage gated calcium channels.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 13
Correct
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Where is the normal upper border of the liver situated?
Your Answer: 6th rib midclavicular line on right
Explanation:Assessment of liver margins is important clinically to determine the size of the liver and is done via percussion during the physical examination. The liver typically extends from the fifth intercostal space or 6th rib to the right costal margin in the midclavicular line and the 10th rib on anterior axillary line.
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This question is part of the following fields:
- Hepatobiliary
- Medicine
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Question 14
Incorrect
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A 56-year-old male presents to the emergency department with confusion and agitation for the past four hours. He is a known alcoholic who has abstained from drinking for the past three days.On examination, he is sweating, agitated and disorientated. His temperature is 37.7°C, pulse 112 bpm regular and blood pressure is 150/76 mmHg. Blood investigations performed in the emergency department reveal:FBC: NormalU&E: NormalPlasma glucose: 4.6 mmol/l (3.6-6)Which of the following medications would be the most appropriate treatment for this man?
Your Answer: Oral diazepam
Correct Answer: Oral lorazepam
Explanation:The most probable diagnosis for this patient is delirium tremens due to alcohol withdrawal, which should be treated as a medical emergency. Delirium tremens is a hyperadrenergic state and is often associated with tachycardia, hyperthermia, hypertension, tachypnoea, tremor, and mydriasis.Treatment:- The most common and validated treatment for alcohol withdrawal is benzodiazepine: first-line treatment includes oral lorazepam. – If the symptoms persist, or the medication is refused, parenteral lorazepam, haloperidol or olanzapine should be given.- Central-acting, alpha-2 agonists such as clonidine and dexmedetomidine should not be used alone for the treatment of alcohol withdrawal.- It is also recommended to avoid using alcohol, antipsychotics, anticonvulsants, beta-adrenergic receptor blockers, and baclofen for the treatment of alcohol withdrawal as there are not enough studies to support the safety of these.
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This question is part of the following fields:
- Medicine
- Pharmacology
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Question 15
Correct
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The following can cause steatorrhea except
Your Answer: Diseases that destroy the endocrine portion of the pancreas
Explanation:Dietary fats and lipids are usually efficiently digested and over 90% absorbed. Impaired digestion or absorption can result in fatty stools. Possible causes include exocrine (not endocrine) pancreatic insufficiency, with poor digestion from lack of lipases, loss of bile salts, which reduces micelle formation, and small intestinal disease producing malabsorption. Various other causes including certain medicines that block fat absorption, or indigestible or excess oil/fat in diet.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 16
Correct
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A 24-year-old women presents following an overdose. Which one of the following would suggest anticholinergic syndrome?
Your Answer: Mydriasis occurs
Explanation:Anticholinergic syndrome results from the inhibition of muscarinic cholinergic neurotransmission. Clinical manifestations can be remembered by the mnemonic, red as a beet, dry as a bone, blind as a bat, mad as a hatter, hot as a hare, and full as a flask. The mnemonic refers to the symptoms of flushing, dry skin and mucous membranes, mydriasis (dilated pupil) with loss of accommodation, altered mental status, fever, and urinary retention, respectively.
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This question is part of the following fields:
- Medicine
- Pharmacology
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Question 17
Correct
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Why is tissue plasminogen activator (tPa) a valuable treatment used in myocardial infarction and stroke?
Your Answer: It forms plasmin from its inactive precursor
Explanation:tPA is a serine protease involved in the breakdown of blood clots. It functions by converting plasminogen, an inactive precursor, into plasmin, an active enzyme. Plasmin then degrades fibrin, the main protein component of blood clots, leading to clot dissolution. This mechanism is particularly valuable in the treatment of myocardial infarction (heart attack) and ischemic stroke, where timely dissolution of the clot can restore blood flow to affected tissues and reduce damage.
Therefore, the correct answer is:
- It forms plasmin from its inactive precursor
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This question is part of the following fields:
- Haematology
- Medicine
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Question 18
Correct
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In a study, 50 out of 100 smokers developed lung cancers and 50 out of 200 non-smokers developed lung cancers. Which of the following is accurate?
Your Answer: Relative risk=2
Explanation:Relative risk = (Incidence in exposed group)/incidence in unexposed group). So in this case RR = (50/100)/(50/200) = 2.
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This question is part of the following fields:
- Medicine
- Research Skills
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Question 19
Correct
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The main efferent input of the posterior pituitary gland comes from:
Your Answer: Paracrine hormones secreted from the hypothalamus via axons.
Explanation:The posterior pituitary or neurohypophysis consists of a collection of axonal projections emerging from the hypothalamus. It releases hormones directly from these axonal endings into circulation; these hormones are oxytocin and vasopressin.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 20
Correct
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What is the blood supply to the liver?
Your Answer: Hepatic artery and hepatic portal vein
Explanation:The liver receives a dual blood supply from the hepatic portal vein and hepatic arteries. The hepatic portal vein delivers approximately 75% of the liver’s blood supply, and carries venous blood drained from the spleen, gastrointestinal tract, and its associated organs. The hepatic arteries supply arterial blood to the liver, accounting for the remaining quarter of its blood flow. Oxygen is provided from both sources; approximately half of the liver’s oxygen demand is met by the hepatic portal vein, and half is met by the hepatic arteries
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This question is part of the following fields:
- Hepatobiliary
- Medicine
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Question 21
Correct
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Coronary arteries fill up during
Your Answer: Diastole
Explanation:During contraction of the ventricular myocardium (systole), the subendocardial coronary vessels (the vessels that enter the myocardium) are compressed due to the high ventricular pressures. This compression results in momentary retrograde blood flow (i.e., blood flows backward toward the aorta) which further inhibits perfusion of myocardium during systole. However, the epicardial coronary vessels (the vessels that run along the outer surface of the heart) remain open. Because of this, blood flow in the sub endocardium stops during ventricular contraction. As a result, most myocardial perfusion occurs during heart relaxation (diastole) when the subendocardial coronary vessels are open and under lower pressure.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 22
Correct
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Troponin I is inhibited by calcium binding to:
Your Answer: Troponin c
Explanation:At rest troponin I is bound to actin and tropomyosin and covers the site where the myosin head interacts with actin. When calcium enters into the muscle, it binds with troponin C and cause a structural change in troponin I which moves out of the myosin binding site and causes the cross bridges between the actin and myosin filaments to occur.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 23
Correct
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Mutation in RB can lead to the formation of which cancer?
Your Answer: Retinoblastoma
Explanation:Patients with a history of autosomal dominant familial retinoblastoma have at least one mutated copy of the RB gene. This predisposes the patient to develop retinoblastoma in one or both the eyes. Patients with a family history should be screened properly so that it can be detected and treated as early as possible.
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This question is part of the following fields:
- Genetics
- Medicine
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Question 24
Correct
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A 72-year-old with varicose veins complains of swollen, red, itchy legs. Which is the most likely diagnosis?
Your Answer: Varicose eczema
Explanation:Varicose eczema is a common problem, particularly in elderly patients due to stasis or blood pooling from insufficient venous return; the alternative name of varicose eczema comes from a common cause of this being varicose veins. It is often mistaken for cellulitis, but cellulitis is rarely bilateral and is painful rather than itchy.
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This question is part of the following fields:
- Dermatology
- Medicine
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Question 25
Incorrect
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Almost all of the protein that appears in the stool is:
Your Answer: Liver proteins
Correct Answer: Comes from bacteria and cellular debris
Explanation:75% of faecal weight is water. By dry weight 30% of faeces is bacteria,10-20% is fat and 2-3% proteins. Almost all proteins ingested are absorbed in the gut.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 26
Correct
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According to Starling's law of the heart:
Your Answer: The extent of the preload is proportional to the end-diastolic volume
Explanation:Frank starlings law describes that an increase in the venous return or the end diastolic volume will cause an increase in the stroke volume/ preload and also cardiac output. It stems from the fact that increased venous return will increase the stretch on the ventricular muscle fibers. The sarcomere will stretch a considerable length that is needed for maximum contraction and the development of tension in the muscle fiber. The greater the venous return the greater the cardiac output. This relationship is directly proportional.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 27
Incorrect
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Which of the given adverse effects should be anticipated following the administration of an anticholinesterase?
Your Answer: Bradycardia and urinary retention
Correct Answer: Bradycardia and miosis
Explanation:Bradycardia and miosis should be anticipated following the administration of anticholinesterases.Anticholinesterase agents include the following medications:- Pyridostigmine, neostigmine, and edrophonium which play a significant role in the diagnosis and the management of myasthenia gravis.- Rivastigmine, galantamine and donepezil are cholinesterase inhibitors found to be significantly useful in the management of Alzheimer’s disease.Mechanism of action and pharmacological effects:Inhibition of cholinesterase increases the level and the duration of action of acetylcholine within the synaptic cleft. Thus, cholinergic effects such as a reduction in heart rate (bradycardia), miosis (pupillary constriction), increased secretions, increased gastrointestinal motility and reduction in BP may occur with anticholinesterases.Toxins such as organophosphates and carbamates also are primarily anticholinergic and cause the following typical SLUDGE symptoms:- Salivation- Lacrimation- Urination- Diaphoresis- Gastrointestinal upset- Emesis
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This question is part of the following fields:
- Medicine
- Pharmacology
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Question 28
Incorrect
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A 28 year old male arrives at the clinic complaining of fever, arthralgia and urethritis. On examination, the ankle is swollen and there is a pustular rash on the dorsal foot. What is the most likely diagnosis?
Your Answer: Reactive arthritis
Correct Answer: Disseminated gonorrhoea
Explanation:DGI presents as two syndromes: 1) a bacteremic form that includes a triad of tenosynovitis, dermatitis, and polyarthralgias without purulent arthritis and 2) a septic arthritis form characterized as a purulent arthritis without associated skin lesions. Many patients will have overlapping features of both syndromes. Time from infection to clinical manifestations may range from 1 day to 3 months. There is no travel history and the rash of Lyme disease is not purulent. Reactive arthritis presents with conjunctivitis, urethritis and arthritis usually with a red hot tender and swollen joint.
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This question is part of the following fields:
- Connective Tissue
- Medicine
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Question 29
Correct
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90% of erythropoietin necessary for haemopoesis is produced by the kidneys, the remainder is formed in the?
Your Answer: Liver
Explanation:Erythropoietin is produced by interstitial fibroblasts in the kidney in close association with peritubular capillary and proximal convoluted tubule. It is also produced in perisinusoidal cells in the liver. While liver production predominates in the fetal and perinatal period, renal production is predominant during adulthood.
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This question is part of the following fields:
- Haematology
- Medicine
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Question 30
Correct
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Regarding the length of systole and diastole which of the following is true?
Your Answer: The duration of systole is more fixed than diastole
Explanation:The duration of systole is more fixed than the duration of diastole. When the heart rate increases the timing of systole remains more or less the same however, diastole decreases.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 31
Correct
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What happens first during depolarisation of the membrane potential?
Your Answer: Gated Na channels open allowing the influx of Na
Explanation:Generation of an action potential in response to a stimulus is a result of a previously maintained resting membrane potential (RMP). Generation of resting membrane potential is mediated mainly by potassium ions. Several membrane proteins maintain RMP by transport of ions in and out of cell. Na+/K+ ATPase pump maintains a concentration gradient of Na+ and K+ ions. Na+ concentration in extracellular fluid is higher compared to intracellular fluid and K+ ion concentration is higher intracellularly. Generation of an action potential facilitates opening of Na+ ion channels which allow for Na+ to diffuse inside the cell according to the concentration gradient.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 32
Correct
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Question 33
Correct
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Where does the pituitary gland lie?
Your 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.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 34
Incorrect
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A 78 year old woman presents to the clinic complaining of left sided temporal headaches and jaw claudication that has been going on for a month. A left temporal artery biopsy is negative. Results show:Hb: 130g/lPlatelets: 359*109/lWBC: 10*109/lCRP: 89mg/lWhich of the following options would be the next best step in the management of this patient?
Your Answer: Ultrasound of left temporal artery
Correct Answer: Commence prednisolone
Explanation:Temporal arteritis is a chronic large- and medium-sized vessel vasculitis that typically involves the temporal arteries. Classical symptoms include temporal headaches, jaw claudication, amaurosis fugax. Physical exam shows scalp tenderness, palpation of the temporal area may demonstrate an absent pulse, knot-like swelling and vision loss. Lab results reveal an increased erythematous sedimentation rate and C-reactive protein. Temporal artery biopsy confirms the diagnosis. Management approach: high-dose systemic corticosteroids should be promptly administered even before the diagnosis is established. Temporal artery biopsy confirms the diagnosis. Inability to manage this or administer glucocorticoids might lead to development of blindness.
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This question is part of the following fields:
- Connective Tissue
- Medicine
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Question 35
Incorrect
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The free radical most abundantly formed by the immune system is:
Your Answer: Superoxide
Correct Answer: Hydroxyl radical
Explanation:Neutrophil and macrophage phagocytosis stimulates various cellular processes including the respiratory burst whereby increased cellular oxygen uptake results in the production of the potent oxidant bactericidal agents, hypochlorous acid and hydroxyl radical.
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This question is part of the following fields:
- Cell Biology
- Medicine
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Question 36
Correct
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Select the correct statement about the microanatomy of the thyroid gland.
Your Answer: The capillaries adjacent to thyroid cells have a fenestrated endothelium.
Explanation:Fenestrated capillaries have a very thin endothelium, which is perforated by numerous fenestrations or pores. Hormones are usually released into these capillaries, reaching their target cells through the circulatory system.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 37
Incorrect
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Dicrotic notch is produced by which valves?
Your Answer: Pulmonary and aortic
Correct Answer: Aortic
Explanation:The graph of aortic pressure throughout the cardiac cycle displays a small dip (the incisure or dicrotic notch) which coincides with the aortic valve closure. The dip in the graph is immediately followed by a brief rise (the dicrotic wave) then gradual decline.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 38
Incorrect
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The following are examples of the functions of the vascular endothelium except:
Your Answer: Prothrombotic
Correct Answer: Tumour suppression
Explanation:Vascular endothelium has many important functions including regulation of vascular tone, molecular exchange between blood and tissue compartments, hemostasis and signaling for the immune regulation and inflammation. Depending on specific tissue needs and local stresses, endothelial cells are capable of evoking either antithrombotic or prothrombotic events. Tumor suppression is related to genes, or anti-oncogenes, that regulate a cell during cell division and replication.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 39
Correct
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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: 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
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This question is part of the following fields:
- Medicine
- Pharmacology
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Question 40
Correct
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A 55 year old cardiac patient is comfortable at rest but heavy housework results in fatigue, palpitations or dyspnoea. What New York Heart Association class best describes the severity of their disease?
Your Answer: NYHA Class II
Explanation:New York Heart Association functional classification:
Class I: no limitation is experienced in any activities; there are no symptoms from ordinary activities.
Class II: slight, mild limitation of activity; the patient is comfortable at rest or with mild exertion.
Class III: marked limitation of any activity; the patient is comfortable only at rest.
Class IV: any physical activity brings on discomfort and symptoms occur at rest.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 41
Incorrect
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Regarding the surface anatomy of the orifices of the heart, where is the aortic valve located?
Your Answer: Opposite the right upper sternal border in the 2nd intercostal space
Correct Answer: Opposite the left 3rd intercostal space to the left of the sternum
Explanation:The aortic valve is situated in the left 3rd intercostal space just beneath the sternum.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 42
Correct
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The direct determinants of cardiac output are
Your Answer: Stroke volume and heart rate
Explanation:Cardiac output is classically defined alongside stroke volume (SV) and the heart rate (HR) as:Cardiac Output [L/min] = Stroke Volume [L/beat] x Heart Rate [beats/min]
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 43
Correct
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A 46 year old male, known with Rheumatoid Arthritis presents with a swollen and painful right ankle. No drug allergies are reported. On examination, the vitals are as follows: Temp: 38.8BP: 90/60 mmHgPulse: 110/min. Right ankle examination reveals tenderness, warmth, erythema and tense joint effusion. Blood samples including blood cultures are collected and fluid resuscitation is initiated. Which of the following interventions would be most appropriate for this man?
Your Answer: Administer i.v. flucloxacillin, and arrange joint aspiration urgently
Explanation:Although microscopic analysis of joint fluid aspirate and culture is the basis of septic arthritis diagnosis and should usually be collected before the administration of antibiotics, the patient is showing signs of septic shock. A delay in antibiotics might lead to worsening of symptoms so they are administered first.
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This question is part of the following fields:
- Connective Tissue
- Medicine
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Question 44
Correct
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A 60-year-old patient diagnosed with Type-2 diabetes mellitus is not responding to dietary modifications and weight reduction. He needs to be started on an oral hypoglycaemic agent. Which among the following statements regarding oral hypoglycaemic agents is true?
Your Answer: Acarbose inhibits α-glucosidase
Explanation:Different Oral Hypoglycaemic Agents (OHAs) and their respective mechanism(s) of action include:• Sulfonylureas (such as, glipizide, gliclazide, glimepiride) – bind to ATP sensitive Potassium channels (K – ATP channels) in the 𝝱 cells of the islets of the pancreas. Inhibition of these channels lead to an altered resting membrane potential in these cells causing an influx of calcium which increases insulin secretion.• Meglitinides (like Repaglinide) through a different receptor, they similarly regulate K – ATP channels thereby causing an increase in insulin secretion.• Biguanides (e.g., Metformin) increase the hepatic AMP-activated protein kinase activity leading to reduced gluconeogenesis and lipogenesis and increased insulin-mediated uptake of glucose in muscles. (it doesn’t increase insulin secretion)• Thiazolidinediones (rosiglitazone, pioglitazone) bind to PPAR-𝝲 and increase peripheral uptake of glucose and decrease hepatic glucose production.• α-Glucosidase inhibitors (such as acarbose, miglitol, voglibose) competitively inhibit α-glucosidase enzymes in the intestine that digest the dietary starch thus, inhibiting the polysaccharide reabsorption as well as metabolism of sucrose to glucose and fructose.• DPP-4 inhibitors (sitagliptin, saxagliptin, vildagliptin, linagliptin, alogliptin) prolong the action of glucagon-like peptide. This leads to inhibition of glucagon release, increase in insulin secretion and a decrease in gastric emptying leading to a decrease in blood glucose levels.• SGLT2 inhibitors (dapagliflozin and canagliflozin) inhibit glucose reabsorption in the proximal tubules of the renal glomeruli leading to glycosuria which in-turn reduces blood glucose levels.Note: Side effects of pioglitazone are weight gain, pedal oedema, bone loss and precipitation of congestive cardiac failure.
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This question is part of the following fields:
- Medicine
- Pharmacology
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Question 45
Incorrect
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ANP and BNP in the circulation act on the kidney to?
Your Answer: Decrease sodium excretion
Correct Answer: Increase sodium excretion
Explanation:The physiologic actions of BNP are similar to those of ANP and include decrease in systemic vascular resistance and central venous pressure as well as an increase in natriuresis (sodium excretion). The net effect of these peptides is a decrease in blood pressure due to the decrease in systemic vascular resistance and, thus, afterload.
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This question is part of the following fields:
- Medicine
- Renal
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Question 46
Correct
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Glucose absorption in the small intestine is coupled with which of the following electrolytes?
Your Answer: Na
Explanation:Sodium-glucose linked transporter are family of proteins of different types. SGLT1 transporter is found in the intestinal mucosa of the small intestine and absorbs glucose via cotransport of Na+ ions.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 47
Incorrect
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On which chromosome is the gene for insulin located?
Your Answer: Chromosome 6
Correct Answer: Chromosome 11
Explanation:Humans have 23 pairs of chromosomes, and usually, two pairs of copies of chromosome 11. It is one of the most complex, gene-rich chromosomes in the human genome, and it is associated with a number of diseases. Studies have shown they the human insulin gene is located on the short arm of chromosome 11.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 48
Correct
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Which lipoprotein contains the most cholesterol esters?
Your Answer: LDL
Explanation:LDL and HDL transport both dietary and endogenous cholesterol in the plasma, but LDL is the main transporter of cholesterol and cholesteryl esters.
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This question is part of the following fields:
- Medicine
- Metabolism
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Question 49
Incorrect
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Which of the toxin secretion pathways in the cell membrane of gram– bacteria delivers the toxin extracellular in a 2 stage process to the host?
Your Answer: III
Correct Answer: II
Explanation:Gram negative bacteria contain two membranes and there are about six specialized secretion systems. The secreted proteins play a key role in pathogenesis. Type II secretion systems (T2SS) are conserved in most Gram-negative bacteria, where they transport proteins from the periplasm into the extracellular environment. Because the T2SS channel is only found in the outer membrane, proteins secreted through this apparatus must first be delivered to the periplasm via the Sec or Tat secretion pathways and then to the extracellular environment making it a two-stage process.
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This question is part of the following fields:
- Infectious Diseases
- Medicine
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Question 50
Correct
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A 22-year-old female comes to you for counselling regarding the initiation of combined oral contraceptive pill. Which of the following statements is correct?
Your Answer: She will still be protected against pregnancy if she takes amoxicillin for a lower respiratory tract infection while on the combined pill
Explanation:The true statement among the given options is that she will still be protected against pregnancy if she takes amoxicillin for a lower respiratory tract infection while on the combined pill.Other than enzyme-inducing antibiotics such as rifampicin, antibiotics do not reduce the efficacy of the combined oral contraceptive pill.It was previously advised that barrier methods of contraception should be used if taking an antibiotic while using the contraceptive pill, due to concerns that antibiotics might reduce the absorption of the pill. This is now known to be untrue. However, if the absorptive ability of the gut is compromised for another reason, such as severe diarrhoea or vomiting, or bowel disease, this may affect the efficacy of the pill.The exception to the antibiotic rule is that hepatic enzyme-inducing antibiotics such as rifampicin and rifaximin do reduce the efficacy of the pill. Other enzyme-inducing drugs, such as phenytoin, phenobarbital, carbamazepine or St John’s Wort can also reduce the effectiveness of the pill.Other options:The combined pill is often prescribed for women with heavy periods as it can make them lighter and less painful. There is no evidence that women on the combined pill put on any significant weight, although they may experience bloating at certain times in the course. Women on the pill require monitoring of their blood pressure. There are multiple different types of combined pills.
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This question is part of the following fields:
- Medicine
- Pharmacology
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Question 51
Incorrect
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At rest, proton pumps are sequestered within the parietal cell in a series of membrane compartments known as:
Your Answer: Canaliculi
Correct Answer: Tubulovesicles
Explanation:The gastric H, K-ATPase pump, which pumps gastric acid (HCl), in the resting state is found in cytoplasmic tubular membranes. In the stimulated state this pump moves from the tubulovesicles to the apical membrane.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 52
Correct
-
Neutrophils are attracted to an infected area by:
Your Answer: Chemokines
Explanation:The major role of chemokines is to act as a chemoattractant to guide the migration of cells like neutrophils to the site of infection.
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This question is part of the following fields:
- Immunology
- Medicine
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Question 53
Correct
-
Which enzyme is deficient in the inborn error of metabolism called galactosemia?
Your Answer: Galactose-1-phosphate uridyl transferase
Explanation:Galactosaemia is a rare genetic autosomal recessive metabolic disorder. Lactose is broken down by the enzyme lactase into glucose and galactose. In individuals with galactosemia, the enzymes needed for further metabolism of galactose (Galactose-1-phosphate uridyltransferase) are severely diminished or missing entirely, leading to toxic levels of galactose 1-phosphate in various tissues.
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This question is part of the following fields:
- Medicine
- Metabolism
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Question 54
Incorrect
-
A 20-year-old male presented to the clinic with a long term history of pins and needles sensation in both hands. He also has prognathism. He also gives a history of recent onset right upper quadrant pain after being started on a new medication for his condition. Which of the following medications acting on his endocrine system can be responsible for this adverse effect?
Your Answer: Levothyroxine
Correct Answer: Octreotide
Explanation:The patient (known case of acromegaly) seems to have developed cholelithiasis (presenting with right upper quadrant pain) probably due to octreotide.It is a long-acting analogue of somatostatin which is released from D cells of the pancreas and inhibits the release of growth hormone, glucagon, and insulin.Uses- Acute treatment of variceal haemorrhage- Acromegaly- Carcinoid syndrome- Prevent complications following pancreatic surgery- VIPomas- Refractory diarrhoeaAdverse effectsGallstones (secondary to biliary stasis)Other options:- Bromocriptine – a dopamine agonist with side effects arising from its stimulation of the brain vomiting centre.- Desmopressin – predominantly used in patients with diabetes insipidus by increasing the presence of aquaporin channels in the distal collecting duct to increase water reabsorption from the kidneys. The main side effects include headache and facial flushing due to hypertension.- Metformin – mainly reduces hepatic gluconeogenesis in patients with type 2 diabetes, common side effects include diarrhoea, vomiting, and lactic acidosis- Levothyroxine – synthetic thyroxine used in patients with hypothyroidism, common side effects result from incorrect dosing and mimic the symptoms of hyperthyroidism.
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This question is part of the following fields:
- Medicine
- Pharmacology
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Question 55
Correct
-
The primary sensory cortex is:
Your Answer: Brodmann area 3,1,2
Explanation:A Brodmann area in the brain is defined by cytoarchitecture, histology and organization of cells:Primary somatosensory cortex is areas 3,1, and 2Primary Motor 4Premotor 6Primary Visual 17Primary Auditory 41Brocas 44
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This question is part of the following fields:
- Medicine
- Neurology
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Question 56
Incorrect
-
Which vagus nerve mainly supplies the AV node?
Your Answer: Both left and right vagus
Correct Answer: Left vagus
Explanation:As the AV node develops from the left side of the embryo It is supplied by the left vagus nerve.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 57
Correct
-
The lower oesophageal sphincter is under neural control. Which of the following causes contraction of the intrinsic sphincter?
Your Answer: Acetylcholine
Explanation:The lower oesophageal sphincter (LOS) is a specific region of the oesophageal circular smooth muscle. It allows the passage of a food bolus to the stomach and prevents the reflux of gastric contents into the oesophagus. The tone of the LOS is myogenic in origin and depends on smooth muscle properties that lead to the opening of Ca2+ channels but can also be modulated by enteric motor neurons, the parasympathetic and sympathetic extrinsic nervous system and several neurohumoral substances. Nitric oxide causes LOS relaxation. Acetylcholine and tachykinins are involved in the LOS contraction.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 58
Incorrect
-
The alpha amylases hydrolyse which linkages in the ingested polysaccharides?
Your Answer: 4:1α linkages
Correct Answer: 1:4α linkages
Explanation:Alfa amylase hydrolyses the α (1-4) glyosidic bonds in amylose and amylopectin and leave primarily maltose.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 59
Correct
-
Activation of the cool receptor (CMR-1), causes:
Your Answer: Influx of Ca++ & Na+
Explanation:Cold and Menthol receptor 1 (CMR1) is a protein that in humans is encoded by TRPM8 gene. It is an ion channel which upon activation causes the influx of Na+ and Ca++ ions into the cell that leads to the depolarization and generation of an action potential.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 60
Correct
-
Lymphoid stem cells give rise to the following cells:
Your Answer: T cells, b cells and natural killer cells
Explanation:T Cells, B Cells and NK Cells (and all other Innate lymphoid cells) are unique to the lymphocyte family, but dendritic cells are not. Dendritic cells of identical appearance but different markers are spread throughout the body, and come from either lymphoid and myeloid lineages.
Myeloid stem cells lead to myeloblasts, which evolve into macrophages, monocytes, neutrophils, basophils, and eosinophils.
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This question is part of the following fields:
- Haematology
- Medicine
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Question 61
Incorrect
-
Why does arterial blood pressure drop during pregnancy?
Your Answer: Oestrogen relaxes vascular smooth muscle
Correct Answer: Progesterone relaxes vascular smooth muscle
Explanation:Progesterone relaxes vascular smooth muscle thus resulting In a decrease in total peripheral resistance. This accounts for the increase in the cardiac output.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 62
Correct
-
Which of the following antiarrhythmic drugs may be used in the treatment of long QT syndrome?
Your Answer: Atenolol
Explanation:Beta-blockers are the mainstay of treatment in long QT syndrome. Implantable cardioverter-defibrillators are the most effective treatment in genotypes with a high risk of recurrence.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 63
Correct
-
In Jugular vein pressure the “a” wave represents?
Your Answer: Atrial systole
Explanation:The jugular venous pressure (JVP, sometimes referred to as jugular venous pulse) is the indirectly observed pressure over the venous system via visualization of the internal jugular vein. It can be useful in the differentiation of different forms of heart and lung disease. Classically three upward deflections and two downward deflections have been described: The upward deflections are the a (atrial contraction), c (ventricular contraction and resulting bulging of tricuspid into the right atrium during isovolumetric systole) and v = venous filling.The downward deflections of the wave are the x (the atrium relaxes and the tricuspid valve moves downward) and the y descent (filling of ventricle after tricuspid opening).
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 64
Incorrect
-
A 62 year old female has complained she feels unsteady when she is walking. She is examined and is found to have pyramidal weakness of her left lower leg. She also has reduced pain and temperature sensation on her right leg and right side of her torso up to the umbilicus. Her joint position sense is also impaired in her left big toe but is found to be normal elsewhere. She has definite left extensor plantar response, and the right plantar response is equivocal. Where is the lesion?
Your Answer: Midline mid-thoracic cord
Correct Answer: Left mid-thoracic cord
Explanation:In Brown-Sequard syndrome, there is paralysis and loss of proprioception, which occurs on the same (ipsilateral) side of the body, as the lesion. Loss of pain and temperature sensation, therefore, occurs on the opposite (contralateral) side of the body as the lesion.
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This question is part of the following fields:
- Geriatrics
- Medicine
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Question 65
Incorrect
-
Which of the following does not lower ventricular rate in atrial fibrillation?
Your Answer: Acetylcholine
Correct Answer: Adrenaline
Explanation:Adrenaline is a sympathetic neurotransmitter which increases the heart rate. During atrial fibrillation the atria is contracting at more than 200 beats/min. Acetylcholine is a parasympathetic neurotransmitter decreasing the heart rate. Digital also depresses the conduction at the AV conduction. Vagal discharge and occulocardiac reflux decrease the heart rate and convert the tachycardia into normal sinus rhythm.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 66
Correct
-
Which of the following stimulates glucagon release?
Your Answer: Exercise
Explanation:Studies have shown a small increase in glucagon levels during stress tests and exercise. This occurs in response to the reduction of blood glucose levels during physical activity; epinephrine levels are also a stimulus for the release of glucagon during exercise, since it suppresses insulin, which accounts for its stimulatory effects on glucagon. The use of stored fats for energy during exercise also stimulates the release of glucagon.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 67
Correct
-
Immortality can result from over expression of which enzyme?
Your Answer: Telomerase
Explanation:Telomerase activity is seen in germ cells and is absent in somatic cells. Telomeres prevent the chromosomes from shortening and prevent the coding portion of the DNA from being lost, thus allowing the cell to replicate indefinitely.
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This question is part of the following fields:
- Genetics
- Medicine
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Question 68
Correct
-
Where does most fat digestion begin?
Your Answer: Duodenum
Explanation:Digestion of some fats can begin in the mouth where lingual lipase breaks down some short chain lipids into diglycerides. However fats are mainly digested in the small intestine (in the duodenum). The presence of fat in the small intestine produces hormones that stimulate the release of pancreatic lipase from the pancreas and bile from the liver which helps in the emulsification of fats for absorption of fatty acids.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 69
Correct
-
When observing a JVP, which of the following would lead to prominent v waves?
Your Answer: Tricuspid regurgitation
Explanation:The v wave corresponds to Venous filling when the tricuspid valve is closed and venous pressure increases from venous return. In Tricuspid regurgitation there is additional blood from the regurgitant flow and thus this leads to a more prominent V wave.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 70
Incorrect
-
A 14-year-old girl presents with short stature, webbed neck and primary amenorrhoea.Given the likely clinical diagnosis, which hormone replacement is most crucial over the longer term?
Your Answer: Pulsatile GNRH
Correct Answer: Oestrogen
Explanation:This girl most likely has Turner syndrome (TS) also known as 45,X, a condition in which a female is partly or completely missing an X chromosome. Signs and symptoms vary among those affected. Often, a short and webbed neck, low-set ears, low hairline at the back of the neck, short stature, and swollen hands and feet are seen at birth. Typically, they are without menstrual periods, do not develop breasts, and are unable to have children. Heart defects, diabetes, and low thyroid hormone occur more frequently. Most people with TS have normal intelligence. Many, however, have troubles with spatial visualization such as that needed for mathematics. Vision and hearing problems occur more often. Turner syndrome is not usually inherited from a person’s parents. No environmental risks are known and the mother’s age does not play a role. As a chromosomal condition, there is no cure for Turner syndrome. However, much can be done to minimize the symptoms including prescribing growth hormone, either alone or with a low dose of androgen, and oestrogen replacement therapy which is crucial long term for maintaining good bone integrity, cardiovascular health and tissue health
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 71
Correct
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Question 72
Correct
-
Calcium induced calcium release occurs in the sarcoplasmic reticulum by activation of which receptors
Your Answer: Ryanodine receptors
Explanation:Calcium-induced calcium release (CICR) describes a biological process whereby calcium is able to activate calcium release from intracellular Ca2+ stores (e.g., endoplasmic reticulum or sarcoplasmic reticulum). CICR occurs when the resulting Ca2+ influx activates ryanodine receptors on the SR membrane, which causes more Ca2+ to be released into the cytosol.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 73
Correct
-
Select the correct pairing regarding the surface of the cerebral hemispheres.
Your Answer: Parietal lobe : primary somatosensory cortex
Explanation:Parietal lobe: The primary somatosensory cortex is located in the postcentral gyrus of the parietal lobe. It is responsible for processing sensory information from the body.
Frontal lobe: The primary motor cortex is located in the precentral gyrus of the frontal lobe. The frontal lobe also contains the premotor cortex, which is involved in planning movements. The primary visual cortex is located in the occipital lobe, not the frontal lobe.
Temporal lobe: The primary auditory cortex is located in the superior temporal gyrus of the temporal lobe. The primary motor and premotor cortices are located in the frontal lobe, not the temporal lobe.
Occipital lobe: The primary visual cortex is located in the occipital lobe. The primary auditory cortex is located in the temporal lobe, not the occipital lobe.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 74
Correct
-
A 85 year old male with a history of faecal impaction, who lived at a nursing-home presented with abdominal pain and distension, confusion and agitation. Which of the following is the first step of the management.
Your Answer: Phosphate enema
Explanation:The most probable cause for this presentation is faecal impaction following constipation, which is common among old people who live in nursing-homes. There can be number of reason for constipation in old age, including medications, endocrine and metabolic diseases, neurologic disorders, myopathic disorders, dietary habits etc. Enemas are a way of removing impacted faeces, which helps rectal evacuation.
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This question is part of the following fields:
- Geriatrics
- Medicine
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Question 75
Correct
-
Which one of the following cells originates from a monocyte and resembles a macrophage?
Your Answer: Microglia
Explanation:Microglia act as the macrophages of the central nervous system, and they contribute to innate and adaptive immune responses. Studies have shown that microglial cells recognize monocyte antigens, and there are similarities between them that demonstrate that they originate from these monocytes.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 76
Correct
-
A 27-year-old female diagnosed with rheumatoid arthritis has failed to respond to methotrexate and sulfasalazine. Her GP decides to start her on etanercept injections. Which one among the following is an adverse effect associated with the use of etanercept?
Your Answer: Reactivation of tuberculosis
Explanation:Among the give options, reactivation of tuberculosis may occur in a patient under treatment with etanercept.Etanercept is a biological TNF inhibit commonly used to control ankylosing spondylitis, juvenile idiopathic arthritis, plaque psoriasis, psoriatic arthritis, and rheumatoid arthritis.Etanercept is a soluble receptor that binds both TNF-alpha and TNF-beta to inhibit the inflammatory response in joints and skin that is characteristic of these autoimmune disorders.The most common adverse effects include infections (viral, bacterial, and fungal – mostly upper respiratory tract infections) and injection site reaction (erythema, itching, pain, swelling, bleeding, bruising).Rarely it can also cause, reactivation of hepatitis B and TB, pneumocystis pneumonia, congestive cardiac failure, Steven-Johnson syndrome, toxic epidermal necrolysis, etc.
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This question is part of the following fields:
- Medicine
- Pharmacology
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Question 77
Correct
-
The neurotransmitter utilised by the Purkinje cells is:
Your Answer: GABA
Explanation:The cerebellar cortex consist of 3 layers: the molecular layer, the granular cell layer and the Purkinje cell layer. Purkinje cells play a fundamental role in controlling motor movement. They release a neurotransmitter called GABA (gamma-aminobutyric acid) which exerts inhibitory actions thereby reducing transmission of impulses. These inhibitory functions enable purkinje cells to regulate and coordinate motor movements.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 78
Correct
-
Question 79
Correct
-
An 18 year old girl presents with short history of marked, right hip pain and an associated limp. She has a history of acute lymphoblastic leukaemia for which she completed treatment for last six months.
Your Answer: Avascular necrosis of the femoral head
Explanation:Avascular necrosis (AVN) of the femoral head is a pathological process that results from disruption of the blood supply to the bone and occurs most commonly in the femoral epiphysis. Patients usually present with pain and limited joint motion. The mechanism involves impaired circulation to a specific area that ultimately becomes necrotic. AVN is most frequently associated with high doses of oral and intravenous corticosteroids and prolonged duration of therapy. Cancer patients receiving chemotherapy are usually also treated with corticosteroids.
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This question is part of the following fields:
- Connective Tissue
- Medicine
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Question 80
Correct
-
Which enzyme deficiency causes Beriberi?
Your Answer: Thiamine
Explanation:Beriberi refers to a cluster of symptoms caused primarily by thiamine (vitamin B1) deficiency. Symptoms of beriberi include weight loss, emotional disturbances, impaired sensory perception, weakness and pain in the limbs, and periods of irregular heart rate.
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This question is part of the following fields:
- Haematology
- Medicine
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Question 81
Incorrect
-
Which of the following is NOT a component of bile?
Your Answer: Electrolytes
Correct Answer: Unconjugated bilirubin
Explanation:The composition of gallbladder bile is 97% water, 0.7% bile salts, 0.2% bilirubin, 0.51% fats (cholesterol, fatty acids and lecithin), and 200 meq/l inorganic salts (electrolytes).
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 82
Correct
-
The hyperpolarization phase of pacemaker cells is dominated by ____ current.
Your Answer: K+
Explanation:The hyperpolarization phase is a continuation of the repolarization phase but the membrane potential dips below the resting membrane potential. This results due to the fact that the K+ channels take a longer time to close than the Na+ channels. Hence efflux of the K+ will result in hyperpolarization.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 83
Incorrect
-
Where does secretin work in the pancreas?
Your Answer: Acinar cells
Correct Answer: Pancreatic ducts
Explanation:Secretin, a hormone produced by the duodenal S cells in response to the stomach chyme containing high hydrogen atom concentration (high acidity), is released into the blood stream; upon return to the digestive tract, secretion decreases gastric emptying, increases secretion of the pancreatic ductal cells, as well as stimulating pancreatic acinar cells to release their zymogenic juice.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 84
Correct
-
Regarding blood supply to the heart;
Your Answer: Coronary arteries fill as the heart relaxes
Explanation:The heart muscles acts like the skeletal muscle in the fact that it also compress the vessels during contraction. As the pressure in the ventricle is slightly greater than in the aorta the coronary vessels collapse during systole. Blood flows through them during the diastole phase of contraction.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 85
Incorrect
-
Presence of which of the following indicates a worse prognosis in rheumatoid arthritis?
Your Answer: Being a smoker
Correct Answer: Anti-CCP antibodies
Explanation:Rheumatoid arthritis is both common and chronic, with significant consequences for multiple organ systems. Anti-cyclic citrullinated peptide (anti-CCP) antibody testing is particularly useful in the diagnosis of rheumatoid arthritis, with high specificity, presence early in the disease process, and ability to identify patients who are likely to have severe disease and irreversible damage. However, its sensitivity is low, and a negative result does not exclude disease. Anti-CCP antibodies have not been found at a significant frequency in other diseases to date, and are more specific than rheumatoid factor for detecting rheumatoid arthritis. The other factors that are mentioned do not play a key prognostic role.
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This question is part of the following fields:
- Connective Tissue
- Medicine
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Question 86
Correct
-
With regards to the cell cycle, which phase represents period of cell growth that divides the end of DNA synthesis and the beginning of somatic cell division?
Your Answer: Gap 2
Explanation:Interphase is divided into three phases: G1 (first gap), S (synthesis), and G2 (second gap). During all three parts of interphase, the cell grows by producing proteins and cytoplasmic organelles. However, chromosomes are replicated only during the S phase. Thus, a cell grows (G1), continues to grow as it duplicates its chromosomes (S), grows more and prepares for mitosis (G2), and finally divides (M) before restarting the cycle.
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This question is part of the following fields:
- Cell Biology
- Medicine
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Question 87
Correct
-
Which of the following is a product of D cells
Your Answer: Somatostatin
Explanation:Somatostatin is secreted by D cells, HCL and intrinsic factor secreted by parietal cells. Trefoil peptides are secreted by mucus secreting goblet cells and gastrin releasing peptide (grp) by post-ganglionic fibers of the vagus nerve (which innervate the G cells of the stomach).
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 88
Incorrect
-
The Plateau phase in myocyte action potentials does all of the following except:
Your Answer: It results from an Ca2+ influx
Correct Answer: It allows early reactivation of the myocytes
Explanation:The presence of the plateau in the action potential causes ventricular contraction to last as much as 15 times longer in cardiac muscle as in skeletal muscle. The plateau phase which follows is unique to myocytes and results from a small, but sustained inward calcium current through L-type calcium channels lasting 200-400 ms. This calcium influx is caused by a combined increase in permeability of the cell and especially the sarcolemmal membranes to calcium. This plateau (refractory) phase prevents early reactivation of the myocytes and directly determines the strength of contraction.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 89
Incorrect
-
Water hammer pulse is found in:
Your Answer: Aortic stenosis
Correct Answer: Aortic insufficiency
Explanation:Watson’s water hammer pulse is the medical sign which describes a pulse that is bounding and forceful, rapidly increasing and subsequently collapsing, as if it were the sound of a water hammer that was causing the pulse. A water hammer was a Victorian toy in which a tube was half filled with fluid, the remainder being a vacuum. The child would invert and reinvert the tube; each time the impact of the fluid at each end would sound like a hammer blow. This is associated with increased stroke volume of the left ventricle and decrease in the peripheral resistance leading to the widened pulse pressure of aortic regurgitation.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 90
Incorrect
-
A 52-year-old man has squamous-cell carcinoma of his lower lip. Which of the following is most likely to be a feature of this type of carcinoma?
Your Answer: It commonly spreads to distant sites by venous channels
Correct Answer: It is capable of metastasising via the lymphatics
Explanation:Squamous-cell skin cancer usually presents as a hard lump with a scaly top but can also form an ulcer. Onset is often over months and it is more likely to spread to distant areas than basal cell cancer vie the lymphatics. The greatest risk factor is high total exposure to ultraviolet radiation from the Sun. Other risks include prior scars, chronic wounds, actinic keratosis, lighter skin, Bowen’s disease, arsenic exposure, radiation therapy, poor immune system function, previous basal cell carcinoma, and HPV infection. While prognosis is usually good, if distant spread occurs five-year survival is ,34%
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This question is part of the following fields:
- Dermatology
- Medicine
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Question 91
Correct
-
Which of the flowing plasma proteins has the greatest affinity for T4?
Your Answer: Thyroxin-binding globulin
Explanation:There are three principal plasma thyroid hormone-binding proteins, thyroxine-binding globulin (TBG), transthyretin (TTR), and albumin. TBG is synthesized in the liver and due to its relatively high affinity for iodothyronines, binds and carries approximately 70–75% of circulating T4 and T3.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 92
Incorrect
-
Which receptor type is associated with the inhibition of pancreatic endocrine secretion?
Your Answer: Β1
Correct Answer: Α2
Explanation:The activation of alpha 2-adrenergic receptors in pancreatic beta-cells works by inhibiting the secretion of insulin.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 93
Incorrect
-
Concerning the functional unit of the liver, which segment is most susceptible to hypoxic damage?
Your Answer: Zone 1
Correct Answer: Zone 3
Explanation:From a metabolic perspective, the functional unit is the hepatic acinus (terminal acinus), each of which is centred on the line connecting two portal triads and extends outwards to the two adjacent central veins. The periportal zone I is nearest to the entering vascular supply and receives the most oxygenated blood, making it least sensitive to ischemic injury while making it very susceptible to viral hepatitis. Conversely, the centrilobular zone III has the poorest oxygenation, and will be most affected during a time of ischemia.
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This question is part of the following fields:
- Hepatobiliary
- Medicine
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Question 94
Correct
-
If O2 makes up 21% of air, then at one atmosphere (760mmHg) it would be expected that the PO2 of inspired air should be 0,21 x 760 = 160mmHg. In the alveoli the actual measure is 149mmHg because…
Your Answer: Water is equilibrated with air
Explanation:There are several factors that determine the value of alveolar partial oxygen pressure including: the pressure of outside air, the partial pressure of inspired oxygen and carbon dioxide, the rates of total body oxygen consumption and carbon dioxide production, the rates of alveolar ventilation and perfusion. The alveolar partial pressure is lower than the atmospheric oxygen partial pressure. One reason is, as the air enters the lungs, it is humidified by the upper airway and thus the partial pressure of water vapour reduces the oxygen partial pressure as water is equilibrated with air.
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This question is part of the following fields:
- Medicine
- Respiratory
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Question 95
Incorrect
-
A 56 year old woman taking procainamide develops drug induced erythematosus. Which of the following features is the most characteristic of this condition?
Your Answer: It commonly involves the kidneys
Correct Answer: It may occur with chlorpromazine
Explanation:Drug induced lupus is usually positive for antinuclear and antihistone antibodies, typically without renal or neurologic involvement. However, pulmonary involvement is common. Drugs that can induce lupus include isoniazid, hydralazine, procainamide, chlorpromazine, and other anticonvulsants.
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This question is part of the following fields:
- Connective Tissue
- Medicine
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Question 96
Incorrect
-
Which glucose transporter is responsible for the uptake of dietary glucose from the gut?
Your Answer: SGLT2
Correct Answer: SGLT1
Explanation:SGLT 1 is responsible for the uptake of glucose via secondary active transport from the small intestine and the renal tubules.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 97
Incorrect
-
Question 98
Correct
-
Question 99
Incorrect
-
The ENaC Transporter occurs in which part of the renal tubule?
Your Answer: Basolateral surface of thick ascending limb
Correct Answer: Collecting duct
Explanation:The epithelial sodium channel (ENaC) is a membrane-bound ion channel that is selectively permeable to Na+ ions. It is involved primarily in the reabsorption of sodium ions at the collecting ducts of the kidney’s nephrons.
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This question is part of the following fields:
- Medicine
- Renal
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Question 100
Incorrect
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Which of the following factors is not completely produced in the liver?
Your Answer: Factor ix
Correct Answer: Factor viii
Explanation:Factor VIII is produced in liver sinusoidal cells and endothelial cells outside of the liver throughout the body. This protein circulates in the bloodstream in an inactive form, bound to another molecule called von Willebrand factor, until an injury that damages blood vessels occurs.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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SESSION STATS - PERFORMANCE PER SPECIALTY
