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Question 1
Incorrect
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The pontine tegmentum as part of the midbrain, contains which cranial nerve nuclei?
Your Answer: CN 3, 4, 6
Correct Answer: CN 5 to 8
Explanation:The pontine tegmentum also known as dorsal pons is located within the brain stem. Several cranial nerve nuclei are located in the pontine tegmentum. The nuclei of CN V, CN VI, CN VII and CNVIII are located in the pontine tegmentum.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 2
Correct
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Which one of the following ECG findings is least associated with digoxin use?
Your Answer: Prolonged QT interval
Explanation:Digoxin ECG features:• ST depression (‘reverse tick’)• flattened/inverted T waves• Prolonged PR interval• short QT interval• arrhythmias e.g. AV block, bradycardia, ventricular tachycardia or fibrillation (for example paroxysmal atrial tachycardia with A-V block – so-called PAT with block) is said to be pathognomonic (i.e. diagnostic) of digoxin toxicity.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 3
Incorrect
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Choose the correct answer: fibers in the superior cerebellar peduncle:
Your Answer: Are mainly dorsal spinocerebellar tracts to the cerebellum
Correct Answer: Are mainly ventral spinocerebellar tracts from the cerebellar nuclei to the thalamus and red nucleus
Explanation:There are three cerebellar peduncles with different connections and functions. The three are mainly, superior, middle and inferior. The superior cerebellar peduncle is also known as the “Brachium conjunctivum”. It predominantly contains efferent fibers from the cerebellar nuclei, as well as some afferents from the spinocerebellar tract. The efferent pathways include cerebellorubral, dentatothalamic, and fastigioreticular fibers. These are tracts projecting from the deep cerebellar nuclei to the thalamus and red nucleus. The middle cerebellar peduncle connects to the pontine nucleus and the dorsal spinocerebellar tracts run through the superior cerebellar peduncle.
The superior cerebellar peduncle contains vital afferent and efferent fibers including cerebellothalamic, cerebellorubral and ventrospinocerebellar tracts.
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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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The interior of lysosomes is kept at a pH of around 5 by the action of:
Your Answer: H+ ATPase
Explanation:The lysosome maintains its pH differential by pumping in protons (H+ ions) from the cytosol across the membrane via proton pumps and chloride ion channels. Vacuolar H+-ATPases are responsible for transport of protons, while the counter transport of chloride ions is performed by ClC-7 Cl−/H+ antiporter.
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This question is part of the following fields:
- Cell Biology
- Medicine
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Question 5
Incorrect
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The ‘c’ wave in JVP corresponds more closely with:
Your Answer: Closure of mitral valve
Correct Answer: Isovolumetric contraction
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 (peaks) and two downward deflections (troughs) 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 6
Correct
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Which mechanism of action do Quinolones use?
Your Answer: Inhibit DNA gyrase
Explanation:The quinolones are a family of synthetic broad-spectrum antibiotic drugs. Quinolones exert their antibacterial effect by preventing bacterial DNA from unwinding and duplicating.
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This question is part of the following fields:
- Infectious Diseases
- Medicine
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Question 7
Incorrect
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Regarding bronchial innervation which of the following is correct:
Your Answer: Beta 2 receptors decrease bronchial secretions
Correct Answer: Alpha 1 receptors increase bronchial constriction
Explanation:Stimulation of β2 receptors results in smooth muscle relaxation and bronchodilation. α1 receptors cause smooth muscle contraction in the bronchioles although minor to the β2 effects.
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This question is part of the following fields:
- Medicine
- Respiratory
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Question 8
Incorrect
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In addition to its role in digestion and absorption of fats, bile:
Your Answer: Causes stones
Correct Answer: Is the major excretory route for lipid-soluble waste products
Explanation:The end product of haem metabolism is bilirubin and jaundice is caused by increased bilirubin levels in the blood. Gallstones are mainly caused by cholesterol and bile pigments. Bile is the main route of excretion for lipid soluble waste products whereas urine is the main route of excretion of water soluble waste products.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 9
Incorrect
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Among the following which is the beneficial effect of nitro-glycerine?
Your Answer: Reduces sodium potassium transport in myocardial muscle
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.
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This question is part of the following fields:
- Medicine
- Pharmacology
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Question 10
Correct
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What is the primary problem of achalasia
Your Answer: Deficiency of myenteric plexus at the lower oesophageal sphincter
Explanation:Oesophageal achalasia is an oesophageal motility disorder involving the smooth muscle layer of the oesophagus is characterized by the failure of the lower oesophageal sphincter (LES) relaxation and aperistalsis, caused primarily by the loss of the inhibitory innervation of the oesophageal myenteric plexus.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 11
Incorrect
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The process by which DNA fragments are separated by gel and transferred onto a membrane sheet is called:
Your Answer: Northern blotting
Correct Answer: Southern blotting
Explanation:A Southern blot is a method used in molecular biology for detection of a specific DNA sequence in DNA samples. Southern blotting combines transfer of electrophoresis-separated DNA fragments to a filter membrane and subsequent fragment detection by probe hybridization. The other forms of blotting involve the use of RNA and proteins.
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This question is part of the following fields:
- Genetics
- Medicine
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Question 12
Correct
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Calcium is mobilized from the sarcoplasmic reticulum through:
Your Answer: Ryanodine receptor (RyR2) calcium release channels
Explanation:During the plateau phase of the action potential, calcium from the extracellular fluid enters through the L type of calcium channels. This entry triggers the release of more calcium from the sarcoplasmic reticulum via the ryanodine receptors. As a result intracellular calcium increases binding to troponin C resulting in contraction.
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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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Which of the following is not secreted by cells in the antrum of the stomach?
Your Answer: Hydrochloric acid
Explanation:Cells in the body of the stomach secrete mucus, HCl and pepsinogen. Cells in the antrum secrete pepsinogen, gastrin and mucus.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 14
Incorrect
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All of the following are consistent with the indicator dilution method except---
Your Answer: The indicator must have no haemodynamic effects
Correct Answer: In thermodilution, the indicator used is warm saline
Explanation:In thermodilution, the indicator used is cold saline.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 15
Incorrect
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B1 adrenergic stimulation produces:
Your Answer: Negative inotropy
Correct Answer: Increase in calcium cytosolic concentration
Explanation:Norepinephrine secreted by the sympathetic endings binds to B1 receptors, and the resulting increase in intracellular cAMP facilitates the opening of L channels, increasing Ica and the rapidity of the depolarization phase of the impulse and activates PKA which leads to phosphorylation of the voltage-gated Ca2+ channels, causing them to spend more time in the open state.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 16
Incorrect
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Pacemaker cells in the SA node and the AV node are connected by?
Your Answer: C cells
Correct Answer: Gap junctions
Explanation:Gap junctions allows for rapid propagation of the action potential from one cell to the other. The cells of the heart are connected by gap junctions.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 17
Correct
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The mechanism of action of low molecular weight heparin, has the greatest effect on which of the following components of the coagulation cascade?
Your Answer: Factor Xa
Explanation:Mechanism of action of low molecular weight heparin (LMWH): It inhibits coagulation by activating antithrombin III. Antithrombin III binds to and inhibits factor Xa. In doing so it prevents activation of the final common path; Xa inactivation means that prothrombin is not activated to thrombin, thereby not converting fibrinogen into fibrin for the formation of a clot. LMHW is a small fragment of a larger mucopolysaccharide, heparin. Heparin works similarly, by binding antithrombin III and activating it. Heparin also has a binding site for thrombin, so thrombin can interact with antithrombin III and heparin, thus inhibiting coagulation. Heparin has a faster onset of anticoagulant action as it will inhibit not only Xa but also thrombin, while LMWH acts only on Xa inhibition.Compared to heparin, LMWHs have a longer half-life, so dosing is more predictable and can be less frequent, most commonly once per day.Dosage and uses:LMWH is administered via subcutaneous injection. This has long-term implications on the choice of anticoagulant for prophylaxis, for example, in orthopaedic patients recovering from joint replacement surgery, or in the treatment of DVT/PE.Adverse effects:The main risk of LMWH will be bleeding. The specific antidote for heparin-induced bleeding is protamine sulphate.Less commonly it can cause:Heparin-induced thrombocytopenia (HIT)Osteoporosis and spontaneous fracturesHypoaldosteronismHypersensitivity reactions
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This question is part of the following fields:
- Medicine
- Pharmacology
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Question 18
Incorrect
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Which membrane bound protein in the sarcoplasmic reticulum regulates calcium return from the cytosol to the sarcoplasmic reticulum?
Your Answer: Troponin i
Correct Answer: Phospholamban
Explanation:Phosphorylation of phospholamban 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 sarcoplasmic reticulum (SR), that controls the rate of uptake of calcium into the SR. The latter effect explains enhanced relaxation (lusitropic effect).
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 19
Incorrect
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On a mountain the atmospheric pressure is 700 mmHg and the humidity close to zero, the partial pressure of oxygen is:
Your Answer: 100 mmHg
Correct Answer: 147 mmHg
Explanation:Natural air includes approximately 21% of oxygen. If humidity is zero, the partial pressure of oxygen is 700 × 21% = 147 mmHg
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This question is part of the following fields:
- Medicine
- Respiratory
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Question 20
Incorrect
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The basic unit of contraction in myocytes is:
Your Answer: Troponin
Correct Answer: Sarcomere
Explanation:Sarcomere is the organelle where calcium is stored to be released during contraction of the muscle. It is the basic unit of contraction in striated muscle fibers. As myocytes are also striated muscles, sarcomeres also forms the basic unit of contraction. The impulses travel along the membrane and via its interaction with the dihydropyridine receptors it releases the stored calcium.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 21
Incorrect
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Which one of the following will increase an individual’s appetite?
Your Answer: Peptide yy
Correct Answer: Ghrelin
Explanation:Ghrelin is a hormone which exerts a strong influence on hunger and energy balance. It helps regulate appetite by being secreted when the stomach is empty, to stimulate hunger. When the stomach is filled, its secretion stops.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 22
Incorrect
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Calcium is transported over the brush border in the gut, via which transporter / channel?
Your Answer: Calcium / Na+ exchanger
Correct Answer: TRPV 6
Explanation:Transient Receptor Potential Vanilloid 6 or TRPV 6 is a calcium channel located in the cell membrane which is present in a variety of organs, including small intestine, oesophagus, stomach, colon, placenta, kidney, and uterus. In the intestine, it is located in the apical brush-border membrane of the enterocyte, regulating the entry of calcium into the cell.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 23
Incorrect
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Regarding the length of systole and diastole which of the following is true?
Your Answer: Cardiac muscle can be tetanise
Correct 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 24
Incorrect
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Neutrophils are key components of the innate immune system. They contain numerous primary and secondary granules involved in killing and digesting microorganisms. With regard to defensins, they are:
Your Answer: Involved in the breakdown of fibrous structures in the extracellular matrix
Correct Answer: Naturally occurring cysteine-rich antibacterial and antifungal polypeptides
Explanation:Cationic antimicrobial peptides, including defensins, cathelicidins, and thrombocidins, provide important initial defences against invading microbes. These peptides bind the bacterial membrane and form pores, killing the bacterium by hypo-osmotic lysis.
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This question is part of the following fields:
- Immunology
- Medicine
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Question 25
Incorrect
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Sympathetic supply to the stomach is derived from
Your Answer: T8-T12 spinal segments via the coeliac ganglion
Correct Answer: T5-T9 spinal segments via the coeliac ganglion
Explanation:Parasympathetic innervation to the stomach is from the vagus nerve and the sympathetic innervation is from the T5-T9 spinal segments via the coeliac ganglion through the greater splanchnic nerve.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 26
Incorrect
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Mutation in RB can lead to the formation of which cancer?
Your Answer: Breast cancer
Correct 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 27
Incorrect
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The choroid plexus:
Your Answer: One of its main functions is to produce CSF
Correct Answer: All are true
Explanation:The choroid plexus is a vascular structure found in all cerebral ventricles. The functional unit of the choroid plexus, composed of a capillary, enveloped by a layer of differentiated ependymal epithelium. Unlike the capillaries that form the blood-brain barrier, choroid plexus capillaries are fenestrated and have no tight junctions. The endothelium, therefore, does not form a barrier to the movement of small molecules. Instead, the blood-CSF barrier at the choroid plexus is formed by the epithelial cells and the tight junctions that link them.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 28
Incorrect
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Which clotting factor is responsible for stabilization of the fibrin clot by formation of covalent cross-linkages?
Your Answer: Factor XIIa
Correct Answer: Factor XIIIa
Explanation:Factor XIII or fibrin stabilizing factor is an enzyme of the blood coagulation system that crosslinks fibrin. Deficiency of this factor (FXIIID) affects clot stability.
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This question is part of the following fields:
- Haematology
- Medicine
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Question 29
Incorrect
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A 72 year old female, known with rheumatoid arthritis for last 17 years, presents with recurrent attacks of red eyes with a sensation of grittiness. Which of the following is most likely cause of the red eyes?
Your Answer: keratitis
Correct Answer: keratoconjunctivitis sicca
Explanation:Rheumatoid arthritis is an inflammatory systemic disease associated with some extraarticular manifestations. Keratoconjunctivitis sicca, episcleritis, scleritis, corneal changes, and retinal vasculitis are the most common ocular complications among extraarticular manifestations of RA. The overall prevalence of keratoconjunctivitis sicca also known as dry eye syndrome among patients of RA is 21.2% and is the most common with sense of grittiness in the eyes.
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This question is part of the following fields:
- Connective Tissue
- Medicine
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Question 30
Correct
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Coronary flow is reduced during
Your Answer: Tachycardia
Explanation:Maximum amount of blood flow in the coronary arteries occur during diastole. When the heart rate increases which is also called tachycardia the duration of diastole decreases. Hence the amount of blood flow to the cardiac muscle also decreases.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 31
Incorrect
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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: Urinary incontinence
Correct 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 32
Incorrect
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Which of the following hormones would stimulate secretion of TSH?
Your Answer: Glucocorticoids
Correct Answer: TRH
Explanation:Thyrotropin-releasing hormone, also known as TRH, thyrotropin-releasing factor, TRF is a hormone produced by the hypothalamus. It functions as a releasing hormone, promoting the production of thyroid-stimulating hormone or thyrotropin and prolactin.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 33
Incorrect
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What is the function of the pro-apoptotic Bcl-2 family of proteins, Bax and Bak?
Your Answer: Stimulates the intracellular release of lysosomal contents
Correct Answer: Form permissive pores in the mitochondrial membrane
Explanation:The pro-apoptotic proteins in the BCL-2 family, including Bax and Bak, normally act on the mitochondrial membrane to promote permeabilization and release of cytochrome C and ROS, that are important signals in the apoptosis cascade. Growing evidence suggests that activated BAX and/or Bak form an oligomeric pore, MAC in the mitochondrial outer membrane. This results in the release of cytochrome c and other pro-apoptotic factors from the mitochondria, often referred to as mitochondrial outer membrane permeabilization, leading to activation of caspases.
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This question is part of the following fields:
- Cell Biology
- Medicine
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Question 34
Incorrect
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Protozoa is part of which pathogenic group?
Your Answer: Bacteria
Correct Answer: Eukaryotes
Explanation:Protozoa are a diverse group of unicellular eukaryotic organisms. Historically, protozoa were defined as single-celled organisms with animal-like behaviours, such as motility and predation.
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This question is part of the following fields:
- Infectious Diseases
- Medicine
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Question 35
Incorrect
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Colipase is secreted in an inactive form. Its activation in the intestinal lumen is by
Your Answer: Carboxypeptidase a
Correct Answer: Trypsin
Explanation:The enzyme trypsin exists in pancreatic juice in the inactive form trypsinogen, it is activated by the intestinal enterokinase in intestinal juice. Trypsin can then activate other protease enzymes and catalyse the reaction pro-colipase → colipase. Colipase is necessary, along with bile salts, to enable lipase function.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 36
Incorrect
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The process by which depolarization of the muscle fiber initiates contraction is called?
Your Answer: Dystrophin-glycoprotein coupling
Correct Answer: Action potential
Explanation:This process is known as an action potential. Upon generation of an action potential when depolarization reaches threshold, it spreads throughout the muscle fiber, resulting in generation of an excitation-contraction coupling leading to contraction of the muscle.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 37
Correct
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Café-au-lait spots are seen in each of the following, except:
Your Answer: Friedreich's ataxia
Explanation:Café-au-lait spots are hyperpigmented lesions that vary in colour from light brown to dark brown, with borders that may be smooth or irregular.
Causes include:
- Neurofibromatosis type I
- McCune–Albright syndrome
- Legius syndrome
- Tuberous sclerosis
- Fanconi anaemia
- Idiopathic
- Ataxia-telangiectasia
- Basal cell nevus syndrome
- Benign congenital skin lesion
- Bloom syndrome
- Chediak-Higashi syndrome
- Congenital nevus
- Gaucher disease
- Hunter syndrome
- Maffucci syndrome
- Multiple mucosal neuroma syndrome
- Noonan syndrome
- Pulmonary Stenosis
- Silver–Russell syndrome
- Watson syndrome
- Wiskott–Aldrich syndrome
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This question is part of the following fields:
- Dermatology
- Medicine
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Question 38
Incorrect
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Transport of Iron into enterocytes occurs via which membrane transporter?
Your Answer: Fe2+ / h+ pump
Correct Answer: Divalent metal transporter 1(dmt1)
Explanation:To be absorbed, dietary iron can be absorbed as part of a protein such as haem protein or iron must be in its ferrous Fe2+ form. A ferric reductase enzyme on the enterocytes’ brush border, duodenal cytochrome B (Dcytb), reduces ferric Fe3+ to Fe2+. A protein called divalent metal transporter 1 (DMT1), which can transport several divalent metals across the plasma membrane, then transports iron across the enterocyte’s cell membrane into the cell.
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This question is part of the following fields:
- Haematology
- Medicine
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Question 39
Incorrect
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The enzyme that catalyses the final step in glycogen synthesis is:
Your Answer: Lipase
Correct Answer: Glycogen synthase
Explanation:Glycogen synthase is a key enzyme in glycogenesis, the conversion of glucose into glycogen. This enzyme combines excess glucose residues one by one into a polymeric chain for storage as glycogen.
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This question is part of the following fields:
- Medicine
- Metabolism
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Question 40
Incorrect
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Which one of the following transporters is involved in facilitated diffusion?
Your Answer: Na+-linked glucose transport
Correct Answer: GLUT2
Explanation:GLUT 2 is a bidirectional transporter, allowing glucose to flow in 2 directions via facilitated diffusion. Is expressed by renal tubular cells, liver cells and pancreatic beta cells. It is also present in the basolateral membrane of the small intestine epithelium.
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This question is part of the following fields:
- Cell Biology
- Medicine
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Question 41
Incorrect
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Which one of the following is most likely to be seen in a patient with multiple endocrine neoplasia (MEN) type I?
Your Answer: Medullary thyroid carcinoma
Correct Answer: Insulinoma
Explanation:Multiple endocrine neoplasia type 1 (MEN-1 syndrome) or Wermer’s syndrome is part of a group of disorders, the multiple endocrine neoplasias, that affect the endocrine system through development of neoplastic lesions in the ‘three P’s’:Parathyroid (>90%): hyperparathyroidism due to parathyroid hyperplasiaPituitary (15-42%)Pancreas (60-70%, e.g. insulinoma, gastrinoma)
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 42
Correct
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Eosinophils provide immunity against
Your Answer: Multi cellular parasites
Explanation:Eosinophils, are a variety of white blood cells and one of the immune system components responsible for combating multicellular parasites and certain infections in vertebrates.
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This question is part of the following fields:
- Immunology
- Medicine
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Question 43
Incorrect
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Which of the following structures lie in close proximity to the thyroid?
Your Answer: 2 pairs of parathyroid glands.
Correct Answer: All of the options
Explanation:The thyroid gland receives its blood supply from the inferior and superior thyroid arteries. The recurrent laryngeal nerves emerges from the superior thoracic outlet bounded in part by the thyroid lobe. Two pairs of parathyroid glands lie near the thyroid. The common carotid artery splits into its external and internal branches at the upper border of the thyroid cartilage; these branches are separated by the gland.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 44
Correct
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A 26 year old male presents with right sided elbow and wrist pain and left sided knee and ankle pain that has persisted for about two weeks. He recently returned from a trip to Thailand that last for two weeks. The patient admits to having unprotected sex while on holiday. Examination reveals swelling and tenderness of tendons around joints but no inflammation of the joints. A vesiculopustular skin rash is also observed. What is the most likely cause?
Your Answer: Gonococcal arthritis
Explanation:Patients with disseminated gonococcal arthritis may present with dermatitis-arthritis syndrome (60%) of with localized septic arthritis. (40%). Arthritis-dermatitis syndrome includes the classic triad of dermatitis, tenosynovitis, and migratory polyarthritis. Gout usually involves a singe joint and does not cause vesicopustular skin rash. Reactive arthritis has ocular symptoms (conjunctivitis), urethritis, and arthritis. Fungal arthritis occurs rarely and it may occur after a surgical infection or fungal spread hematogenously. it presents with tender, red, hot and swollen joint with loss of range of motion.
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This question is part of the following fields:
- Connective Tissue
- Medicine
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Question 45
Incorrect
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Which one of the following neurotransmitters is considered a monoamine?
Your Answer: Acetylcholine
Correct Answer: Dopamine
Explanation:Monoamines are a class of neurotransmitters that include:
- Dopamine: A neurotransmitter involved in reward, motivation, and motor control.
- Norepinephrine: A neurotransmitter involved in arousal, attention, and stress responses.
- Serotonin: Although not listed in the options, it is another key monoamine involved in mood regulation.
The other neurotransmitters listed are not monoamines:
- Acetylcholine: This is a different type of neurotransmitter involved in muscle activation and various brain functions.
- GABA (gamma-aminobutyric acid): This is the main inhibitory neurotransmitter in the central nervous system.
- Glutamate: This is the main excitatory neurotransmitter in the central nervous system.
- Glycine: An inhibitory neurotransmitter in the central nervous system.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 46
Incorrect
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The predominant site in the lymph node where T lymphocytes are found is:
Your Answer: Cortex
Correct Answer: Paracortex
Explanation:Paracortex is found between the cortex and the medulla and it is composed of a non-nodular type of arrangement that is mostly made up of T cells.
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This question is part of the following fields:
- Immunology
- Medicine
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Question 47
Correct
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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 48
Incorrect
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Endotoxin will typically act on which one of the following cells, to produce endogenous pyrogens?
Your Answer: B lymphocytes
Correct Answer: Monocytes
Explanation:Endotoxin, also known as lipopolysaccharides or lipoglycans, are molecules that consist of a lipid and a polysaccharide. They bind to many cell types, but especially to monocytes, promoting the secretion of proinflammatory cytokines, acting as a pyrogen.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 49
Correct
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What is the main reason for checking the urea and electrolytes prior to commencing a patient on amiodarone?
Your Answer: To detect hypokalaemia
Explanation:All antiarrhythmic drugs have the potential to cause arrhythmias. Coexistent hypokalaemia significantly increases this risk.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 50
Incorrect
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The coronary arteries fill during?
Your Answer: Systole
Correct Answer: Diastole
Explanation:During systole the coronary arteries collapse as a result of the pressure due to 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 subendocardium.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 51
Incorrect
-
The following occurs as a result of 2,3 Bisphosphoglycerate binding to deoxyhaemoglobin
Your Answer: No change to deoxyhaemoglobin's affinity for oxygen
Correct Answer: A reduction in deoxyhaemoglobin's affinity for oxygen
Explanation:2,3-BPG acts as a heteroallosteric effector of haemoglobin, lowering haemoglobin’s affinity for oxygen by binding preferentially to deoxyhaemoglobin. An increased concentration of BPG in red blood cells favours formation of the T, low-affinity state of haemoglobin and so the oxygen-binding curve will shift to the right.
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This question is part of the following fields:
- Haematology
- Medicine
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Question 52
Incorrect
-
The main breakdown of fatty acids (by B-oxidation) occurs in which part of the cell?
Your Answer: Cytoplasm
Correct Answer: Mitochondria
Explanation:Once inside the mitochondria, the β-oxidation of fatty acids occurs via five recurring steps:Activation by ATPOxidation by FAD,Hydration,Oxidation by NAD+,Thiolysis,The final product is acetyl-CoA, the entry molecule for the citric acid cycle.
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This question is part of the following fields:
- Medicine
- Metabolism
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Question 53
Incorrect
-
What is the most appropriate management of a DVT during pregnancy?
Your Answer: Aspirin
Correct Answer: Heparin
Explanation:Low molecular weight heparin (LMWH) is safe in pregnancy and is therefore the first line management. Warfarin is teratogenic and must be avoided whilst the other options have no role to play.
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This question is part of the following fields:
- Medicine
- Respiratory
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Question 54
Incorrect
-
Preload:
Your Answer: Is the tension at which the load is lifted
Correct Answer: Is the degree to which the myocardium is stretched before is contracts
Explanation:Preload is end diastolic volume. It is the degree to which the heart muscle fiber is stretched when it fills up completely just before the heart contracts.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 55
Incorrect
-
An elderly man presents with fever of 38°C and a very severe headache. His BP is 85/50 mm Hg. He has neck stiffness and photophobia. What is the most appropriate management?
Your Answer: Intravenous fluid
Correct Answer: CT head
Explanation:In elderly patients, symptoms suggestive of meningitis could be due to an intracranial mass lesion (such as abscess, tumour or an intracerebral haematoma). Therefore elderly patients are increased risk of cerebral herniation from an LP. A CT head should be done before an LP to exclude a mass lesion.
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This question is part of the following fields:
- Geriatrics
- Medicine
-
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Question 56
Incorrect
-
When one of the two copies of the autosomes has a mutation and the protein produced by the normal form of the gene cannot compensate. The affected individual has an:
Your Answer: X-linked dominant disorder
Correct Answer: Autosomal dominant disorder
Explanation:An autosomal dominant trait will be expressed no matter the consequence. If one chromosome has a mutation the other will not be able to compensate for the mutation hence the protein formed will be mutated and will not function properly.
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This question is part of the following fields:
- Genetics
- Medicine
-
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Question 57
Incorrect
-
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 58
Correct
-
Which immunological cells are predominant in the lymph node (almost 98 % residence)?
Your Answer: Lymphocytes
Explanation:Lymph nodes are a lymphoid organ mostly consisting of lymphocytes: B cells in the cortex from where they mature and proliferate and T cells in the paracortex. The medulla is also composed of lymphocytes and macrophages.
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This question is part of the following fields:
- Immunology
- Medicine
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Question 59
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: Omega-3 fatty acid
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)
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This question is part of the following fields:
- Medicine
- Pharmacology
-
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Question 60
Incorrect
-
Select the correct pairing regarding the surface of the cerebral hemispheres.
Your Answer: None of the above
Correct 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 61
Correct
-
Which of the following drugs requires plasma level monitoring?
Your Answer: Vancomycin
Explanation:All patients require plasma-vancomycin measurement (after 3 or 4 doses if renal function normal, earlier if renal impairment). There is a risk of nephrotoxicity including renal failure, interstitial nephritis and ototoxicity.
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This question is part of the following fields:
- Medicine
- Pharmacology
-
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Question 62
Correct
-
Calcium needed for cardiac muscle contraction is made available during which phase of the action potential?
Your Answer: 2
Explanation:It is made available during the plateau phase of the action potential i.e. phase 2. During the plateau phase of the action potential, Calcium from the extracellular fluid enters through the L type of calcium channels. This entry triggers the release of more calcium from the sarcoplasmic reticulum via the ryanodine receptors.
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This question is part of the following fields:
- Cardiovascular
- Medicine
-
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Question 63
Incorrect
-
The thalamus is a large collection of neuronal groups within the diencephalons which participates in:
Your Answer: Limbic functions only
Correct Answer: Sensory, motor and limbic
Explanation:The thalamus has multiple functions. It is the relay station for every sensory system (except olfactory, regulates the sleep-wake cycle and consciousness and also relays motor information.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 64
Incorrect
-
A 25-year-old female presents to the emergency department with severe breathlessness and tinnitus. She is under treatment for asthma and depression with albuterol and amitriptyline respectively.On examination, she seems agitated with a BP of 100/44, a pulse rate of 112 bpm, a respiratory rate of 30 cycles/min, and a temperature of 37.8'C.An arterial blood gas performed reveals:pH: 7.48 (7.36 – 7.44)pO2: 11.2 kPa (11.3 – 12.6 kPa)pCO2: 1.9 kPa (4.7 – 6.0 kPa)Bicarbonate: 13 mmol/l (20 – 28 mmol/L)What is the most probable diagnosis?
Your Answer: Acute asthma exacerbation
Correct Answer: Salicylate poisoning
Explanation:The blood gas analysis provided above is suggestive of a mixed respiratory alkalosis and metabolic acidosis characteristic of salicylate overdose.Pathophysiology:The direct stimulation of the cerebral medulla causes hyperventilation and respiratory alkalosis.As it is metabolized, it causes an uncoupling of oxidative phosphorylation in the mitochondria. Lactate levels then increase due to the increase in anaerobic metabolism. This, along with a slight contribution from the salicylate metabolites result in metabolic acidosis.Tinnitus is characteristic and salicylate ototoxicity may produce deafness. Other neurological sequelae include encephalopathy and agitation, seizures and CNS depression and coma. Cardiovascular complications include tachycardia, hypotension, and dysrhythmias (VT, VF, and asystole).
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This question is part of the following fields:
- Medicine
- Pharmacology
-
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Question 65
Incorrect
-
According to Starling's law of the heart:
Your Answer: Cardiac output is not affected by change in venous return
Correct 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 66
Correct
-
The febrile response to PGE2 will be impaired with the knockout of which one of the following prostaglandin receptors?
Your Answer: Ep3
Explanation:Prostaglandin EP3 receptor is a receptor for prostaglandin E2. Fever occurs as a result of the action of prostaglandin E2 and requires EP3 receptors in the preoptic area. Therefore, if there is an absence of EP3 receptors, fever caused by prostaglandin E2 will not occur.
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This question is part of the following fields:
- Endocrinology
- Medicine
-
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Question 67
Incorrect
-
A 78-year-old male with long-standing Alzheimer's disease is being reviewed in your clinic. Which among the following is true regarding memantine, a drug which has been approved for the management of dementia?
Your Answer: Amantadine can increase its unwanted effects
Correct Answer: It is an NMDA-receptor antagonist
Explanation:Memantine is an antagonist of the NMDA (N-Methyl-D-Aspartate)-receptor subtype of glutamate receptor. It is used to slow the neurotoxicity thought to be involved in Alzheimer’s disease and other neurodegenerative diseases.
Drug interactions:
- When given concomitantly with other NMDA-receptor antagonists (e.g., ketamine, amantadine) there is increased risk of psychosis.
- Dopamine agonists, L-dopa, and anticholinergics enhance effects of memantine.
- Antispasmodics (e.g., baclofen) enhance effects, as memantine has some antispasmodic effects.
- Drugs excreted by cationic transporters in the kidney (e.g. quinine, cimetidine, ranitidine) reduce excretion.
- Common adverse effects include dizziness, headache, confusion, diarrhoea, and constipation.
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This question is part of the following fields:
- Medicine
- Pharmacology
-
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Question 68
Incorrect
-
Which of the following does not contribute to increased stroke volume during exercise?
Your Answer: Increased sympathetic stimulation of ventricular muscle
Correct Answer: Increased length of filling time during diastole
Explanation:Prolonged aerobic exercise training may also increase stroke volume, which frequently results in a lower (resting) heart rate. Reduced heart rate prolongs ventricular diastole (filling), increasing end-diastolic volume, and ultimately allowing more blood to be ejected.
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This question is part of the following fields:
- Cardiovascular
- Medicine
-
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Question 69
Correct
-
Alveolar epithelial cells:
Your Answer: Type 2 represent 60% of the cells
Explanation:Type I alveolar cells are squamous (giving more surface area to each cell) and cover approximately 90–95% of the alveolar surface. Type I cells are involved in the process of gas exchange between the alveoli and blood. Type II alveolar cells cover a small fraction of the alveolar surface area. Their function is of major importance in the secretion of pulmonary surfactant, which decreases the surface tension within the alveoli. They are also capable of cellular division, giving rise to more type I alveolar cells when the lung tissue is damaged. These cells are granular and roughly cuboidal. Type II alveolar cells are typically found at the blood-air barrier. Although they only comprise <5% of the alveolar surface, they are relatively numerous (60% of alveolar epithelial cells).
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This question is part of the following fields:
- Medicine
- Respiratory
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Question 70
Incorrect
-
Visual pathways - Choose the true statement:
Your Answer: The parvocellular pathway carries signals for detection of movement
Correct Answer: The lateral geniculate nucleus, magnocellular & parvocellular pathways project to the primary visual cortex
Explanation:The optic chiasm is made by the decussation of optic fibers on the nasal side. The magnocellular pathway carries signals for detection of movement. The parvocellular pathway carries cells for detection of shape, size, colour and clarity. The lateral geniculate nucleus (LGN) is the relay centre in the thalamus for he visual pathway. It has layers of magnocellular cells and parvocellular cells that are interleaved with layers of koniocellular cells. The LGN is the main central connection for the optic nerve to the occipital lobe, particularly the primary visual cortex.
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This question is part of the following fields:
- Medicine
- Neurology
-
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Question 71
Incorrect
-
Which receptor type is associated with the inhibition of pancreatic endocrine secretion?
Your Answer: Α1
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 72
Correct
-
Question 73
Correct
-
What is the structure of nucleosomes?
Your Answer: Strands of double strand DNA + histones
Explanation:DNA is packed and condensed by binding to histone proteins. The double stranded DNA forms a complex with histone proteins which is called a nucleosome. There are 8 histone proteins contained in one core of nucleosome.
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This question is part of the following fields:
- Genetics
- Medicine
-
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Question 74
Incorrect
-
Which of the following structures of the cardiac conduction system is located in the right posterior portion of the interatrial septum?
Your Answer: Purkinje system
Correct Answer: AV node
Explanation:AV node is located at the right posterior portion of the interatrial septum.
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This question is part of the following fields:
- Cardiovascular
- Medicine
-
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Question 75
Correct
-
The sympathetic supply to the stomach comes from the:
Your Answer: Celiac plexus
Explanation:The vagus nerve supplies the stomach and up to proximal two-thirds of the large intestine and has parasympathetic stimulation. The sympathetic chain which begins at the level of he 1st thoracic vertebra and extends up to 3rd lumbar vertebra gives off the celiac plexus which mainly supplies the stomach. The mesenteric plexus mainly supplies the small intestine and is located below the celiac plexus in the sympathetic chain.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
-
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Question 76
Incorrect
-
Regarding restriction fragment length polymorphisms (RFLP) and Gene Knockout Mouse Models. All are true except:
Your Answer: Knockout models are important in studying roles of sequenced genes with unknown function
Correct Answer: In knockout mouse models a gene is turned on through targeted mutation
Explanation:In RFLP, polymorphism occurs in 98% of the non coding genome, resulting in no phenotypical change in the organism. A gene is not turned on by a mutation, rather the mutation at the restriction site will alter the DNA and the DNA will now form fragments of different lengths. PCR is a better technique than RFLP.
A knockout, as related to genomics, refers to the use of genetic engineering to inactivate or remove one or more specific genes from an organism. Scientists create knockout organisms to study the impact of removing a gene from an organism, which often allows them to then learn something about that gene’s function.
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This question is part of the following fields:
- Genetics
- Medicine
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Question 77
Incorrect
-
All of the following features may suggest malignant changes in a melanocytic naevi, EXCEPT?
Your Answer: Itch
Correct Answer: Decrease in size
Explanation:Melanocytic naevi are skin tumours produced by melanocytes. They usually present in childhood but increase during puberty. The mnemonic A-B-C-D, is used by institutions to assess for suspicion of malignancy. The letters stand for asymmetry, border, colour, and diameter. If a mole starts changing in size, colour, shape or, especially, if the border of a mole develops ragged edges or becomes larger than a pencil eraser, it would be an appropriate time to consult with a physician. Other warning signs include if it begins to crust over, bleed, itch, or become inflamed.
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This question is part of the following fields:
- Dermatology
- Medicine
-
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Question 78
Incorrect
-
The midbrain, medulla and pons, contain the following cranial nerve nuclei?
Your Answer: CN 6 – 12
Correct Answer: CN 3 - 12
Explanation:The cranial nerves (with the exception of I and II) originate in the brainstem, which includes the midbrain, the pons, and the medulla.
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This question is part of the following fields:
- Medicine
- Neurology
-
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Question 79
Incorrect
-
Telomerase is active in all of the following cells, except:
Your Answer: Certain osteoblasts
Correct Answer: Certain liver cells
Explanation:Telomerase is an enzyme that adds repetitive nucleotide sequences to the ends of chromosomes (telomeres), preventing their shortening during cell division. Telomerase activity is crucial for cells that divide frequently and need to maintain their telomere length for continued proliferation. These include:
- Stem cells: They have high telomerase activity to maintain their long-term proliferative capacity.
- Germ cells: These cells also have active telomerase to ensure the stability of genetic material across generations.
- Certain white blood cells: Some immune cells, particularly those that need to proliferate in response to infection, show telomerase activity.
- Certain cancer cells: Many cancer cells reactivate telomerase, which contributes to their uncontrolled growth and immortality.
However, most somatic cells, including certain liver cells, do not exhibit significant telomerase activity. While some liver cells might show low levels of telomerase activity during regeneration, it is not generally active in normal, differentiated liver cells.
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This question is part of the following fields:
- Genetics
- Medicine
-
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Question 80
Incorrect
-
Where is Vitamin B12 mainly stored in the body?
Your Answer: Distal ileum
Correct Answer: Liver
Explanation:The total amount of vitamin B12 stored in body is about 2–5 mg in adults. Around 50% of this is stored in the liver. Approximately 0.1% of this is lost per day by secretions into the gut, as not all these secretions are reabsorbed.
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This question is part of the following fields:
- Haematology
- Medicine
-
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Question 81
Incorrect
-
The hyperpolarization phase of pacemaker cells is dominated by ____ current.
Your Answer: PO4-
Correct 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 82
Incorrect
-
Which of the following happens when anterograde neurons are stimulated?
Your Answer:
Correct Answer: Smooth muscle relaxation ahead of the stimulus
Explanation:Nitric oxide is thought to act as an anterograde neurotransmitter. Nitric oxide causes relaxation of smooth muscles ahead of the stimulus. Clinically it is used as a potent vasodilator.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
-
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Question 83
Incorrect
-
The collection of genes that are termed the major histocompatibility complex (MHC) are found on:
Your Answer:
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
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This question is part of the following fields:
- Immunology
- Medicine
-
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Question 84
Incorrect
-
The branche(s) of the left coronary artery include:
Your Answer:
Correct Answer: Left circumflex artery & anterior interventricular artery
Explanation:The left main coronary divides into branches:
1. The left anterior descending artery branches off the left coronary artery and supplies blood to the front of the left side of the heart.
2. The circumflex artery branches off the left coronary artery and encircles the heart muscle.
The anterior interventricular artery is otherwise known as the anterior descending branch. The posterior descending artery comes from Right coronary artery.
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This question is part of the following fields:
- Cardiovascular
- Medicine
-
-
Question 85
Incorrect
-
All of the following are associated with yellow nail syndrome except:
Your Answer:
Correct Answer: Cardiomegaly
Explanation:Yellow nail syndrome is a very rare medical syndrome that includes pleural effusions, lymphedema (due to under development of the lymphatic vessels) and yellow dystrophic nails. Approximately 40% will also have bronchiectasis. It is also associated with chronic sinusitis and persistent coughing and it usually affects adults.
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This question is part of the following fields:
- Dermatology
- Medicine
-
-
Question 86
Incorrect
-
Which of the following with regard to autosomal dominant disorders are true:
Your Answer:
Correct Answer: The offspring of a heterozygous individual has a 50% chance of inheriting the chromosome carrying the disease allele
Explanation:50% of the children will be effected from parents who are heterozygous for an autosomal dominant disorder. An allele can be dominant or recessive. Individuals, meanwhile, can be homozygous or heterozygous: individuals who are homozygous for a certain gene carry two copies of the same allele. individuals who are heterozygous for a certain gene carry two different alleles.
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This question is part of the following fields:
- Genetics
- Medicine
-
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Question 87
Incorrect
-
During bone growth-the epiphysis are separated from the diaphysis by actively proliferating cartilage known as:
Your Answer:
Correct Answer: Epiphysial plate
Explanation:The epiphysial plate, physis, or growth plate, is a hyaline cartilage plate located near the ends of long bones; it consists of growing tissue. It is found in children and teenagers; in adults, it is replaced by an epiphysial line or epiphysial closure. The epiphysial plate is divided into zones: zone of reserve, proliferation, maturation and hypertrophy, calcification, and ossification.
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This question is part of the following fields:
- Endocrinology
- Medicine
-
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Question 88
Incorrect
-
The extrinsic coagulation pathway is initiated by activation of which clotting factor?
Your Answer:
Correct Answer: Factor VII
Explanation:The tissue factor pathway (extrinsic) begins following damage to the blood vessel. FVII leaves the circulation and comes into contact with tissue factor (TF) expressed on tissue-factor-bearing cells (stromal fibroblasts and leukocytes), forming an activated complex (TF-FVIIa).
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This question is part of the following fields:
- Haematology
- Medicine
-
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Question 89
Incorrect
-
What causes increased insulin sensitivity?
Your Answer:
Correct Answer: Exercise
Explanation:Physical activity, through its effect on insulin sensitivity, is one of the main modifiable risk factors for type 2 diabetes. It is estimated that by each weekly 500 kcal increment in exercise related energy consumption, the lifetime risk of suffering from type 2 diabetes is reduced by 9%. Up to two hours after exercise, glucose uptake is elevated due to insulin independent mechanisms; however, insulin sensitivity remains increased for at least 16 hours after exercising.
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This question is part of the following fields:
- Endocrinology
- Medicine
-
-
Question 90
Incorrect
-
Which of the following takes place during fasting
Your Answer:
Correct Answer: Migrating motor complex
Explanation:Migrating motor complexes (MMC) are waves of electrical activity that sweep through the intestines in a regular cycle during fasting. These motor complexes trigger peristaltic waves, which facilitate transportation of indigestible substances such as bone, fiber, and foreign bodies from the stomach, through the small intestine, past the ileocecal sphincter, and into the colon.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
-
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Question 91
Incorrect
-
Question 92
Incorrect
-
The process of DNA amplification and quantification is called:
Your Answer:
Correct Answer: PCR
Explanation:PCR/polymerase chain reaction is a procedure carried out in a test tube that can be used on the smallest amount of DNA to amplify it, allowing for millions of copies of specific nucleotides to be made.
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This question is part of the following fields:
- Genetics
- Medicine
-
-
Question 93
Incorrect
-
What is the most abundant cell type in the central nervous system called?
Your Answer:
Correct Answer: Astrocyte
Explanation:Astrocytes are the supporting cells of the central nervous system. There are two types; the fibrous type is found in the white matter and the protoplasmic type in the grey matter. They are the most abundant cell type in the CNS.
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This question is part of the following fields:
- Medicine
- Neurology
-
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Question 94
Incorrect
-
Vasodilatation of coronary arteries is caused by:
Your Answer:
Correct Answer: Hypoxia
Explanation:The heart is highly metabolically active and boasts the highest oxygen consumption by mass of any organ. This demand for oxygen is met by the coronary circulation, which is responsible for delivering blood to the myocardium and represents approximately 5% of cardiac output. Vasodilation may be due to the local effect of hypoxia on coronary vessels, or local metabolic vasodilation, or the activation of β-adrenoceptors or some combination of these mechanisms.
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This question is part of the following fields:
- Cardiovascular
- Medicine
-
-
Question 95
Incorrect
-
Which of the following is NOT a component of bile?
Your Answer:
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 96
Incorrect
-
The channel that coalesces the small pancreatic duct radicles before joining the common bile duct is known as the:
Your Answer:
Correct Answer: Duct of Wirsung
Explanation:The small ducts from the pancreas coalesce into a single duct known as the pancreatic duct or the duct of Wirsung. It usually joins the bile duct at the ampulla of Vater before entering the duodenum.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
-
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Question 97
Incorrect
-
Which of the following derivatives of proopiomelanocortin is an opioid peptide?
Your Answer:
Correct Answer: ß-endorphin
Explanation:ß-endorphin is an endogenous opioid neuropeptide which is mainly synthesized and stored in the anterior pituitary gland, derived from the precursor proopiomelanocortin (POMC). Some studies have shown that immune system cells are also capable of synthesizing ß-endorphin. β-endorphin is thought to exert a tonic inhibitory influence upon GNRH secretion and to be an important regulator of reproductive function.
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This question is part of the following fields:
- Endocrinology
- Medicine
-
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Question 98
Incorrect
-
Amongst the following cells, which is responsible for the secretion of defensins?
Your Answer:
Correct 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.
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This question is part of the following fields:
- Immunology
- Medicine
-
-
Question 99
Incorrect
-
Regarding taste threshold and intensity discrimination:
Your Answer:
Correct Answer: 30% change in concentration of substance tasted is necessary before an intensity difference can be detected
Explanation:The ability of humans to differentiate differences in intensity of taste is poor. A 30% change in the concentration of the substance being tasted is required before an intensity difference is perceived.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 100
Incorrect
-
The Afferent neuron that supplies all sensory elements of the muscle spindle is what type of sensory neuron?
Your Answer:
Correct Answer: Ia
Explanation:Muscle spindle is supplied by both sensory and motor nerves. Sensory supply is Type Ia fibers whereas motor supply is gamma motor neurone.
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This question is part of the following fields:
- Medicine
- Neurology
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SESSION STATS - PERFORMANCE PER SPECIALTY
