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  • Question 1 - Glucose absorption in the small intestine is coupled with which of the following...

    Correct

    • 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.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      8.4
      Seconds
  • Question 2 - A 36 year old man arrives at the clinic complaining of pain and...

    Incorrect

    • A 36 year old man arrives at the clinic complaining of pain and swelling of the left knee, ankles and right hallux. He has acute conjunctivitis, and dysuria. He suffered from an episode of gastroenteritis two weeks back. Clinical examination shows left Achilles tendonitis and right plantar fasciitis. Radiological examination reveals left sacroiliitis, with evidence of enthesitis, joint erosions and periostitis. HLA-B27 is positive. Which of the following is the most likely diagnosis?

      Your Answer: Ankylosing spondylitis

      Correct Answer: Reiter’s syndrome

      Explanation:

      Reactive arthritis, (formerly known as Reiter’s syndrome), is an autoimmune condition that occurs after a bacterial infection of the gastrointestinal or urinary tract. It is categorized as a seronegative spondylarthritis because of its association with HLA-B27. Reactive arthritis primarily affects young men and usually presents with musculoskeletal or extra‑articular symptoms. The characteristic triad consists of arthritis, conjunctivitis, and urethritis. The diagnosis is based on clinical features such as patient history and physical examination; there are no specific tests for reactive arthritis. Treatment is primarily symptomatic and consists of the administration of NSAIDs, as most patients recover spontaneously. extraarticular dermatologic manifestations include skin lesions of the glans resembling psoriasis (balanitis circinata); hyperkeratinisation of the palms and soles (keratoderma blenorrhagicum), oral ulcers.

    • This question is part of the following fields:

      • Connective Tissue
      • Medicine
      16.4
      Seconds
  • Question 3 - With regards to splenic micro-architecture which is not contained within the red pulp...

    Correct

    • With regards to splenic micro-architecture which is not contained within the red pulp

      Your Answer: Malpighian corpuscles

      Explanation:

      Red pulp is responsible for mechanical filtration of red blood cells and is composed of sinusoids, which are filled with blood, splenic cords of reticular fibers and a marginal zone bordering on white pulp. White pulp provides an active immune response through humoral and cell-mediated pathways. Composed of nodules, called Malpighian corpuscles. These are composed of: lymphoid follicles, rich in B-lymphocytes and periarteriolar lymphoid sheaths (PALS), rich in T-lymphocytes.

    • This question is part of the following fields:

      • Haematology
      • Medicine
      238
      Seconds
  • Question 4 - Which of the following happens when anterograde neurons are stimulated? ...

    Incorrect

    • Which of the following happens when anterograde neurons are stimulated?

      Your Answer: Smooth muscle contraction ahead of the stimulus

      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.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      6.2
      Seconds
  • Question 5 - Which of the following features do mast cells and basophils have in common:...

    Correct

    • Which of the following features do mast cells and basophils have in common:

      Your Answer: Are essential for immediate type-hypersensitivity reactions

      Explanation:

      Anaphylaxis is a severe immediate allergic reaction of rapid onset affecting many body systems. It is due to the release of inflammatory mediators and cytokines from mast cells and basophils. Basophils are the least common of the granulocytes, representing about 0.5 to 1% of circulating white blood cells. However, they are the largest type of granulocyte. They are responsible for inflammatory reactions during immune response, as well as in the formation of acute and chronic allergic diseases, including anaphylaxis, asthma, atopic dermatitis and hay fever. They can perform phagocytosis (cell eating), produce histamine and serotonin that induce inflammation, and heparin that prevents blood clotting. Mast cells are similar in appearance and function. Both cell types store histamine, a chemical that is secreted by the cells when stimulated.

    • This question is part of the following fields:

      • Immunology
      • Medicine
      21.4
      Seconds
  • Question 6 - A 75 year old man presented to hospital after suffering a stroke. The...

    Correct

    • A 75 year old man presented to hospital after suffering a stroke. The doctor admitted him and advised of the Barthel score index. During rehabilitation, which one of the following limitations are best described by Barthel score index?

      Your Answer: Floor and ceiling effects

      Explanation:

      Barthel scoring has floor and ceiling effects which is the most widely recognised limitation. Floor effect means that the patient who is bed bound can score initially low, whereas the ceiling effect shows that despite being bed bound, a patient can achieve a maximum score i.e. 100. The test is easy to perform and correlates well with other prognostic scales.

    • This question is part of the following fields:

      • Geriatrics
      • Medicine
      172.3
      Seconds
  • Question 7 - Which part of the chromosome plays a role in preserving its integrity and...

    Incorrect

    • Which part of the chromosome plays a role in preserving its integrity and stability?

      Your Answer: Centromere

      Correct Answer: Telomere

      Explanation:

      Telomeres are non coding DNA plus proteins that are found at the end of the linear chromosomes. They maintain the integrity of the chromosomes and prevent their shortening

    • This question is part of the following fields:

      • Genetics
      • Medicine
      9.4
      Seconds
  • Question 8 - Where is the most erythropoietin produced? ...

    Correct

    • Where is the most erythropoietin produced?

      Your Answer: Kidneys

      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.

    • This question is part of the following fields:

      • Haematology
      • Medicine
      3.5
      Seconds
  • Question 9 - Wernicke’s area: ...

    Correct

    • Wernicke’s area:

      Your Answer: Is concerned with comprehension of auditory and visual information

      Explanation:

      Wernicke’s area is located in the categorical hemisphere or left hemisphere in about 95% of right handed individuals and 60% of left handed individuals. It is involved in the comprehension or understanding of written and spoken language. In contrast Broca’s area is involved in production of language.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      5.9
      Seconds
  • Question 10 - The main efferent input of the posterior pituitary gland comes from: ...

    Correct

    • 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.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      13.6
      Seconds
  • Question 11 - A 30-year-old male with a history of premature cardiovascular disease in the family...

    Correct

    • A 30-year-old male with a history of premature cardiovascular disease in the family has come for review of his lab investigations. His fasting cholesterol is 8.4 mmol/l with high-density lipoprotein (HDL) of 1.6 mmol/l. You elect to commence him on atorvastatin 20 mg PO daily.Which of the following best describes the mechanism of action of the statins?

      Your Answer: They inhibit HMG CoA reductase

      Explanation:

      Statins are a selective, competitive inhibitor of hydroxymethylglutaryl-CoA (HMG-CoA) reductase, which is the enzyme responsible for the conversion of HMG-CoA to mevalonate in the cholesterol synthesis pathway.Statins are usually well tolerated with myopathy, rhabdomyolysis, hepatotoxicity, and diabetes mellitus being the most common adverse reactions. This is the rate-limiting step in cholesterol synthesis, that leads to increased hepatic low-density lipoprotein (LDL) receptors and reduced hepatic VLDL synthesis coupled with increased very-low-density lipoprotein (VLDL) clearance.

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      15.7
      Seconds
  • Question 12 - A 60-year-old male is under treatment with azathioprine after a renal transplant. During...

    Correct

    • A 60-year-old male is under treatment with azathioprine after a renal transplant. During his review, he complains of pain and swelling over his left great toe. Investigations reveal hyperuricemia. Suspecting gout, he was started on allopurinol. Subsequently, he develops aplastic anaemia. Which of the following is the most appropriate reason for his bone marrow failure?

      Your Answer: Mercaptopurine toxicity

      Explanation:

      The cause for bone marrow suppression in this patient is most probably mercaptopurine toxicity.Azathioprine is metabolized to 6-mercaptopurine (6-MP), which itself is metabolized by xanthine oxidase. Xanthine oxidase inhibition by allopurinol leads to the accumulation of 6-MP which then precipitates bone marrow failure. This may be potentially fatal if unrecognized.Clinical presentation:Toxicity symptoms include gastrointestinal symptoms, bradycardia, hepatotoxicity, myelosuppression.

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      11.9
      Seconds
  • Question 13 - The layers of the neocortex from the 1st to the 6th are arranged...

    Incorrect

    • The layers of the neocortex from the 1st to the 6th are arranged as follows:

      Your Answer: Multiform, external granular, external pyramidal, internal granular, internal pyramidal, molecular

      Correct Answer: Molecular, external granular, external pyramidal, internal granular, internal pyramidal, multiform

      Explanation:

      The layers of neocortex from outermost to innermost include: the molecular, external granular layer, external pyramidal, internal granular, internal pyramidal and multiform layer.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      38.5
      Seconds
  • Question 14 - The neurotransmitter utilised by the Purkinje cells is: ...

    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.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      6.6
      Seconds
  • Question 15 - Which of the following is NOT associated with the development of aortic regurgitation?...

    Correct

    • Which of the following is NOT associated with the development of aortic regurgitation?

      Your Answer: Dilated cardiomyopathy

      Explanation:

      Aortic insufficiency, is often due to the aortic root dilation, which is idiopathic in over 80% of cases, but otherwise may result from aging, syphilitic aortitis, osteogenesis imperfecta, aortic dissection, Bechet’s disease, reactive arthritis and systemic hypertension. Additionally, aortic insufficiency has been linked to the use of some medications and other potential causes that affect the valve directly including Marfan’s syndrome, Ehlers–Danlos syndrome, ankylosing spondylitis, and systemic lupus erythematosus. In acute cases of aortic insufficiency, the main causes are infective endocarditis, aortic dissection or trauma. Dilated cardiomyopathy is associated with the development of mitral regurgitation, not aortic regurgitation

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      8.9
      Seconds
  • Question 16 - Endotoxin ...

    Correct

    • Endotoxin

      Your Answer: Composed of Lipid A in liposaccharide in cell wall

      Explanation:

      Lipopolysaccharides (LPS), also known as lipoglycans and endotoxins, are large molecules consisting of a lipid (lipid A) and a polysaccharide composed of O-antigen, outer core and inner core joined by a covalent bond; they are found in the outer membrane of Gram-negative bacteria, and elicit strong immune responses in animals.

    • This question is part of the following fields:

      • Infectious Diseases
      • Medicine
      9.4
      Seconds
  • Question 17 - Regarding oxidative deamination of amino acids, which of the following is true? ...

    Incorrect

    • Regarding oxidative deamination of amino acids, which of the following is true?

      Your Answer: Leads to the formation of aspartate

      Correct Answer: Occurs in the kidney & liver

      Explanation:

      Oxidative deamination is a form of deamination that generates α-keto acids and other oxidized products from amine-containing compounds, and occurs largely in the liver and kidney. Oxidative deamination is an important step in the catabolism of amino acids, generating a more metabolizable form of the amino acid, and also generating ammonia as a toxic by-product. The addition of ubiquitin to a substrate protein is called ubiquitination.

    • This question is part of the following fields:

      • Cell Biology
      • Medicine
      10.1
      Seconds
  • Question 18 - As assessed by immunocytochemistry and electron microscopy, the anterior pituitary gland contains how...

    Incorrect

    • As assessed by immunocytochemistry and electron microscopy, the anterior pituitary gland contains how many different types of cells?

      Your Answer: 3

      Correct Answer: 5

      Explanation:

      The pituitary is divided into three sections

      -the anterior lobe which constitute the majority of the pituitary mass and is composed primarily of five hormone-producing cell types (thyrotropes, lactotropes, corticotropes, somatotropes and gonadotropes) each secreting thyrotropin, prolactin, ACTH, growth hormone and gonadotropins (FSH and LH) respectively.

      There is also a sixth cell type in the anterior lobe -the non-endocrine, agranular, folliculostellate cells.

      The intermediate lobe produces melanocyte-stimulating hormone and endorphins, whereas the posterior lobe secretes anti-diuretic hormone (vasopressin) and oxytocin.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      12
      Seconds
  • Question 19 - Telomerase is active in the following cells except: ...

    Correct

    • Telomerase is active in the following cells except:

      Your Answer: Certain osteoblasts

      Explanation:

      Some cells have the ability to reverse telomere shortening by expressing telomerase, an enzyme that extends the telomeres of chromosomes. Telomerase is an RNA-dependent DNA polymerase, meaning an enzyme that can make DNA using RNA as a template.

      Telomerase is not usually active in most somatic cells (cells of the body), but it’s active in germ cells (the cells that make sperm and eggs) and some adult stem cells. These are cell types that need to undergo many divisions, or, in the case of germ cells, give rise to a new organism with its telomeric “clock” reset.
      Interestingly, many cancer cells have shortened telomeres, and telomerase is active in these cells. If telomerase could be inhibited by drugs as part of cancer therapy, their excess division (and thus, the growth of the cancerous tumor) could potentially be stopped.
       A subset of liver cells with high levels of telomerase renews the organ during normal cell turnover and after injury.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      4.8
      Seconds
  • Question 20 - A deficiency in Cyanocobalamin leads to which clinical deficiency syndrome? ...

    Correct

    • A deficiency in Cyanocobalamin leads to which clinical deficiency syndrome?

      Your Answer: Pernicious anaemia

      Explanation:

      The main syndrome of vitamin B12 deficiency is pernicious anaemia. It is characterized by a triad of symptoms:Megaloblastic anaemiaGastrointestinal symptoms &Neurological symptoms

    • This question is part of the following fields:

      • Medicine
      • Metabolism
      6.1
      Seconds
  • Question 21 - Mean intra pleural pressure at rest with inspiration can reach: ...

    Correct

    • Mean intra pleural pressure at rest with inspiration can reach:

      Your Answer: -6 mmHg

      Explanation:

      It is a negative pressure as it is lower than the atmospheric pressure. It can start from -2.5 and reach around -6 mmHg

    • This question is part of the following fields:

      • Medicine
      • Respiratory
      4.3
      Seconds
  • Question 22 - In which of the following are the enzymatic mechanisms for producing aldosterone found?...

    Incorrect

    • In which of the following are the enzymatic mechanisms for producing aldosterone found?

      Your Answer: Zona reticularis

      Correct Answer: Zona glomerulosa

      Explanation:

      The zona glomerulosa is the outermost layer of the adrenal gland. In it, aldosterone is secreted as a response to an increase in potassium levels, decreased blood flow, or renin. This secretion is regulated by the renin-angiotensin system.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      23
      Seconds
  • Question 23 - Increase Gamma motor neuron activity produces what effect on the muscle spindle sensitivity?...

    Correct

    • Increase Gamma motor neuron activity produces what effect on the muscle spindle sensitivity?

      Your Answer: Increase

      Explanation:

      The muscle spindle is supplied by both sensory and motor nerves. Sensory supply is Type Ia fibers whereas motor supply is via gamma motor neurons. These neurons also play a role in adjusting the sensitivity of muscle spindles. Increased neuron activity increases the muscle spindle sensitivity.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      9.3
      Seconds
  • Question 24 - Which of these vitamins is not found in plants? ...

    Correct

    • Which of these vitamins is not found in plants?

      Your Answer: Vitamin B12

      Explanation:

      No fungi, plants, nor animals (including humans) are capable of producing vitamin B12. Only bacteria and archaea have the enzymes needed for its synthesis. Proved food sources of B12 are animal products (meat, fish, dairy products).

    • This question is part of the following fields:

      • Haematology
      • Medicine
      7.2
      Seconds
  • Question 25 - The consensual light reflex is co-ordinated mainly in the: ...

    Correct

    • The consensual light reflex is co-ordinated mainly in the:

      Your Answer: Edinger-Westphal nucleus

      Explanation:

      The consensual light reflex occurs when an individual’s right eye is shielded and light shines into the left eye, constriction of the right pupil will occur, as well as the left. This is because the afferent signal sent through one optic nerve connects to the Edinger-Westphal nucleus, whose axons run to both the right and the left oculomotor nerves.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      8.1
      Seconds
  • Question 26 - The Cellular Theory of Ageing involves? ...

    Correct

    • The Cellular Theory of Ageing involves?

      Your Answer: Loss of telomeres

      Explanation:

      Cellular theories of aging propose that human aging is the result of cellular aging, whereby an increasing proportion of cells reach senescence, a terminal stage at which cells will cease to divide. This will limit the body’s ability to regenerate and to respond to injury or stress. Telomeres are bits of DNA on the ends of chromosomes that protect chromosomes from sticking to each other or tangling, which could cause DNA to abnormally function. As cells replicate, telomeres shorten at the end of chromosomes, and this process correlates to senescence or cellular aging.

      Other theories include:

      1. The Free Radical Theory: Implicates the gradual accumulation of oxidative cellular damage as a fundamental driver of cellular aging. This theory has evolved over time to emphasize the role of free radical induced mitochondrial DNA (mtDNA) mutations and the accumulation of mtDNA deletions. Given the proximity of mtDNA to the electron transport chain, a primary producer of free radicals, it postulates that the mutations would promote mitochondrial dysfunction and concomitantly increase free radical production in a positive feedback loop. It is known that diet, lifestyle, drugs (e.g. tobacco and alcohol) and radiation etc., are all accelerators of free radical production within the body.
      2. Error theory: based on the idea that errors can occur in the transcription of the synthesis of DNA. These errors are perpetuated and eventually lead to systems that do not function at the optimum level. The organism’s aging and death are attributable to these events (Sonneborn, 1979).
      3. The Cross-Linking Theory: also referred to as the Glycosylation Theory of Aging. In this theory it is the binding of glucose (simple sugars) to protein, (a process that occurs under the presence of oxygen) that causes various problems. Once this binding has occurred the protein becomes impaired and is unable to perform as efficiently. Living a longer life is going to lead to the increased possibility of oxygen meeting glucose and protein and known cross-linking disorders include senile cataract and the appearance of tough, leathery and yellow skin.
      4. The Neuroendocrine Theory First proposed by Professor Vladimir Dilman and Ward Dean MD, this theory elaborates on wear and tear by focusing on the neuroendocrine system. This system is a complicated network of biochemicals that govern the release of hormones which are altered by the walnut sized gland called the hypothalamus located in the brain. The hypothalamus controls various chain-reactions to instruct other organs and glands to release their hormones etc. The hypothalamus also responds to the body hormone levels as a guide to the overall hormonal activity. But as we grow older the hypothalamus loses it precision regulatory ability and the receptors which uptake individual hormones become less sensitive to them. Accordingly, as we age the secretion of many hormones declines and their effectiveness (compared unit to unit) is also reduced due to the receptors down-grading
      5. The Membrane Theory of Aging: According to this theory it is the age-related changes of the cell’s ability to transfer chemicals, heat and electrical processes that impair it. As we grow older the cell membrane becomes less lipid (less watery and more solid). This impedes its efficiency to conduct normal function and in particular there is a toxic accumulation
      6. The Decline Theory: The mitochondria are the power producing organelles found in every cell of every organ. Their primary job is to create Adenosine Triphosphate (ATP) and they do so in the various energy cycles that involve nutrients such as Acetyl-L-Carnitine, CoQ10 (Idebenone), NADH and some B vitamins etc. Enhancement and protection of the mitochondria is an essential part of preventing and slowing aging. Enhancement can be achieved with the above mention nutrients, as well as ATP supplements themselves.

    • This question is part of the following fields:

      • Cell Biology
      • Medicine
      3.1
      Seconds
  • Question 27 - A patient has been diagnosed with multi-drug resistant tuberculosis and is currently bring...

    Incorrect

    • A patient has been diagnosed with multi-drug resistant tuberculosis and is currently bring treated with rifampicin, isoniazid, and pyrazinamide. He is commenced on streptomycin.Which among the following is the most likely neurological side-effect of streptomycin?

      Your Answer: Cochlear damage

      Correct Answer: Vestibular damage

      Explanation:

      Vestibular damage is a neurological side effect of streptomycin.Streptomycin is an aminoglycoside bactericidal antibiotic. It is used in the treatment of tularaemia and resistant mycobacterial infections.The most common neurological side-effect is vestibular damage leading to vertigo and vomiting. Cochlear damage is less frequent and results in deafness. Other side-effects include rashes, angioneurotic oedema, and nephrotoxicity.

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      16.2
      Seconds
  • Question 28 - The steps of cardiac cycle in sequence are: ...

    Incorrect

    • The steps of cardiac cycle in sequence are:

      Your Answer: Isovolumic contraction, ejection, isovolumic relaxation, active ventricular filling, passive ventricular filling.

      Correct Answer: Isovolumic contraction, ejection, isovolumic relaxation, passive ventricular filling, active ventricular filling.

      Explanation:

      The cardiac cycle refers to a complete heartbeat from its generation to the beginning of the next beat, and so includes the diastole, the systole, and the intervening pause.1st stage: diastole, or passive filling is when the semilunar valves (the pulmonary valve and the aortic valve) close, the atrioventricular (AV) valves (the mitral valve and the tricuspid valve) open, and the whole heart is relaxed. 2nd stage: atrial systole, is when the atrium contracts, and blood flows from atrium to the ventricle (active filling).3rd stage: isovolumic contraction is when the ventricles begin to contract, the AV and semilunar valves close, and there is no change in volume. 4th stage: ventricular ejection, is when the ventricles are contracting and emptying, and the semilunar valves are open. 5th stage: isovolumic relaxation time, pressure decreases, no blood enters the ventricles, the ventricles stop contracting and begin to relax, and the semilunar valves close due to the pressure of blood in the aorta.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      33.1
      Seconds
  • Question 29 - The net effect of parathyroid hormone on calcium and phosphate homeostasis is? ...

    Correct

    • The net effect of parathyroid hormone on calcium and phosphate homeostasis is?

      Your Answer: Increase in Ca, decrease in phosphate

      Explanation:

      Parathyroid hormone’s main target organs are the kidneys, bone, and intestine. In the kidney, it decreases reabsorption of phosphate and increases calcium reabsorption. It also promotes absorption of calcium from bone. PTH release results in a small drop in serum phosphate concentrations.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      5.1
      Seconds
  • Question 30 - Pendrin is a Cl-/I- exchanger whose function is: ...

    Incorrect

    • Pendrin is a Cl-/I- exchanger whose function is:

      Your Answer: Uptake of iodide across the basolateral membrane into the thyrocyte

      Correct Answer: Transfer of iodide across the thyrocyte apical membrane into the colloid

      Explanation:

      Pendrin is an anion transporter present in the inner ear, thyroid and kidney. It regulates the entrance of iodide from the thyroid cell to the colloid space. It has been proposed that its role could be the maintenance of the ionic composition of the endolymph.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      12.1
      Seconds
  • Question 31 - The main source of nutrients in the liver is via the ...

    Correct

    • The main source of nutrients in the liver is via the

      Your Answer: Portal vein

      Explanation:

      The portal vein or hepatic portal vein is a blood vessel that carries blood from the gastrointestinal tract and spleen to the liver. This blood is rich in nutrients that have been extracted from food, and the liver processes these nutrients; it also filters toxins that may have been ingested with the food. 75% of total liver blood flow is through the portal vein, with the remainder coming from the hepatic artery proper.

    • This question is part of the following fields:

      • Hepatobiliary
      • Medicine
      9.8
      Seconds
  • Question 32 - Neutrophils are key components of the innate immune system. They contain numerous primary...

    Incorrect

    • 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.

    • This question is part of the following fields:

      • Immunology
      • Medicine
      20.2
      Seconds
  • Question 33 - A 25-year-old student consumed a bottle of vodka at a party, the next...

    Correct

    • A 25-year-old student consumed a bottle of vodka at a party, the next day he finds that he feels excessively thirsty and is passing more urine than usual. Which of the following mechanisms best explains the polyuria due to excessive alcohol consumption?

      Your Answer: Ethanol inhibits ADH secretion

      Explanation:

      Ethanol reduces the calcium-dependent secretion of anti-diuretic hormone (ADH) by blocking channels in the neurohypophyseal nerve terminal.Thus, ethanol’s inhibitory effect helps to explain the increased diuresis experienced during intoxicated states as well as increased free water loss; without appropriate ADH secretion, more water is excreted by the kidneys.Nausea associated with hangovers is mainly due to vagal stimulation to the vomiting centre. Following a particularly severe episode of alcohol excess, people may experience tremors due to increased glutamate production by neurons to compensate for the previous inhibition by ethanol.Management of alcoholism:Nutritional support: – Alcoholic patients should receive oral thiamine if their ‘diet may be deficient’.Pharmacological management:- Benzodiazepines for acute withdrawal- Disulfiram promotes abstinence – alcohol intake causes a severe reaction due to inhibition of acetaldehyde dehydrogenase. Patients should be aware that even small amounts of alcohol (e.g. In perfumes, foods, mouthwashes) can produce severe symptoms. Contraindications include ischaemic heart disease and psychosis.- Acamprosate reduces craving, known to be a weak antagonist of NMDA receptors, improves abstinence in placebo-controlled trials.

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      13.3
      Seconds
  • Question 34 - Which hormone secreting cell of the human anterior pituitary gland secretes growth hormone?...

    Correct

    • Which hormone secreting cell of the human anterior pituitary gland secretes growth hormone?

      Your Answer: Somatotroph

      Explanation:

      Somatotroph cells are responsible for the production of growth hormone. Somatotrophs occupy nearly 40% of the total surface area of the anterior pituitary, and they are acidophilic in nature.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      3.5
      Seconds
  • Question 35 - Which of the following foods do NOT contain high levels of folate? ...

    Incorrect

    • Which of the following foods do NOT contain high levels of folate?

      Your Answer: Yeast

      Correct Answer: Yellow vegetables

      Explanation:

      Folate naturally occurs in a wide variety of foods, including vegetables (particularly dark green leafy vegetables), fruits and fruit juices, nuts, beans, peas, dairy products, poultry and meat, eggs, seafood, grains, and some beers. Avocado, beetroot, spinach, liver, yeast, asparagus, and Brussels sprouts are among the foods with the highest levels of folate

    • This question is part of the following fields:

      • Haematology
      • Medicine
      9.3
      Seconds
  • Question 36 - Absorption of protein antigens i.e. bacterial and viral proteins takes place in the:...

    Incorrect

    • Absorption of protein antigens i.e. bacterial and viral proteins takes place in the:

      Your Answer: Mucosa-associated lymphoid tissue

      Correct Answer: Microfold cells (m cells) of the intestine

      Explanation:

      M cells are specialized epithelial cells. They have a high capacity of transcytosis of microorganisms and macromolecules. They rapidly uptake antigens and present them to immune cells associated with the gut. In contrast to absorptive enterocytes, M cells do not exert direct defence mechanisms to antigens and pathogens in the intestinal cavity. Crypts of Lieberkühn are located mainly in the small intestine and large intestine and the main function is to replenish epithelial cells and to secrete intestinal enzymatic juice as well as mucous. Brunner’s glands empty into intestinal glands and their main function is to secrete mucin and to form a protective mucus layer on the duodenal epithelial cells to protect it from acidic chyme coming from the stomach. Islets of Langerhans are located in the pancreas and secrets insulin mainly. Mucosa associated lymphoid tissue plays a role in inducing immune response after presentation of antigens.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      12.2
      Seconds
  • Question 37 - Portal vein receives its blood from all the following except: ...

    Correct

    • Portal vein receives its blood from all the following except:

      Your Answer: Kidney

      Explanation:

      The portal vein receives blood from the intestines via the superior and inferior mesenteric veins, from stomach via the gastric veins and from the spleen and pancreas via splenic vein. The kidney is supplied by the renal artery and drains into the renal vein into the inferior venacava.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      4.5
      Seconds
  • Question 38 - According to the Vaughan William's classification of antiarrhythmic agents, lidocaine is a: ...

    Incorrect

    • According to the Vaughan William's classification of antiarrhythmic agents, lidocaine is a:

      Your Answer: Class Ic agent

      Correct Answer: Class Ib agent

      Explanation:

      Lidocaine is an example of class IB antiarrhythmics.The Vaughan-Williams classification of antiarrhythmicsI: Membrane stabilizing agentsIA: Quinidine, Procainamide, DisopyramideIB: Lidocaine, MexiletineIC: Propafenone, Flecainide II: β blockers – Propranolol, EsmololIII: Agents widening AP – Amiodarone, Dronedarone, Dofetilide, Ibutilide, SotalolIV: Calcium channel blockers – Verapamil, DiltiazemV: Miscellaneous – Digoxin, adenosine, magnesium

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      16.3
      Seconds
  • Question 39 - Which enzyme deficiency causes pellagra? ...

    Incorrect

    • Which enzyme deficiency causes pellagra?

      Your Answer: Biotin

      Correct Answer: Niacin

      Explanation:

      Pellagra is a vitamin deficiency disease most frequently caused by a chronic lack of niacin (vitamin B3) in the diet.

    • This question is part of the following fields:

      • Haematology
      • Medicine
      5.5
      Seconds
  • Question 40 - A patient who has recently been diagnosed with SLE undergoes serum testing. A...

    Incorrect

    • A patient who has recently been diagnosed with SLE undergoes serum testing. A rise in which of the following antibodies would indicate severe systemic involvement?

      Your Answer: Rheumatoid factor

      Correct Answer: Anti double-stranded DNA antibodies

      Explanation:

      Anti ds-DNA antibodies are very specific for SLE and their presence most often indicates systemic spread of the disease. These antibodies are present in about 30 percent of the total cases of SLE.

    • This question is part of the following fields:

      • Connective Tissue
      • Medicine
      10.2
      Seconds
  • Question 41 - Corticospinal tracts are located in the ___ of the white matter. ...

    Incorrect

    • Corticospinal tracts are located in the ___ of the white matter.

      Your Answer: Grey matter

      Correct Answer: Anterior and lateral funiculi

      Explanation:

      The corticospinal tract is a descending or a motor tract which projects nerve fibers from the cortex of the cerebrum down to different levels of the spinal cord. The descending corticospinal tract descends from the origin, through the corona radiata, posterior half of the lateral ventricle, and enters the midbrain through the cerebral peduncle. In the medulla they form the medullary pyramids on either side of midline as lateral and anterior fibers.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      512.9
      Seconds
  • Question 42 - β-blockers are used in the treatment of angina because they have which one...

    Incorrect

    • β-blockers are used in the treatment of angina because they have which one of the following properties?

      Your Answer: Increase the left atrial volume and pressure

      Correct Answer: Decrease the heart rate and myocardial contractility

      Explanation:

      The cardiovascular effects of β-adrenoceptor block result from reduction of the sympathetic drive which includes reduced heart rate (automaticity) and reduced myocardial contractility (rate of rise of pressure in the ventricle). This will lead to reduced cardiac output and an overall fall in oxygen consumption.

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      6.3
      Seconds
  • Question 43 - Which of the following affects the magnitude of the action potential? ...

    Incorrect

    • Which of the following affects the magnitude of the action potential?

      Your Answer: The amount of intracellular Ca2+

      Correct Answer: Changes in the external Na+ concentration

      Explanation:

      The magnitude of the action potential is determined by the sodium current. Increase in external sodium will result in increased influx of sodium and hence generation of a stronger action potential.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      64.5
      Seconds
  • Question 44 - Which statement is incorrect? ...

    Incorrect

    • Which statement is incorrect?

      Your Answer: RNA polymerase creates an RNA copy of the DNA gene sequence.

      Correct Answer: Translation begins when the triplet (UGA) encoding for methionine is encountered.

      Explanation:

      Translation being when the codon for methionine is encountered which is AUG not UGA. This process is known as initiation. All the other options are correct.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      18.8
      Seconds
  • Question 45 - The function of the Golgi apparatus is ...

    Incorrect

    • The function of the Golgi apparatus is

      Your Answer: Cellular detoxification and drug metabolism

      Correct Answer: Maturation of peptides secreted by the rER into functional proteins by glycosylation

      Explanation:

      Steroidogenesis is a multi-step process that occurs in two organelles, the endoplasmic reticulum (ER) and the mitochondrion. The Golgi apparatus is a major collection and dispatch station of protein products received from the endoplasmic reticulum (ER). Proteins synthesized in the ER are packaged into vesicles, which then fuse with the Golgi apparatus. The majority of proteins synthesized in the rough ER undergo glycosylation which occurs in the Golgi apparatus. Glycosylation mainly refers in particular to the enzymatic process that attaches glycans to proteins, lipids, or other organic molecules. These cargo proteins are modified and destined for secretion via exocytosis or for use in the cell. The Golgi apparatus is also involved in lipid transport and lysosome formation.

    • This question is part of the following fields:

      • Cell Biology
      • Medicine
      11.1
      Seconds
  • Question 46 - Which of the following is NOT a pancreatic enzyme? ...

    Incorrect

    • Which of the following is NOT a pancreatic enzyme?

      Your Answer: Lipase

      Correct Answer: Pepsinogen 1

      Explanation:

      Pancreatic juice, composed of the secretions of both ductal and acinar cells, is made up of the following digestive enzymes:Trypsinogen, which is an inactive(zymogenic) protease that, once activated in the duodenum into trypsin, breaks down proteins at the basic amino acids. Trypsinogen is activated via the duodenal enzyme enterokinase into its active form trypsin.Colipase is a protein co-enzyme required for optimal enzyme activity of pancreatic lipase. It is secreted by the pancreas in an inactive form, procolipase, which is activated in the intestinal lumen by trypsin.Chymotrypsinogen, which is an inactive (zymogenic) protease that, once activated by duodenal enterokinase, breaks down proteins at their aromatic amino acids. Chymotrypsinogen can also be activated by trypsin.Carboxypeptidase, which is a protease that takes off the terminal amino acid group from a proteinSeveral elastases that degrade the protein elastin and some other proteins.Pancreatic lipase that degrades triglycerides into fatty acids and glycerol.Sterol esterasePhospholipaseSeveral nucleases that degrade nucleic acids, like DNase and RNase.Pancreatic amylase that breaks down starch and glycogen which are alpha-linked glucose polymers.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      21.9
      Seconds
  • Question 47 - The most resistant area in the brain to hypoxia is: ...

    Incorrect

    • The most resistant area in the brain to hypoxia is:

      Your Answer: Basal ganglia

      Correct Answer: Brain stem

      Explanation:

      The structures in the brainstem are more resistant to hypoxia than the cerebral cortex and the rest of the brain structures.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      2131.8
      Seconds
  • Question 48 - What is the most important determinant of ECF volume? ...

    Correct

    • What is the most important determinant of ECF volume?

      Your Answer: The amount of sodium in the ECF

      Explanation:

      The volume of the ECF is determined primarily by the total amount of osmotically active solute in the ECF. The composition of the ECF is discussed in Chapter 1. Because Na+ and Cl− are by far the most abundant osmotically active solutes in ECF, and because changes in Cl− are to a great extent secondary to changes in Na+, the amount of Na+ in the ECF is the most important determinant of ECF volume.

    • This question is part of the following fields:

      • Medicine
      • Renal
      33.1
      Seconds
  • Question 49 - Which of the following does not lower ventricular rate in atrial fibrillation? ...

    Incorrect

    • Which of the following does not lower ventricular rate in atrial fibrillation?

      Your Answer: Occulocardiac reflex

      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.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      10.9
      Seconds
  • Question 50 - Which of the following conditions is procoagulant? ...

    Incorrect

    • Which of the following conditions is procoagulant?

      Your Answer: Christmas disease

      Correct Answer: Factor V Leiden

      Explanation:

      Factor V Leiden is a genetic mutation of one of the clotting factors in the blood, Factor V. This mutation makes Factor V resistant to inactivation by activated Protein C, which normally helps to regulate clot formation. As a result, individuals with Factor V Leiden are at increased risk of developing abnormal blood clots (thrombophilia), making it a procoagulant condition.

      The other conditions listed are associated with bleeding tendencies rather than increased clotting:

      • Afibrinogenemia: A rare genetic disorder where there is a complete lack of fibrinogen, leading to bleeding problems.
      • Hemophilia: A group of inherited bleeding disorders where blood does not clot properly due to the lack of sufficient blood-clotting proteins (factors VIII or IX).
      • Hypothrombinemia: A condition characterized by low levels of prothrombin, leading to increased bleeding.
      • Christmas disease (Hemophilia B): A form of hemophilia caused by a deficiency of factor IX, resulting in a bleeding tendency.

    • This question is part of the following fields:

      • Haematology
      • Medicine
      10.3
      Seconds
  • Question 51 - The following are examples of the functions of the vascular endothelium except: ...

    Incorrect

    • The following are examples of the functions of the vascular endothelium except:

      Your Answer: Modulation of immune responses

      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.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      56.3
      Seconds
  • Question 52 - The coronary sinus, which empties into the right atrium, serves to? ...

    Correct

    • The coronary sinus, which empties into the right atrium, serves to?

      Your Answer: Drain the venous supply of the myocardium

      Explanation:

      The coronary sinus is a collection of veins joined together to form a large vessel that collects blood from the heart muscle (myocardium). It delivers deoxygenated blood to the right atrium, as do the superior and inferior vena cava.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      44.3
      Seconds
  • Question 53 - Osteopetrosis occurs as a result of a defect in: ...

    Incorrect

    • Osteopetrosis occurs as a result of a defect in:

      Your Answer: Calcium resorption in proximal tubule

      Correct Answer: Osteoclast function

      Explanation:

      It is a metabolic bone disease caused by defective osteoclastic resorption of immature bone. Osteopetrosis is also known as marble bone disease. Osteoclasts are unable to adequately acidify bone matrix. Impaired bone resorption leads to overly dense bone that is more likely to fracture. It is usually treated with bone marrow transplant and high dose calcitriol.

    • This question is part of the following fields:

      • Connective Tissue
      • Medicine
      11.7
      Seconds
  • Question 54 - Regarding Polymerase Chain Reaction, all are true except: ...

    Incorrect

    • Regarding Polymerase Chain Reaction, all are true except:

      Your Answer: DNA polymerase extends primers using target DNA as template

      Correct Answer: There is a linear rise of DNA copies during amplification.

      Explanation:

      All are true except there is a linear rise of DNA copies during amplification. There is an exponential rise in amplification of DNA.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      6.4
      Seconds
  • Question 55 - Cholinergic vagal supply to the SA and AV nodes results in slowing of...

    Correct

    • Cholinergic vagal supply to the SA and AV nodes results in slowing of the heart rate via:

      Your Answer: M2 muscarinic receptors

      Explanation:

      M2 muscarinic receptors are the receptors for the parasympathetic system to the SA and the AV node.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      8.4
      Seconds
  • Question 56 - Which two ducts form the ampulla of Vater? ...

    Incorrect

    • Which two ducts form the ampulla of Vater?

      Your Answer: Pancreatic duct of Vater and the pancreatic duct of Wirsung

      Correct Answer: The common bile duct and the pancreatic duct of Wirsung

      Explanation:

      The ampulla of Vater, also known as the hepatopancreatic ampulla or the hepatopancreatic duct, is formed by the union of the pancreatic duct and the common bile duct. The ampulla is specifically located at the major duodenal papilla.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      8.9
      Seconds
  • Question 57 - A 24 year old male, known case of hereditary angioneurotic oedema presents with...

    Incorrect

    • A 24 year old male, known case of hereditary angioneurotic oedema presents with recurrent fever and arthralgia which is accompanied by a rash on face and upper chest. These attacks have been refractory to treatment and have occurred recurrently requiring adrenaline on several occasions. Lab results reveal persistently reduced C4 levels. Which of the following is most likely causing his current symptoms?

      Your Answer: Psoriasis with arthropathy

      Correct Answer: Systemic lupus erythematosus

      Explanation:

      Angioedema secondary to C1 inhibitor deficiency has been rarely reported to be associated with systemic lupus erythematosus. A genetic defect of C1 inhibitor produces hereditary angioedema, which is usually presented with cutaneous painless oedema, but oedema of the genital area, gastrointestinal and laryngeal tracts have also been reported. In lupus patients, angioedema may be the result of an acquired type of C1 inhibitor deficiency, most probably due to antibody formation directed against the C1 inhibitor molecule.

    • This question is part of the following fields:

      • Connective Tissue
      • Medicine
      14.5
      Seconds
  • Question 58 - Oxidation is defined as a: ...

    Incorrect

    • Oxidation is defined as a:

      Your Answer: Combination of substances with hydrogen

      Correct Answer: Loss of electrons from molecules

      Explanation:

      Oxidation is the loss of electrons or an increase in oxidation state by a molecule, atom, or ion.

    • This question is part of the following fields:

      • Medicine
      • Metabolism
      9.5
      Seconds
  • Question 59 - A 56 year old woman taking procainamide develops drug induced erythematosus. Which of...

    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: The symptoms may be alleviated with long-term steroids

      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.

    • This question is part of the following fields:

      • Connective Tissue
      • Medicine
      6.7
      Seconds
  • Question 60 - Concerning coronary arteries, what is the net effect of B2 stimulation on the...

    Incorrect

    • Concerning coronary arteries, what is the net effect of B2 stimulation on the heart (e.g. Running athlete)?

      Your Answer: Vasodilation directly

      Correct Answer: Vasodilation via production of metabolites

      Explanation:

      The coronary arterioles contain α-adrenergic receptors, which cause vasoconstriction, and β-adrenergic receptors, which cause vasodilation. Activity in the noradrenergic nerves to the heart and injections of norepinephrine cause coronary vasodilation. However, norepinephrine also increases the heart rate and the force of cardiac contraction, and the vasodilation is due to production of vasodilator metabolites in the myocardium secondary to the increase in its activity. As exercise has the same effect as sympathetic stimulation, it will result in vasodilation.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      4.5
      Seconds
  • Question 61 - Interruption of the entero-hepatic circulation causes: ...

    Incorrect

    • Interruption of the entero-hepatic circulation causes:

      Your Answer: General malabsorption

      Correct Answer: The amount of fat in the stool to be increased

      Explanation:

      Enterohepatic circulation refers to the circulation of biliary acids, bilirubin, drugs, or other substances from the liver to the bile, followed by entry into the small intestine, absorption by the enterocyte and transport back to the liver. One of the causes of the interruption of enterohepatic circulation is the resection of the ileum where fat is mainly absorbed. Fat malabsorption results in increased fat in stools. Pale stools and dark urine is caused by obstruction of the biliary ductal system especially the common bile duct where urobilin and stercobilin are formed.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      475.6
      Seconds
  • Question 62 - Transport of Iron into enterocytes occurs via which membrane transporter? ...

    Correct

    • Transport of Iron into enterocytes occurs via which membrane transporter?

      Your 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.

    • This question is part of the following fields:

      • Haematology
      • Medicine
      2.8
      Seconds
  • Question 63 - Why is the sub-endocardial portion of the left ventricle the most common site...

    Incorrect

    • Why is the sub-endocardial portion of the left ventricle the most common site for ischaemic damage and myocardial infarction?

      Your Answer: Easily hypertrophied

      Correct Answer: No blood flow occurs during systole

      Explanation:

      The subendocardium receives the least amount of blood from the coronary arteries. 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.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      5.2
      Seconds
  • Question 64 - Vitamin B12 is transported from the enterocytes to the bone marrow by which...

    Correct

    • Vitamin B12 is transported from the enterocytes to the bone marrow by which factor?

      Your Answer: Transcobalamin II (TC IIi)

      Explanation:

      B12 must be attached to IF for it to be efficiently absorbed, as receptors on the enterocytes in the terminal ileum of the small bowel only recognize the B12-IF complex. Once the IF/B12 complex is recognized by specialized ileal receptors, it is transported into the portal circulation. The vitamin is then transferred to transcobalamin II (TC-II/B12), which serves as the plasma transporter.

    • This question is part of the following fields:

      • Haematology
      • Medicine
      9
      Seconds
  • Question 65 - The parietal cells of the stomach secrete which of the following? ...

    Incorrect

    • The parietal cells of the stomach secrete which of the following?

      Your Answer: Pepsinogens

      Correct Answer: Hydrochloric acid

      Explanation:

      Parietal cells are the epithelial cells that secrete hydrochloric acid (HCl) and intrinsic factor. These cells are located in the gastric glands found in the lining of the fundus and in the body of the stomach.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      8.2
      Seconds
  • Question 66 - A 50-year-old male was under treatment for bipolar disease. He was brought to...

    Incorrect

    • A 50-year-old male was under treatment for bipolar disease. He was brought to the emergency department as he had become increasingly confused over the past two days. He had vomiting and diarrhoea. He was also consuming and passing a lot of water.On examination, he was disoriented. He had vertical nystagmus and was ataxic.What two investigations are likely to lead to the correct diagnosis?

      Your Answer: Serum lithium level

      Correct Answer: Desmopressin test and serum lithium level

      Explanation:

      Desmopressin test (done to differentiate nephrogenic diabetes insipidus from central diabetes insipidus), and serum lithium levels can together confirm a diagnosis of lithium-induced nephrogenic diabetes insipidus.Bipolar disease is most often managed with mood stabilizers like lithium. This patient develops gastrointestinal symptoms followed by an acute confusional state associated with polyuria and polydipsia. These symptoms are suggestive of diabetes insipidus.In a case where these symptoms occur in a bipolar patient under treatment, lithium-induced nephrogenic diabetes insipidus should be considered as the most probable cause.Lithium intoxication can present with symptoms of nausea, vomiting, mental dullness, action tremor, weakness, ataxia, slurred speech, blurred vision, dizziness, especially vertical nystagmus and stupor or coma. Diffuse myoclonic twitching and nephrogenic diabetes insipidus can also occur. Such a clinical syndrome occurs above the serum level of lithium of 1.5–2.0 mEq/L.Management: – Correcting electrolyte abnormalities in patients with acute disease is critical and often life-saving.- Treatment should be initiated with parenteral fluids to replete hypovolemia (normal saline at 200-250 mL/h), followed by administration of hypotonic fluid (0.5% normal saline). – On the restoration of the volume status of the patient forced diuresis should be initiated by the administration of parenteral furosemide or bumetanide accompanied by continued intravenous hypotonic fluid administration to maintain volume status.- Polyuria is managed with hydrochlorothiazide combined with amiloride, acetazolamide.

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      9.9
      Seconds
  • Question 67 - What is the blood supply to the liver? ...

    Correct

    • 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

    • This question is part of the following fields:

      • Hepatobiliary
      • Medicine
      6.8
      Seconds
  • Question 68 - The actions of thrombin result directly in the release of: ...

    Incorrect

    • The actions of thrombin result directly in the release of:

      Your Answer: 6 pairs of polypeptides from each fibrinogen molecule

      Correct Answer: Fibrin monomers

      Explanation:

      Thrombin in turn acts as a serine protease that converts soluble fibrinogen into insoluble strands of fibrin, as well as catalysing many other coagulation-related reactions.

    • This question is part of the following fields:

      • Haematology
      • Medicine
      11.9
      Seconds
  • Question 69 - Regarding the innervation of cerebral blood vessels, which of the following triggers a...

    Incorrect

    • Regarding the innervation of cerebral blood vessels, which of the following triggers a vasoconstrictor effect?

      Your Answer: CGRP

      Correct Answer: Neuropeptide-Y

      Explanation:

      Substance P is a potent vasodilator, VIP or vasoactive intestinal peptide has vasodilator properties in the intestines. PHM 27 is a potent calcitonin receptor agonist; endogenous analogue of human VIP. CGRP or Calcitonin Gene-Related Peptide is a vasodilator which is found to play an important role in migraines. Neuropeptide Y is a strong vasoconstrictor.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      13.6
      Seconds
  • Question 70 - Anti-gastroesophageal reflux mechanisms include the following except: ...

    Incorrect

    • Anti-gastroesophageal reflux mechanisms include the following except:

      Your Answer: The lower oesophageal sphincter

      Correct Answer: Peristaltic movements of the oesophagus

      Explanation:

      The lower oesophageal sphincter contracts preventing reflux of acid into the oesophagus. The sling muscles of the stomach, the crura of the diaphragm and the phreno-oesophageal ligament all play an important role in constricting the lower portion of the oesophagus and preventing reflux. Peristaltic movements do not stop the acid reflux.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      2.5
      Seconds
  • Question 71 - Which of the following do not pass through the cavernous sinus? ...

    Incorrect

    • Which of the following do not pass through the cavernous sinus?

      Your Answer: CN 4

      Correct Answer: CN 2

      Explanation:

      Oculomotor nerve (N3), trochlear nerve (N4), ophthalmic and mandibular divisions of the trigeminal nerve (N5) pass along its lateral border. The abducent nerve (N6) passes through it along with the internal carotid artery.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      8.4
      Seconds
  • Question 72 - Which part of the neuron has the highest concentration of sodium channels per...

    Correct

    • Which part of the neuron has the highest concentration of sodium channels per square millimetre of the cell membrane?

      Your Answer: Nodes of Ranvier

      Explanation:

      The nodes of Ranvier contain Na+/K+ ATPases, Na+/Ca2+ exchangers and a high density of Na+ channels. The estimated concentration of sodium channels in the node is of ∼1500/μm2.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      4.3
      Seconds
  • Question 73 - The primary sensory cortex is: ...

    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

    • This question is part of the following fields:

      • Medicine
      • Neurology
      12
      Seconds
  • Question 74 - Where is the carotid sinus located? ...

    Incorrect

    • Where is the carotid sinus located?

      Your Answer: At the start of the carotid artery

      Correct Answer: After the bifurcation of the carotid artery, on the internal carotid

      Explanation:

      The carotid sinus is a small dilation in the internal carotid artery just above its bifurcation into the external and internal carotid branch. Baroreceptors are present at this dilation.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      6.4
      Seconds
  • Question 75 - Which of the following derivatives of proopiomelanocortin is an opioid peptide? ...

    Correct

    • Which of the following derivatives of proopiomelanocortin is an opioid peptide?

      Your 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.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      4.6
      Seconds
  • Question 76 - Peristalsis is an example of: ...

    Incorrect

    • Peristalsis is an example of:

      Your Answer: None of the options

      Correct Answer: Enteric nervous system

      Explanation:

      Peristalsis is a type of contraction where radial symmetrical contraction and relaxation of muscles propagates food in a downward wave through the gut. The enteric nervous system is one of the main divisions of the nervous system and consists of a mesh-like system of neurons that controls the function of the gastrointestinal tract. It has an independent reflex activity. The neurons of this system re collected into two types of ganglia: myenteric (or Auerbach’s) and submucosal (or Meissner’s plexuses). Myenteric plexuses are located between the inner and outer layers of the muscularis externa, while submucosal plexuses are located in the submucosa.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      21.6
      Seconds
  • Question 77 - A 23 year old man presents with a painful right elbow and left...

    Incorrect

    • A 23 year old man presents with a painful right elbow and left Achilles tendon. He also gives history of dysuria, fever and conjunctivitis. Examination reveals macules and pustules on his hands. He has returned from a trip to Far East 3 weeks ago and admits to having unprotected sex. Which of the following is the most likely diagnosis?

      Your Answer: Psoriatic arthritis

      Correct Answer: Reactive arthritis

      Explanation:

      Reactive arthritis, (formerly known as Reiter’s syndrome), is an autoimmune condition that occurs after a bacterial infection of the gastrointestinal or urinary tract. It is categorized as a seronegative spondylarthritis because of its association with HLA-B27. Reactive arthritis primarily affects young men and usually presents with musculoskeletal or extra‑articular symptoms. The characteristic triad consists of arthritis, conjunctivitis, and urethritis. The diagnosis is based on clinical features such as patient history and physical examination; there are no specific tests for reactive arthritis. Treatment is primarily symptomatic and consists of the administration of NSAIDs, as most patients recover spontaneously. extraarticular dermatologic manifestations include skin lesions of the glans resembling psoriasis (balanitis circinata); hyperkeratinisation of the palms and soles (keratoderma blenorrhagicum), oral ulcers. Other STDs including HIV, syphilis have different presentations. Psoriatic arthritis is not commonly associated with urethritis and conjunctivitis.

    • This question is part of the following fields:

      • Connective Tissue
      • Medicine
      13.9
      Seconds
  • Question 78 - The bradycardia that occurs in patients with raised intracranial pressure is a result...

    Incorrect

    • The bradycardia that occurs in patients with raised intracranial pressure is a result of the?

      Your Answer: Somatosympathetic reflex

      Correct Answer: Cushing reflex

      Explanation:

      When intracranial pressure is increased, the blood supply to RVLM neurons is compromised. This results in an increase in their discharge as a result of hypoxia and hypercapnia. The resultant rise in systemic arterial pressure (Cushing reflex) tends to restore the blood flow to the medulla.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      2.8
      Seconds
  • Question 79 - There will be a proportion of people in a population who have the...

    Correct

    • There will be a proportion of people in a population who have the given condition, disease or attribute at a specified point in time or over a specified period of time. Which of following is the best term which can describe the above?

      Your Answer: Incidence

      Explanation:

      Prevalence refers to the total number of cases of a particular disease or condition present in a population at a specific point in time or over a specified period. It provides a measure of how widespread the disease or condition is within the population.

      Specificity and sensitivity are terms used to describe the accuracy of diagnostic tests.

      Probability refers to the likelihood of an event occurring.

      Incidence is a measure of how commonly or frequently a disease occurs in a specified population over a period by providing a quick measurement of new disease diagnoses.

    • This question is part of the following fields:

      • Medicine
      • Research Skills
      14.5
      Seconds
  • Question 80 - Which one of the following is necessary to activate plasminogen to plasmin? ...

    Incorrect

    • Which one of the following is necessary to activate plasminogen to plasmin?

      Your Answer: Α2-antiplasmin

      Correct Answer: tPA

      Explanation:

      In circulation, plasminogen adopts a closed, activation resistant conformation. Upon binding to clots, or to the cell surface, plasminogen adopts an open form that can be converted into active plasmin by a variety of enzymes, including tissue plasminogen activator (tPA), urokinase plasminogen activator (uPA), kallikrein, and factor XII (Hageman factor).

    • This question is part of the following fields:

      • Haematology
      • Medicine
      17.9
      Seconds
  • Question 81 - The thalamic nuclei that project over wide regions of the neocortex are: ...

    Incorrect

    • The thalamic nuclei that project over wide regions of the neocortex are:

      Your Answer: Intralaminar nuclei only

      Correct Answer: Specific relay nuclei

      Explanation:

      The thalamus is considered the relay station for sensory and motor stimuli. There are three basic types of thalamic nuclei: relay nuclei, association nuclei and non-specific nuclei. Relay nuclei receive very well defined inputs and project this signal to functionally distinct areas of the cerebral cortex. These include the nuclei that relay primary sensations and also the nuclei involved in feedback of cerebellar signals and basal gangliar output.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      5.9
      Seconds
  • Question 82 - In which stage of mitosis are the chromosomes most obvious or prominent? ...

    Correct

    • In which stage of mitosis are the chromosomes most obvious or prominent?

      Your Answer: Metaphase

      Explanation:

      Prophase begins when the nucleus envelope disintegrates and the chromosomes start to condense. The chromosomes consist of two sister chromatids that are joined at a constriction known as centromere. When the cell reaches the metaphase the chromosomes are completely condensed and ready to align on the equatorial plate.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      44.6
      Seconds
  • Question 83 - Lipid- lowering drugs like Lovastatin reduce cholesterol synthesis by inhibiting which enzyme? ...

    Correct

    • Lipid- lowering drugs like Lovastatin reduce cholesterol synthesis by inhibiting which enzyme?

      Your Answer: HMG-CoA reductase

      Explanation:

      Statins, also known as HMG-CoA reductase inhibitors, are a class of lipid-lowering medications. Statins have been found to reduce cardiovascular disease (CVD) and mortality in those who are at high risk.

    • This question is part of the following fields:

      • Medicine
      • Metabolism
      16.3
      Seconds
  • Question 84 - With regards to environmental temperature, for each degree Celsius of elevation, the metabolic...

    Incorrect

    • With regards to environmental temperature, for each degree Celsius of elevation, the metabolic rate rises?

      Your Answer: 0.12

      Correct Answer: 0.14

      Explanation:

      An increase in body temperature is associated with a higher metabolic rate. Evidence suggests that an increase of 1°C in your body temperature increases your metabolism by 10 to 14%.

    • This question is part of the following fields:

      • Medicine
      • Metabolism
      4.3
      Seconds
  • Question 85 - The residual cleft of the intermediate lobe of the pituitary is lined by...

    Incorrect

    • The residual cleft of the intermediate lobe of the pituitary is lined by follicles resembling which human gland?

      Your Answer: Parathyroid

      Correct Answer: Thyroid

      Explanation:

      The cells located between the two main pituitary lobes form what is known as the intermediate pituitary. This area secretes melanocyte-stimulating hormone and it is only a few cell layers thick. It is rich in follicles filled with colloid, and lined by basophilic cells. This configuration resembles that of another important gland: the thyroid.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      6.1
      Seconds
  • Question 86 - With regard to carbohydrate absorption, which sodium-dependent glucose transporter (SGLT) is responsible for...

    Incorrect

    • With regard to carbohydrate absorption, which sodium-dependent glucose transporter (SGLT) is responsible for the uptake of dietary glucose from the gut?

      Your Answer: SGLT 5

      Correct Answer: SGLT 1

      Explanation:

      SGLT- Sodium-dependent glucose cotransporter or sodium-glucose linked transporter are family of proteins of different types. SGLT1 transporter is found in the intestinal mucosa of the small intestine.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      11.3
      Seconds
  • Question 87 - Which cells are considered the source of IL-3? ...

    Incorrect

    • Which cells are considered the source of IL-3?

      Your Answer: Granulocytes

      Correct Answer: T lymphocytes

      Explanation:

      IL-3 stimulates haematopoiesis and is secreted mainly from the T lymphocytes.

    • This question is part of the following fields:

      • Immunology
      • Medicine
      46.1
      Seconds
  • Question 88 - A 53-year-old female teacher asks about hormone replacement therapy (HRT). What is the...

    Incorrect

    • A 53-year-old female teacher asks about hormone replacement therapy (HRT). What is the most compelling indication for starting HRT?

      Your Answer: Reversal of vaginal atrophy

      Correct Answer: Control of vasomotor symptoms such as flushing

      Explanation:

      Hormone replacement therapy (HRT) involves the use of a small dose of oestrogen, combined with a progestogen (in women with a uterus), to help alleviate menopausal symptoms. The main indication is the control of vasomotor symptoms. The other indications, such as reversal of vaginal atrophy and prevention of osteoporosis, should be treated with other agents as first-line therapies.

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      4
      Seconds
  • Question 89 - Activation of nitric oxide synthesis by endothelial cells is triggered by: ...

    Incorrect

    • Activation of nitric oxide synthesis by endothelial cells is triggered by:

      Your Answer: None of the above

      Correct Answer: All of the above

      Explanation:

      Acetylcholine, histamine, bradykinin, vasoactive intestinal peptide (VIP) and shear stress on the endothelial cells causing the release of NO. NO is formed from arginine and causes vasodilatation of the blood vessels.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      20
      Seconds
  • Question 90 - Which of the following is a characteristic clinical finding of opioid poisoning? ...

    Incorrect

    • Which of the following is a characteristic clinical finding of opioid poisoning?

      Your Answer: Deep respiration

      Correct Answer: Bradycardia

      Explanation:

      Opioid poisoning is classically associated with pinpoint pupils, reduced respiratory rate, bradycardia, drowsiness and coma. Hypothermia is a feature of barbiturate poisoning, while sweating and lacrimation are seen in cases of opiate withdrawal.

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      10.3
      Seconds
  • Question 91 - Which of the following skin conditions is not associated with diabetes mellitus? ...

    Correct

    • Which of the following skin conditions is not associated with diabetes mellitus?

      Your Answer: Sweet's syndrome

      Explanation:

      Diabetic dermadromes constitute a group of cutaneous conditions commonly seen in people with diabetes with longstanding disease. Conditions included in this group are:- Acral dry gangrene- Carotenosis- Diabetic dermopathy- Diabetic bulla- Diabetic cheiroarthropathy- Malum perforans- Necrobiosis lipoidica- Limited joint mobility- Scleroderma- Waxy skin is observed in roughly 50%. Sweet’s syndrome is also known as acute febrile neutrophilic dermatosis has a strong association with acute myeloid leukaemia. It is not associated with diabetes mellitus.

    • This question is part of the following fields:

      • Dermatology
      • Medicine
      6.4
      Seconds
  • Question 92 - A 56-year-old male presents to the emergency department with confusion and agitation for...

    Incorrect

    • 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: IV haloperidol

      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.

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      8.9
      Seconds
  • Question 93 - The pressure in the portal circulation is normally adjusted in the: ...

    Correct

    • The pressure in the portal circulation is normally adjusted in the:

      Your Answer: Sinusoids

      Explanation:

      The pressure in the portal circulation depends on the pressure of the hepatic sinusoids mainly because the direction of transport of nutrients in the portal vein occurs from the portal vein to the hepatic sinusoids.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      8.3
      Seconds
  • Question 94 - Which immunological cells are predominant in the lymph node (almost 98 % residence)?...

    Incorrect

    • Which immunological cells are predominant in the lymph node (almost 98 % residence)?

      Your Answer: Monocytes

      Correct 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.

    • This question is part of the following fields:

      • Immunology
      • Medicine
      3.1
      Seconds
  • Question 95 - An 18-year-old young lady is brought to the ER by her mother. She...

    Incorrect

    • An 18-year-old young lady is brought to the ER by her mother. She was found, lying on the floor having consumed an unidentified quantity of her mother's prescription pills with alcohol. The patient's mother is a known hypertensive under treatment. On examination, the patient was found to be lethargic, hypotensive with a BP of 70/50 mmHg, and bradycardic with a pulse rate of 38 bpm. A finger prick glucose is 3.2 mmol/L. Which TWO among the following are the most appropriate steps for the initial management of this patient?

      Your Answer: Isoprenaline and atropine

      Correct Answer: Glucagon and isoprenaline

      Explanation:

      The most appropriate steps of initial management include iv glucagon and iv isoprenaline.The most likely diagnosis in the above scenario (decreased conscious level, profound hypertension, and bradycardia) is β-blocker toxicity/overdose. Bronchospasm rarely occurs in an overdose of β-blockers, except where there is a history of asthma.Immediate management is to give iv glucagons (50–150μg/kg) followed by infusion to treat hypotension and isoprenaline or atropine to treat bradycardia. Where patients fail to respond to these measures, temporary pacing may be required. If the patient is seen within the first 4 hours of the overdose, gastric lavage may be of value.

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      8.5
      Seconds
  • Question 96 - The liver is the principal site for? ...

    Incorrect

    • The liver is the principal site for?

      Your Answer: Synthesis of steroids

      Correct Answer: Storage of iron

      Explanation:

      The liver mainly synthesizes proteins including albumin, globulins and coalgulative factors. Vitamin B12 is taken in via the diet and stored by the liver. Vitamin C is not stored and excessive vitamin C is excreted via urine. Liver is the main site of iron storage, where it is stored in the form of ferritin.

    • This question is part of the following fields:

      • Hepatobiliary
      • Medicine
      23.2
      Seconds
  • Question 97 - Emulsification of dietary lipids is brought about by ...

    Incorrect

    • Emulsification of dietary lipids is brought about by

      Your Answer: Secretin

      Correct Answer: Bile salts

      Explanation:

      Digestion of 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. 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.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      12.2
      Seconds
  • Question 98 - Which cell secretes parathyroid hormone? ...

    Incorrect

    • Which cell secretes parathyroid hormone?

      Your Answer: Parafollicular cells

      Correct Answer: Chief cells

      Explanation:

      Parathyroid chief cells, also known as parathyroid principal cells or parathyroid cells, are the most prevalent type of cell in the parathyroid gland and the only ones present at birth. They secrete parathyroid hormone (PTH).

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      7.8
      Seconds
  • Question 99 - Which is primarily responsible for the conversion of T4 to T3 in the...

    Incorrect

    • Which is primarily responsible for the conversion of T4 to T3 in the periphery?

      Your Answer: Deiodinase 2

      Correct Answer: Deiodinase 1

      Explanation:

      Type 1 iodothyronine deiodinase, also known simply as deiodinase 1, is an enzyme which can produce both triiodothyronine (active form) or inactivate metabolites from T4. It is responsible for almost 80% of the conversion of peripheral T4 to T3. Iodothyronine deiodinases are not to be confused with iodotyrosine deiodinases, which are also part of the deiodinase enzymes.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      7.9
      Seconds
  • Question 100 - A 46 year old male, known with Rheumatoid Arthritis presents with a swollen...

    Incorrect

    • 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: Urgently arrange ankle aspiration

      Correct 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.

    • This question is part of the following fields:

      • Connective Tissue
      • Medicine
      26.1
      Seconds
  • Question 101 - Which neurotransmitter is made from hydroxylation and decarboxylation of tryptophan? ...

    Incorrect

    • Which neurotransmitter is made from hydroxylation and decarboxylation of tryptophan?

      Your Answer: Histamine

      Correct Answer: Serotonin

      Explanation:

      Serotonin is synthesized from the essential amino acid tryptophan. The rate-limiting step is the conversion of the amino acid to 5-hydroxytryptophan by tryptophan hydroxylase. This is then converted to serotonin by the aromatic L-amino acid decarboxylase.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      10.1
      Seconds
  • Question 102 - Which of the following suggests the presence of mitral regurgitation as well as...

    Incorrect

    • Which of the following suggests the presence of mitral regurgitation as well as mitral stenosis?

      Your Answer: Raised JVP

      Correct Answer: Displaced apex beat

      Explanation:

      Mitral stenosis on its own does not lead to left ventricular dilatation and hence a displaced apex beat. Thus a displaced apex beat is suggestive of mixed mitral disease. The other options occur in mitral stenosis.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      5.1
      Seconds
  • Question 103 - Why does arterial blood pressure drop during pregnancy? ...

    Correct

    • Why does arterial blood pressure drop during pregnancy?

      Your 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.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      14.3
      Seconds
  • Question 104 - Angina pectoris develops when blood through the coronary artery becomes: ...

    Incorrect

    • Angina pectoris develops when blood through the coronary artery becomes:

      Your Answer: Thrombotic

      Correct Answer: Restricted, limiting blood blow

      Explanation:

      Angina pectoris develops when stenosis ( >70%) of the artery occurs as a result of formation of an atherosclerotic plaque. This leads to a decrease in the O2 carried to the thickened heart muscle by the blood, leading to the characteristic chest pain associated with angina pectoris.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      4.9
      Seconds
  • Question 105 - In cardiac muscle, which of the following is directly responsible for the release...

    Incorrect

    • In cardiac muscle, which of the following is directly responsible for the release of Ca2+ stored in the sarcoplasmic reticulum (calcium-induced calcium release)?

      Your Answer: Voltage-gated Ca2+ channels

      Correct Answer: Ryanodine receptor (RyR)

      Explanation:

      Ryanodine receptor (RyR) is a ligand-gated Ca2+ channel with Ca2+ as its natural ligand. In skeletal muscle, Ca2+ entry from ECF by this route is not required for Ca2+ release. Instead, the DHPR that serves as the voltage sensor unlocks release of Ca2+ from the nearby SR via physical interaction with the RyR. The release is amplified through ca-induced ca release. However, in cardiac muscle, it is the influx of extracellular Ca2+ through the voltage-sensitive DHPR in the T system that triggers ca-induced ca release trough the RyR at the SR.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      9.3
      Seconds
  • Question 106 - Which of the following occurs during a Valsalva manoeuvre? ...

    Correct

    • Which of the following occurs during a Valsalva manoeuvre?

      Your Answer: An initial rise in blood pressure

      Explanation:

      The Valsalva maneuver involves forced expiration against a closed glottis. It has several phases, each affecting the cardiovascular system differently:

      1. Phase I: During the initial forced expiration against the closed glottis, there is a transient rise in intrathoracic pressure, which compresses the thoracic aorta and causes a brief increase in blood pressure.
      2. Phase II: Continued straining leads to decreased venous return to the heart, reducing cardiac output and causing a drop in blood pressure. This phase is characterized by a compensatory increase in heart rate.
      3. Phase III: Upon releasing the strain, there is a sudden drop in intrathoracic pressure, which momentarily decreases blood pressure.
      4. Phase IV: Blood pressure then rises rapidly as venous return to the heart is restored, leading to increased cardiac output. This is often followed by a reflex bradycardia (slow heart rate).

      Given these phases, the most accurate statement about what occurs during the Valsalva maneuver is the initial rise in blood pressure (Phase I).

      Other options explained:

      • Forced inspiration against a closed glottis: Incorrect. The Valsalva maneuver involves forced expiration, not inspiration, against a closed glottis.
      • Low intrathoracic pressures throughout: Incorrect. The Valsalva maneuver involves high intrathoracic pressures due to forced expiration.
      • Disruption of autonomic function: Incorrect. The Valsalva maneuver affects autonomic function but does not disrupt it. Instead, it triggers autonomic responses to changes in blood pressure and heart rate.
      • No change: Incorrect. The Valsalva maneuver causes significant changes in blood pressure and heart rate.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      6.3
      Seconds
  • Question 107 - Which one of the following nerve fibers has the fastest conduction velocity? ...

    Correct

    • Which one of the following nerve fibers has the fastest conduction velocity?

      Your Answer: α fiber

      Explanation:

      α nerve fibers are characterized by being highly myelinated, which confers them with fast conduction properties. They innervate extrafusal skeletal muscle fibers, and their conduction velocity is between 80-120 m/s.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      9.6
      Seconds
  • Question 108 - Which one of the following conditions is least likely to be associated with...

    Correct

    • Which one of the following conditions is least likely to be associated with pyoderma gangrenosum?

      Your Answer: Syphilis

      Explanation:

      The following are conditions commonly associated with pyoderma gangrenosum:

      Inflammatory bowel disease:

      • Ulcerative colitis
      • Crohn’s disease

      Arthritides:

      • Rheumatoid arthritis
      • Seronegative arthritis

      Haematological disease:

      • Myelocytic leukaemia
      • Hairy cell leukaemia
      • Myelofibrosis
      • Myeloid metaplasia
      • Monoclonal gammopathy

      Autoinflammatory disease:

      • Pyogenic sterile arthritis, pyoderma gangrenosum, and acne syndrome (PAPA syndrome)
      • Granulomatosis with polyangiitis

    • This question is part of the following fields:

      • Dermatology
      • Medicine
      8.1
      Seconds
  • Question 109 - Physiological effects of T3 on the heart include all the following except: ...

    Incorrect

    • Physiological effects of T3 on the heart include all the following except:

      Your Answer: Enhanced response to circulating catecholamines

      Correct Answer: Increased expression of β-myosin heavy chain gene

      Explanation:

      Tri-iodothyronine, also known as T3, is a hormone which can affect almost every system in the human body. In the heart, it increases the number of β1-adrenergic receptors, enhances the response to circulating catecholamines, increases the proportion of α-myosin heavy chains in the atria, and increases the expression of serca pump gene.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      17
      Seconds
  • Question 110 - In the olfactory pathway: Mitral cells project to five regions of the olfactory...

    Incorrect

    • In the olfactory pathway: Mitral cells project to five regions of the olfactory cortex. Which one of the following is not one of the five regions?

      Your Answer: Piriform cortex

      Correct Answer: Posterior olfactory nucleus

      Explanation:

      The olfactory system contains peripheral and central divisions which are connected by transduction structures. Peripheral division consists mainly of the nostrils, ethmoid bone, nasal cavity, and the olfactory epithelium. Olfactory neurons are receptor cells in the epithelium that detect odour molecules dissolved in the mucus and transmit information about the odour to the brain in a process called sensory transduction. Olfactory nerves and fibers transmit information about odours from the peripheral olfactory system to the central olfactory system of the brain. The main olfactory bulb transmits pulses to both mitral and tufted cells, which help determine odour concentration. These cells also note differences between highly similar odours and use that data to aid in later recognition. The cells are different with the mitral having low firing-rates and being easily inhibited by neighbouring cells, while tufted have high rates of firing and are more difficult to inhibit. The uncus houses the olfactory cortex which includes the piriform cortex, amygdala, olfactory tubercle, and para-hippocampal gyrus. Entorhinal cortex is an area of middle temporal lobe that has connection with the para-hippocampal gyrus.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      8.8
      Seconds
  • Question 111 - Which intercellular connections are responsible for fastening the cells to one another? ...

    Correct

    • Which intercellular connections are responsible for fastening the cells to one another?

      Your Answer: Hemidesmosomes, zonula adherens & desmosomes

      Explanation:

      There are three major types of cell junction:Adherens junctions, desmosomes and hemidesmosomes (anchoring junctions),Gap junctions (communicating junction) &Tight junctions (occluding junctions)

    • This question is part of the following fields:

      • Cell Biology
      • Medicine
      8.6
      Seconds
  • Question 112 - The spleen underlies which ribs? ...

    Incorrect

    • The spleen underlies which ribs?

      Your Answer: 8 through 11

      Correct Answer: 9 through 11

      Explanation:

      The spleen lies between the 9th and 11th ribs on the left hand side.

    • This question is part of the following fields:

      • Haematology
      • Medicine
      15.5
      Seconds
  • Question 113 - A 73-year-old female is being reviewed in the osteoporosis clinic. She had a...

    Incorrect

    • A 73-year-old female is being reviewed in the osteoporosis clinic. She had a fracture of her left hip 5 years ago and was started on alendronate. Following the development of persistent musculoskeletal pain, alendronate was replaced with risedronate, which was also stopped for similar reasons. Strontium ranelate was therefore started but was also stopped due to the development of deep vein thrombosis in the right leg. Her current T-score is -4.1. A decision is made to start a trial of denosumab. What is the mechanism of action of denosumab?

      Your Answer: Monoclonal antibody against osteoprotegerin

      Correct Answer: Inhibits RANK ligand, which in turn inhibits the maturation of osteoclasts

      Explanation:

      The principal mechanism by which strontium inhibits osteoclast activity is by enhancing the secretion of osteoprotegerin (OPG) and by reducing the expression of the receptor activator of nuclear factor κB ligand (RANKL) in osteoblasts.Osteoporosis is defined as low bone mineral density caused by altered bone microstructure ultimately predisposing patients to low-impact, fragility fractures.Management:Vitamin D and calcium supplementation should be offered to all women unless the clinician is confident they have adequate calcium intake and are vitamin D repleteAlendronate is the first-line treatment. Around 25% of patients cannot tolerate alendronate, usually due to upper gastrointestinal problems. These patients should be offered risedronate or etidronate.Strontium ranelate and raloxifene are recommended if patients cannot tolerate bisphosphonates.Other medications that are useful in the treatment of osteoporosis are denosumab, teriparatide, raloxifene, etc.

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      11.2
      Seconds
  • Question 114 - Which of the following supplies the AV node? ...

    Incorrect

    • Which of the following supplies the AV node?

      Your Answer: Left coronary artery

      Correct Answer: Right coronary artery

      Explanation:

      The AV node is supplied by the right coronary artery near the origin of the posterior IV artery.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      10.4
      Seconds
  • Question 115 - Where does protein digestion begin? ...

    Incorrect

    • Where does protein digestion begin?

      Your Answer: Ileum

      Correct Answer: Stomach

      Explanation:

      Digestion typically begins in the stomach when pepsinogen is converted to pepsin by the action of hydrochloric acid, and continued by trypsin and chymotrypsin in the small intestine.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      6.1
      Seconds
  • Question 116 - Visual pathways - Choose the true statement: ...

    Incorrect

    • Visual pathways - Choose the true statement:

      Your Answer: The temporal fibers from each optic nerve decussate at the optic chiasm

      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.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      5.2
      Seconds
  • Question 117 - Where is the lower border of the liver usually found? ...

    Correct

    • Where is the lower border of the liver usually found?

      Your Answer: 10th rib anterior axillary 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.

    • This question is part of the following fields:

      • Hepatobiliary
      • Medicine
      10.5
      Seconds
  • Question 118 - Which of the following structures of the cardiac conduction system is located in...

    Incorrect

    • Which of the following structures of the cardiac conduction system is located in the right posterior portion of the interatrial septum?

      Your Answer: SA node

      Correct Answer: AV node

      Explanation:

      AV node is located at the right posterior portion of the interatrial septum.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      5.1
      Seconds
  • Question 119 - Which one of the following is not part of the WHO diagnostic criteria...

    Incorrect

    • Which one of the following is not part of the WHO diagnostic criteria for the metabolic syndrome?

      Your Answer: High triglycerides

      Correct Answer: High LDL

      Explanation:

      The World Health Organization 1999 criteria require the presence of any one of diabetes mellitus, impaired glucose tolerance, impaired fasting glucose or insulin resistance, AND two of the following:

      • Blood pressure: ≥ 140/90 mmHg
      • Dyslipidaemia: triglycerides (TG): ≥ 1.695 mmol/L and high-density lipoprotein cholesterol (HDL-C) ≤ 0.9 mmol/L (male), ≤ 1.0 mmol/L (female)
      • Central obesity: waist: hip ratio > 0.90 (male); > 0.85 (female), or body mass index > 30 kg/m2
      • Microalbuminuria: urinary albumin excretion ratio ≥ 20 µg/min or albumin: creatinine ratio ≥ 30 mg/g

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      4.6
      Seconds
  • Question 120 - Which of the following cells secrete glucagon? ...

    Correct

    • Which of the following cells secrete glucagon?

      Your Answer: A cells

      Explanation:

      Glucagon counteracts hypoglycaemia and opposes insulin by promoting gluconeogenesis and glycogenolysis. It also decreases fatty acid synthesis in the liver and adipose tissue, and promotes lipolysis. It is secreted by the pancreatic islet α-cells. Its production is regulated by the insulin produced in β-cells.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      4.9
      Seconds
  • Question 121 - The initial rapid depolarization in the action potential of cardiac muscle cells is...

    Incorrect

    • The initial rapid depolarization in the action potential of cardiac muscle cells is due to:

      Your Answer: Closure of Na+ channels

      Correct Answer: Opening of voltage-gated Na+ channels

      Explanation:

      The initial depolarization of the action potential in a cardiac muscle cell is due to the sodium current generated by opening of the voltage gated sodium channels leading to an influx of sodium ions into the cell and raising the membrane potential towards threshold.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      9.4
      Seconds
  • Question 122 - When during the cell cycle does DNA replication occur? ...

    Incorrect

    • When during the cell cycle does DNA replication occur?

      Your Answer: Cytokinesis

      Correct Answer: S phase

      Explanation:

      The S phase is known as the synthesis phase. During this phase DNA will begin to replicated, as well as the synthesis of the centrosomes and associated proteins.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      5.5
      Seconds
  • Question 123 - What is the most important way in which heat is lost from the...

    Incorrect

    • What is the most important way in which heat is lost from the body?

      Your Answer: Urination

      Correct Answer: Radiation and conduction

      Explanation:

      The body maintains a constant core temperature by balancing heat loss and heat gain. The mechanisms of heat loss are: radiation, evaporation, convection and conduction. Out of these mechanisms, the most important under normal conditions are radiation, through which body heat is given off to the surrounding atmosphere; and conduction, in which the body releases heat into the objects it comes into contact with.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      2.9
      Seconds
  • Question 124 - Select the correct statement regarding the portal vein. ...

    Incorrect

    • Select the correct statement regarding the portal vein.

      Your Answer: It enters the liver via the periphery.

      Correct Answer: It drains most of the gastrointestinal tract and the spleen.

      Explanation:

      The portal vein supplies 75% of total blood flow to the liver and enters the liver centrally via the porta hepatis. Portal venous flow increases after meals. The portal vein receives blood from the intestines via the superior and inferior mesenteric veins, from the stomach via gastric veins and from the spleen and pancreas via the splenic vein.

    • This question is part of the following fields:

      • Hepatobiliary
      • Medicine
      3.1
      Seconds
  • Question 125 - With regards to the deiodinases, where would you find D1? ...

    Incorrect

    • With regards to the deiodinases, where would you find D1?

      Your Answer: Reproductive organs

      Correct Answer: Liver

      Explanation:

      The liver produces an important amount of T3 by outer ring deiodination thanks to its elevated concentration of type I deiodinase. It can also be found in the kidney.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      4.4
      Seconds
  • Question 126 - Which of the following structures is not part of the conducting system of...

    Incorrect

    • Which of the following structures is not part of the conducting system of the heart?

      Your Answer: SA node

      Correct Answer: Ventricular wall

      Explanation:

      The conduction system of the heart consists of the SA node, AV node, internodal pathway between these two nodes, Bundle of His and the purkinje fibers

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      5.6
      Seconds
  • Question 127 - Which of the following is the most common causative organism in infective endocarditis?...

    Incorrect

    • Which of the following is the most common causative organism in infective endocarditis?

      Your Answer: Streptococcus bovis

      Correct Answer: Streptococcus viridans

      Explanation:

      Viridans Alpha-haemolytic streptococci, that are present in the mouth are the most frequently isolated microorganisms when the infection is acquired in a community setting. In contrast, Staphylococcus blood stream infections are frequently acquired in a health care setting where they can enter the blood stream through procedures that cause break in the integrity of skin like surgery, catheterisation or during access of long term indwelling catheters or secondary to intravenous injection of recreational drugs.Prosthetic valve endocarditis is commonly caused by Staphylococcus epidermidis as it is capable of growing as a biofilm on plastic surfaces

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      8
      Seconds
  • Question 128 - A 47-year-old woman diagnosed with oestrogen receptor positive breast cancer three months ago...

    Incorrect

    • A 47-year-old woman diagnosed with oestrogen receptor positive breast cancer three months ago was started on treatment with tamoxifen. Which of the following is most likely a complaint of this patient during her review today?

      Your Answer: Cervical cancer

      Correct Answer: Hot flushes

      Explanation:

      The most likely complaint of this patient would be hot flushes.

      Alopecia and cataracts are listed as possible side-effects, however they are not as prevalent as hot flushes, which are very common in pre-menopausal women.

      Tamoxifen is a Selective Oestrogen Receptor Modulator (SERM) which acts as an oestrogen receptor antagonist and partial agonist. It is used in the management of oestrogen receptor-positive breast cancer

      Adverse effects:

      • Menstrual disturbance: vaginal bleeding, amenorrhoea
      • Hot flushes – 3% of patients stop taking tamoxifen due to climacteric side-effects.
      • Venous thromboembolism.
      • Endometrial cancer (although antagonistic with respects to breast tissue, tamoxifen may serve as an agonist at other sites. Therefore the risk of endometrial cancer is increased). Raloxifene is a pure oestrogen receptor antagonist and carries a lower risk of endometrial cancer.

      Tamoxifen is typically used for 5 years following the removal of the tumour.

       

       

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      9.7
      Seconds
  • Question 129 - In Restriction Fragment Length Polymorphism (RFLP), the DNA fragments are separated by length through...

    Incorrect

    • In Restriction Fragment Length Polymorphism (RFLP), the DNA fragments are separated by length through a process known as:

      Your Answer: Insertion

      Correct Answer: Gel electrophoresis

      Explanation:

      Samples of DNA from individuals are broken into pieces by restriction enzymes and the fragments are separated according to their lengths via gel electrophoresis. Although now largely obsolete due to the rise of inexpensive DNA sequencing technologies, RFLP analysis was the first DNA profiling technique inexpensive enough to see widespread application.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      5.7
      Seconds
  • Question 130 - A 30-year-old male is brought to the emergency department following his collapse in...

    Correct

    • A 30-year-old male is brought to the emergency department following his collapse in a night club. His friends who accompanied him admit that, of recent, he has been using increasing amounts of cocaine. Which among the following is commonly associated with cocaine overdose?

      Your Answer: Metabolic acidosis

      Explanation:

      Metabolic acidosis is associated with cocaine overdose. In overdose, cocaine leads to agitation, tachycardia, hypertension, sweating, hallucinations, and finally convulsions. Metabolic acidosis, hyperthermia, rhabdomyolysis, and ventricular arrhythmias also occur.Chronic use may be associated with premature coronary artery disease, dilated cardiomyopathy, and increased risk of cerebral haemorrhage.There are 3 stages for acute cocaine toxicity:Stage I: CNS symptoms of headache, vertigo, pseudo hallucinations, hyperthermia, hypertension. Stage II: increased deep tendon reflexes, tachypnoea, irregular breathing, hypertension.Stage III: Areflexia, coma, fixed and dilated pupils, hypotension, ventricular fibrillation, apnoea, and respiratory failure.Treatment:- Airway, breathing, and circulation to be secured. The patient’s fever should be managed, and one should rule out hypoglycaemia as a cause of the neuropsychiatric symptoms. – Cardiovascular toxicity and agitation are best-treated first-line with benzodiazepines to decrease CNS sympathetic outflow.- The mixed beta/alpha blocker labetalol is safe and effective for treating concomitant cocaine-induced hypertension and tachycardia.- Non-dihydropyridine calcium channels blockers such as diltiazem and verapamil have been shown to reduce hypertension reliably, but not tachycardia. – Dihydropyridine agents such as nifedipine should be avoided, as reflex tachycardia may occur. – The alpha-blocker phentolamine has been recommended but only treats alpha-mediated hypertension and not tachycardia.

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      19.7
      Seconds
  • Question 131 - In the blood supply of the heart, ‘dominance’ refers to the coronary artery...

    Incorrect

    • In the blood supply of the heart, ‘dominance’ refers to the coronary artery which supplies the?

      Your Answer: Right atrium

      Correct Answer: Posterior interventricular artery

      Explanation:

      Dominance of the coronary artery system is defined by the artery that gives rise to the posterior interventricular artery. Dominance of the right coronary artery is more common (68%). It gives rise to the large posterior interventricular branch which goes down to the apex of the heart.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      7.7
      Seconds
  • Question 132 - In a normal heart rate at rest, the left ventricular end-diastolic volume is...

    Incorrect

    • In a normal heart rate at rest, the left ventricular end-diastolic volume is ….

      Your Answer: 50-70 ml

      Correct Answer: 100-130 ml

      Explanation:

      In cardiovascular physiology, end-diastolic volume (EDV) is the volume of blood in the right and/or left ventricle at end load or filling in (diastole) or the amount of blood in the ventricles just before systole. Because greater EDVs cause greater distention of the ventricle, EDV is often used synonymously with preload, which refers to the length of the sarcomeres in cardiac muscle prior to contraction (systole). End-diastolic volume: Right = 144 mL(± 23mL) & Left = 142 mL (± 21 mL).

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      8.4
      Seconds
  • Question 133 - At the end of which phase will P53 halt the cell cycle? ...

    Correct

    • At the end of which phase will P53 halt the cell cycle?

      Your Answer: G1 phase

      Explanation:

      P53 regulates the cell cycle. It regulates the progression from G1 to S phase

    • This question is part of the following fields:

      • Genetics
      • Medicine
      7.5
      Seconds
  • Question 134 - Role of bile salts in digestion of fats include ...

    Incorrect

    • Role of bile salts in digestion of fats include

      Your Answer: Stabilizes ph of the gastric juice

      Correct Answer: Reduce surface tension, emulsification and transportation

      Explanation:

      Bile acts to some extent as a surfactant reducing surface tension, helping to emulsify the lipids in food. Bile salt anions are hydrophilic on one side and hydrophobic on the other side; consequently, they tend to aggregate around droplets of lipids (triglycerides and phospholipids) to form micelles, with the hydrophobic sides towards the fat and hydrophilic sides facing outwards. The hydrophilic sides are negatively charged, and this charge prevents fat droplets coated with bile from re-aggregating into larger fat particles.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      8.7
      Seconds
  • Question 135 - To which of the following plasma proteins is T4 most bound in plasma?...

    Incorrect

    • To which of the following plasma proteins is T4 most bound in plasma?

      Your Answer: Transferrin

      Correct Answer: Thyroxine-binding globulin

      Explanation:

      Thyroxine-binding globulin, also known as TBG, is one of the three transport proteins responsible for carrying T4 and T3 through the circulatory system. It carries most of the T4 present in plasma, which it binds to strongly, shielding the hydrophobic hormones from the aqueous surroundings.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      8.8
      Seconds
  • Question 136 - Where is the major site of purine synthesis? ...

    Incorrect

    • Where is the major site of purine synthesis?

      Your Answer: Brain

      Correct Answer: Liver

      Explanation:

      The major site of purine synthesis is in the liver. Purines are biologically synthesized as nucleotides and in particular as ribotides.

    • This question is part of the following fields:

      • Medicine
      • Metabolism
      6.8
      Seconds
  • Question 137 - Myelin sheath in the CNS is produced by? ...

    Incorrect

    • Myelin sheath in the CNS is produced by?

      Your Answer: Neurons

      Correct Answer: Oligodendrocytes

      Explanation:

      CNS myelin is produced by special cells called oligodendrocytes. PNS myelin is produced by Schwann cells. The two types of myelin are chemically different, but they both perform the same function — to promote efficient transmission of a nerve impulse along the axon.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      14.9
      Seconds
  • Question 138 - Inactive cellular marrow is called ...

    Correct

    • Inactive cellular marrow is called

      Your Answer: Yellow marrow

      Explanation:

      The two types of bone marrow are red marrow, which consists mainly of hematopoietic tissue, and yellow marrow, which is mainly made up of fat cells.

    • This question is part of the following fields:

      • Haematology
      • Medicine
      3.4
      Seconds
  • Question 139 - In the body what are fatty acids broken down to? ...

    Incorrect

    • In the body what are fatty acids broken down to?

      Your Answer: Carnitine

      Correct Answer: Acetyl Co A

      Explanation:

      Fatty acids are broken down into acetyl Co A. The acetyl-CoA produced by beta oxidation enters the citric acid cycle in the mitochondrion by combining with oxaloacetate to form citrate.

    • This question is part of the following fields:

      • Cell Biology
      • Medicine
      24
      Seconds
  • Question 140 - A 28 year old female presents to the rheumatology clinic for review. She...

    Incorrect

    • A 28 year old female presents to the rheumatology clinic for review. She has a history of adult onset Still's disease and complains of joint pains and persistent skin rash despite undergoing treatment with methotrexate and etanercept. On examination, an erythematous macular rash and active synovitis is noted. CRP is high (95 mg/dl). Which of the following interventions would be most appropriate?

      Your Answer: Tocilizumab

      Correct Answer: Anakinra

      Explanation:

      Adult onset Still’s disease (AOSD) is an uncommon systemic inflammatory disease on the clinical spectrum of autoinflammatory disorders. Its presentation and clinical course may result in several well-differentiated phenotypes: from a systemic and highly symptomatic pattern to a chronic articular pattern. Overproduction of numerous pro-inflammatory cytokines is observed in AOSD. Anakinra, a human interleukin (IL)-1R antagonist, has recently been approved in the treatment of AOSD. Denosumab is a RANK ligand inhibitor used in the treatment of osteoporosis. Mepolizumab is used in the treatment of severe asthma with elevated eosinophils. There is some evidence to support the use of tocilizumab, an anti-IL6 monoclonal antibody in adult onset Still’s, but there is stronger data favouring the use of tocilizumab in the treatment of rheumatoid arthritis. Rituximab is usually reserved for patients who are unresponsive to anakinra.

    • This question is part of the following fields:

      • Connective Tissue
      • Medicine
      19
      Seconds
  • Question 141 - An important enzyme in renal tissue responsible for the conversion of glutamine to...

    Incorrect

    • An important enzyme in renal tissue responsible for the conversion of glutamine to glutamate and the subsequent production of NH4 is called?

      Your Answer: Glutamic reductase

      Correct Answer: Glutaminase

      Explanation:

      Glutaminase catalyses the following reaction:Glutamine + H2O → Glutamate + NH3

    • This question is part of the following fields:

      • Medicine
      • Renal
      3.7
      Seconds
  • Question 142 - In a newly diagnosed acromegaly patient, which of the following would you not...

    Incorrect

    • In a newly diagnosed acromegaly patient, which of the following would you not expect to find?

      Your Answer: Macroglossia

      Correct Answer: Hypohidrosis

      Explanation:

      Features of acromegaly may include:

      • Soft tissue swelling visibly resulting in enlargement of the hands, feet, nose, lips and ears, and a general thickening of the skin
      • Soft tissue swelling of internal organs, notably the heart with associated weakening of its muscularity, and the kidneys, vocal cords (resulting in a characteristic thick, deep voice and slowing of speech)
      • Generalized expansion of the skull at the fontanelle, frontal bossing, prognathism with associated macroglossia (enlargement of the tongue) and teeth spacing.
      • Hypertrichosis, hyperpigmentation and hyperhidrosis (not hypohidrosis) may occur in these patients as well as carpal tunnel syndrome and impotence.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      4.5
      Seconds
  • Question 143 - In a knockout mouse model the process used to combine the new DNA...

    Incorrect

    • In a knockout mouse model the process used to combine the new DNA sequence and the stem cells is known as:

      Your Answer: Chimerisation

      Correct Answer: Insertion

      Explanation:

      Chimerisation is also known as the formation of recombinant DNA. When a foreign DNA sequence is inserted into a plasmid or other DNA sequence, this process is known as insertion.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      6.6
      Seconds
  • Question 144 - The principle by which the energy of contraction is proportional to the initial...

    Incorrect

    • The principle by which the energy of contraction is proportional to the initial length of cardiac muscle fiber is known as:

      Your Answer: Direct Fick method

      Correct Answer: Starling’s law

      Explanation:

      The Frank starling relationship 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 increase 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 increased development of tension in the muscle fiber. The greater the venous return the greater the cardiac output. This relation is directly proportional.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      6.6
      Seconds
  • Question 145 - The chief cells of the stomach secrete which of the following? ...

    Incorrect

    • The chief cells of the stomach secrete which of the following?

      Your Answer: Intrinsic factor

      Correct Answer: Pepsinogens

      Explanation:

      A gastric chief cell (or peptic cell, or gastric zymogenic cell) is a type of cell in the stomach that releases pepsinogen and gastric lipase.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      11.6
      Seconds
  • Question 146 - The formation of superoxide is catalysed by which enzyme? ...

    Incorrect

    • The formation of superoxide is catalysed by which enzyme?

      Your Answer: Catalase

      Correct Answer: NADPH oxidase

      Explanation:

      Superoxide is biologically toxic and is deployed by the immune system to kill invading microorganisms. In phagocytes, superoxide is produced in large quantities by the enzyme NADPH oxidase for use in oxygen-dependent killing mechanisms of invading pathogens.

    • This question is part of the following fields:

      • Cell Biology
      • Medicine
      34.6
      Seconds
  • Question 147 - Where is retinol mainly stored? ...

    Incorrect

    • Where is retinol mainly stored?

      Your Answer: Kidneys

      Correct Answer: Liver

      Explanation:

      Vitamin A is a group of unsaturated nutritional organic compounds that includes retinol, retinal, retinoic acid, and several provitamin A carotenoids (most notably beta-carotene). The liver stores a multitude of substances, including glucose (in the form of glycogen), vitamin A (1–2 years’ supply), vitamin D (1–4 months’ supply), vitamin B12 (3–5 years’ supply), vitamin K, iron, and copper.

    • This question is part of the following fields:

      • Haematology
      • Medicine
      4.8
      Seconds
  • Question 148 - The conversion of fructose to fructose 1-phosphate is catalysed by: ...

    Incorrect

    • The conversion of fructose to fructose 1-phosphate is catalysed by:

      Your Answer: Glucokinase

      Correct Answer: Fructokinase

      Explanation:

      The first step in the metabolism of fructose is the phosphorylation of fructose to fructose 1-phosphate by fructokinase.

    • This question is part of the following fields:

      • Medicine
      • Metabolism
      10.2
      Seconds
  • Question 149 - A 28 year old male arrives at the clinic complaining of fever, arthralgia...

    Incorrect

    • 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: Tuberculous 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.

    • This question is part of the following fields:

      • Connective Tissue
      • Medicine
      4.3
      Seconds
  • Question 150 - Presence of which of the following indicates a worse prognosis in rheumatoid arthritis?...

    Incorrect

    • Presence of which of the following indicates a worse prognosis in rheumatoid arthritis?

      Your Answer: HLA DR2 allele

      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.

    • This question is part of the following fields:

      • Connective Tissue
      • Medicine
      7.3
      Seconds
  • Question 151 - A 38-year-old woman has a melanocytic naevi on her left forearm.Which of the...

    Incorrect

    • A 38-year-old woman has a melanocytic naevi on her left forearm.Which of the following features do not suggest malignant change?

      Your Answer: Increase in pigmentation

      Correct Answer: Decrease in size

      Explanation:

      Melanocytic nevi are benign neoplasms or hamartomas composed of melanocytes. Melanocytes are derived from the neural crest and migrate during embryogenesis to selected ectodermal sites (primarily the skin and the CNS), but also to the eyes and the ears.They tend to appear during early childhood and during the first 30 years of life. They may change slowly, becoming raised, changing color or gradually fading.. Pregnancy can increase the number of naevi as well as the degree of hyperpigmentation.They may become malignant and this should be suspected if the naevus increases in size, develops an irregular surface or becomes darker, itches or bleeds.

    • This question is part of the following fields:

      • Dermatology
      • Medicine
      10.9
      Seconds
  • Question 152 - A 28 year old man presents to the clinic with fatigue, exertional dyspnoea,...

    Incorrect

    • A 28 year old man presents to the clinic with fatigue, exertional dyspnoea, abdominal discomfort, xerophthalmia and xerostomia. Examination reveals enlargement of the parotid glands bilaterally, hepatomegaly and peripheral motor neuropathy. Lab results are negative for RF, ANA, SS-A and SS-B antibodies. What is the most likely diagnosis?

      Your Answer: Mixed connective tissue disease

      Correct Answer: Diffuse infiltrative lymphocytic syndrome (DILS)

      Explanation:

      The Diffuse Infiltrative Lymphocytosis Syndrome (DILS) is a rare multisystemic syndrome described in HIV-infected patients. It is characterised by CD8(+) T-cell lymphocytosis associated with a CD8(+) T-cell infiltration of multiple organs. DILS is usually seen in uncontrolled or untreated HIV infection but can also manifest itself independently of CD4(+) T-cell counts. The syndrome may present as a Sjögren-like disease that generally associates sicca signs with bilateral parotiditis, lymphadenopathy, and extra glandular organ involvement. The latter may affect the lungs, nervous system, liver, kidneys, and digestive tract. Anomalies of the respiratory system are often identified as lymphocytic interstitial pneumonia. Facial nerve palsy, aseptic meningitis or polyneuropathy are among the more frequent neurological features. Hepatic lymphocytic infiltration, lymphocytic interstitial nephropathy and digestive tract lymphocytic infiltration account for more rarely noted complications. Sicca syndrome, organomegaly and/or organ dysfunction associated with polyclonal CD8(+) T-cell organ-infiltration are greatly suggestive of DILS in people living with HIV.

    • This question is part of the following fields:

      • Connective Tissue
      • Medicine
      9.9
      Seconds
  • Question 153 - A 62 year old female complains of pain and stiffness in her shoulders....

    Incorrect

    • A 62 year old female complains of pain and stiffness in her shoulders. She also finds it difficult to get out of her chair. From the list of symptoms below, choose the one most likely to support the diagnosis of polymyalgia rheumatica.

      Your Answer: Muscle tenderness

      Correct Answer: Low grade fever

      Explanation:

      Polymyalgia rheumatica is an inflammatory disease which usually causes stiffness and pain in the shoulder – this can also occur in the pelvic girdle muscles. Its onset can either be subacute or acute and is associated with a systemic inflammatory response. This, therefore, causes symptoms such as fever, weight loss, anorexia, and malaise. Polymyalgia rheumatica is unpredictable in its course and it is known that 30 per cent of patients also present with giant cell arteritis. The cause of this disease is unknown but studies have shown it have infectious origins. Diagnosis of polymyalgia rheumatica can be difficult and other inflammatory diseases have to be excluded first. Patients with this disease are usually over 60 years of age (it is very rarely seen in those under 50). Muscle weakness does not present, although this can be hard to assess when the patient is in pain. Low-grade fever and weight loss are typical of this disease due to chronic inflammation. As such, weight gain is very rare and peripheral joints are usually not affected (they can be affected but it is very rare). Also, muscle tenderness is not a specific symptom of the disease – it is therefore not a classical finding of polymyalgia rheumatica. Although patients usually complain of stiffness and pain, the muscles are usually not significantly tender – this is usually more associated with fibromyalgia or myositis. When investigated, a normochromic/normocytic anaemia; a raised erythrocyte sedimentation rate often over 50 mm/hr., and raised C reactive protein are usually revealed. Symptoms of giant cell arteritis should also be sought, such as headaches, visual disturbances, TIAs (transient ischemic attacks), jaw claudication, and thickened temporal arteries. The patient response to a moderate dose of steroids is useful when confirming a diagnosis of polymyalgia rheumatica. The maximum dose of prednisolone should not exceed 20mg once a day. After treatment, patients should show a 70 per cent improvement in symptoms within a month (between 3-4 weeks). Inflammatory markers should also fall back to their normal levels. Non-steroidal anti-inflammatories are of little use and are associated with morbidity. There is also little evidence for the use of steroidal-sparing agents.

    • This question is part of the following fields:

      • Geriatrics
      • Medicine
      7.9
      Seconds
  • Question 154 - Amino acid reabsorption occurs most markedly in the? ...

    Incorrect

    • Amino acid reabsorption occurs most markedly in the?

      Your Answer: Distal convoluted tubule

      Correct Answer: Proximal convoluted tubule

      Explanation:

      Renal protein reabsorption is the part of renal physiology that deals with the retrieval of filtered proteins, preventing them from disappearing from the body through the urine. Almost all reabsorption takes place in the proximal tubule. Only ,1% is left in the final urine.

    • This question is part of the following fields:

      • Medicine
      • Renal
      8
      Seconds
  • Question 155 - A 32 year old man presents with blistering and hyperpigmentation on his face...

    Incorrect

    • A 32 year old man presents with blistering and hyperpigmentation on his face and hands, after a beach holiday with friends. Tests reveal high levels of uroporphyrinogen in the urine. The most likely diagnosis is:

      Your Answer: Dermatitis herpetiformis

      Correct Answer: Porphyria cutanea tarda

      Explanation:

      Porphyria cutanea tarda (PCT) is the most common of the porphyries. It is characterised by fragility and blistering of exposed skin. Typically, patients who are ultimately diagnosed with PCT first seek treatment following the development photosensitivities in the form of blisters and erosions on commonly exposed areas of the skin. This is usually observed in the face, hands, forearms, and lower legs. It heals slowly and with scarring. Though blisters are the most common skin manifestations of PCT, other skin manifestations like hyperpigmentation (as if they are getting a tan) and hypertrichosis (mainly on top of the cheeks) also occur. Risk factors for the development of PCT include alcohol and sun.

    • This question is part of the following fields:

      • Dermatology
      • Medicine
      4
      Seconds
  • Question 156 - A cohort study is being designed to look at the relationship between smoking...

    Incorrect

    • A cohort study is being designed to look at the relationship between smoking and prostate cancer. What is the usual outcome measure in a cohort study?

      Your Answer: Experimental event rate

      Correct Answer: Relative risk

      Explanation:

      A cohort study is a particular form of longitudinal study that samples a cohort (a group of people who share a defining characteristic, typically those who experienced a common event in a selected period, such as birth or graduation), performing a cross-section at intervals through time. The relative risk (RR) or risk ratio is the ratio of the probability of an outcome in an exposed group to the probability of an outcome in an unexposed group. Relative risk is used in the statistical analysis of the data of experimental, cohort and cross-sectional studies, to estimate the strength of the association between treatments or risk factors, and outcomes.

    • This question is part of the following fields:

      • Medicine
      • Research Skills
      6.9
      Seconds
  • Question 157 - Which of the following drugs requires plasma level monitoring? ...

    Incorrect

    • Which of the following drugs requires plasma level monitoring?

      Your Answer: Erythromycin

      Correct 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.

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      9.8
      Seconds
  • Question 158 - One function of the liver is synthesis and storage of protein. Which of...

    Incorrect

    • One function of the liver is synthesis and storage of protein. Which of the following will result in hypoalbuminemia?

      Your Answer: Hypercatabolic states

      Correct Answer: All of the above

      Explanation:

      Both trauma and sepsis cause an acute inflammatory response causing plasma leakage of albumin. Nephropathy causes leakage of albumin from glomeruli and excretion of albumin in urine known as albuminuria. A hypercatabolic state is characterized by increased circulating catabolic hormones and increase break down of proteins.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      3.7
      Seconds
  • Question 159 - Which of the following statements correctly describes a function of the parasympathetic innervation...

    Incorrect

    • Which of the following statements correctly describes a function of the parasympathetic innervation of the GI tract.

      Your Answer: Inhibitory efferent vagal innervation causes sphincters to contract.

      Correct Answer: Parasympathetic cholinergic activity increases the activity of intestinal smooth muscle

      Explanation:

      The parasympathetic nerves stimulate peristalsis and relax the sphincters; they also stimulate secretion. Acetylcholine is the neurotransmitter of the parasympathetic system.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      4.7
      Seconds
  • Question 160 - What is the mechanism of action of sumatriptan? ...

    Incorrect

    • What is the mechanism of action of sumatriptan?

      Your Answer: 5-HT2 agonist

      Correct Answer: 5-HT1 agonist

      Explanation:

      Triptans are specific 5-HT1 agonists used in the acute treatment of migraine. They are generally used as first-line therapy in combination with an NSAID or paracetamol.

      Sumatriptan acts as an agonist on 5-HT1B/1D receptors by inducing vasoconstriction in the basilar artery and blood vessels within the dura mater. The drug reduces peripheral nociception either by selective cranial vasoconstriction or by affecting trigeminovascular nerves.

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      6.2
      Seconds
  • Question 161 - Periodic fevers occur in humans with mutations in the gene for pyrin. Pyrin...

    Incorrect

    • Periodic fevers occur in humans with mutations in the gene for pyrin. Pyrin is a protein found in which one of the following cells?

      Your Answer: B lymphocytes

      Correct Answer: Neutrophils

      Explanation:

      Pyrin, also known as marenostrin or TRIM20, is a protein encoded by the Mediterranean fever (MEFV) gene, causing the autoinflammatory disease familial Mediterranean fever (FMF). Pyrin produces an increased sensitivity to intracellular signals. It is produced mainly in neutrophils, which display an increased ratio of cells entering apoptosis when exposed to pyrin.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      6.7
      Seconds
  • Question 162 - What landmark divides the frontal and parietal lobes? ...

    Incorrect

    • What landmark divides the frontal and parietal lobes?

      Your Answer: Corpus collosum

      Correct Answer: Central sulcus

      Explanation:

      The central sulcus divides the frontal lobe from the parietal lobe. It contains the motor cells for the movement function of the body.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      20.3
      Seconds
  • Question 163 - The p53 tumour suppressor gene is located on? ...

    Incorrect

    • The p53 tumour suppressor gene is located on?

      Your Answer: Chromosome 11

      Correct Answer: Chromosome 17

      Explanation:

      P53 is classified as a tumour suppressor gene and is located on the short arm of chromosome 17.

    • This question is part of the following fields:

      • Cell Biology
      • Medicine
      4.8
      Seconds
  • Question 164 - Which is the commonest cardiovascular abnormality seen in an adult patient with Marfan’s...

    Incorrect

    • Which is the commonest cardiovascular abnormality seen in an adult patient with Marfan’s syndrome?

      Your Answer: Mitral regurgitation

      Correct Answer: Aortic aneurysm

      Explanation:

      Marfan syndrome (MFS) is a genetic disorder of connective tissue. The degree to which people are affected varies. People with Marfan’s tend to be tall, and thin, with long arms, legs, fingers and toes. They also typically have flexible joints and scoliosis. The most serious complications involve the heart and aorta with an increased risk of mitral valve prolapse and aortic aneurysm.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      9.9
      Seconds
  • Question 165 - In the gastric mucosa, which of the following cells is known to secrete...

    Correct

    • In the gastric mucosa, which of the following cells is known to secrete gastric lipase?

      Your Answer: Chief cell

      Explanation:

      Chief cells produce pepsinogen and gastric lipase. Parietal cells produce stomach acid and intrinsic factor.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      11
      Seconds
  • Question 166 - Which of the following forms an important constituent of the brush border on...

    Incorrect

    • Which of the following forms an important constituent of the brush border on the microvilli of the intestinal epithelium?

      Your Answer: Stem cells

      Correct Answer: Hydrolases

      Explanation:

      There are certain enzymes which are part of the brush border cells including hydrolases also known as the brush border hydrolases. They perform the final step in digestion of certain nutrients.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      3.9
      Seconds
  • Question 167 - Where are the cell bodies to the preganglionic neurons located? ...

    Incorrect

    • Where are the cell bodies to the preganglionic neurons located?

      Your Answer: Forebrain

      Correct Answer: Midbrain

      Explanation:

      The cell bodies of the preganglionic neurons are located in the lateral grey column of the spinal cord and in the motor nuclei of the 3rd, 7th, 9th and 10th cranial nerves. These cranial nerves take origin from the midbrain.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      3.7
      Seconds
  • Question 168 - What is the average life span of red blood cells? ...

    Incorrect

    • What is the average life span of red blood cells?

      Your Answer: 7 hours

      Correct Answer: 4 months

      Explanation:

      Approximately 2.4 million new erythrocytes are produced per second in human adults. The cells develop in the bone marrow and circulate for about 100–120 days (4 months) in the body before their components are recycled by macrophages.

    • This question is part of the following fields:

      • Haematology
      • Medicine
      3.4
      Seconds
  • Question 169 - What is the function of the macula densa, located in the wall of...

    Incorrect

    • What is the function of the macula densa, located in the wall of the thick ascending limb?

      Your Answer: Increased solute absorption in the DCT.

      Correct Answer: Tubuloglomerular feedback.

      Explanation:

      Macula densa cells sense changes in sodium chloride level, and will trigger an autoregulatory response to increase or decrease reabsorption of ions and water to the blood (as needed) in order to alter blood volume and return blood pressure to normal. Tubuloglomerular feedback is one of several mechanisms the kidney uses to regulate glomerular filtration rate (GFR). It involves the concept of purinergic signalling, in which an increased distal tubular sodium chloride concentration causes a basolateral release of adenosine from the macula densa cells. This initiates a cascade of events that ultimately brings GFR to an appropriate level.

    • This question is part of the following fields:

      • Medicine
      • Renal
      4.5
      Seconds
  • Question 170 - The hepatic portal vein: ...

    Incorrect

    • The hepatic portal vein:

      Your Answer: Responsible for venous drainage of the liver

      Correct Answer: Carries mainly nutrients from the GIT.

      Explanation:

      The portal vein contains oxygen as any other vein in the body does. The hepatic veins are responsible for venous drainage of the liver. The main function of the portal vein is to carry absorbed nutrients in the gut for metabolism and detoxification.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      7.6
      Seconds
  • Question 171 - On which chromosome is the gene for insulin located? ...

    Correct

    • On which chromosome is the gene for insulin located?

      Your 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.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      7
      Seconds
  • Question 172 - Which of the following would provide relief from nausea and vomiting? ...

    Incorrect

    • Which of the following would provide relief from nausea and vomiting?

      Your Answer: SSRI’s

      Correct Answer: Cannabinoids

      Explanation:

      Ondansetron, chlorpromazine and haloperidol are effective antiemetic agents. Corticosteroids, cannabinoids, and benzodiazepines, alone or in combination with 5-HT3 and D2 antagonists, are also useful in the treatment of vomiting produced by chemotherapy.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      4.6
      Seconds
  • Question 173 - Calcium needed for cardiac muscle contraction is made available during which phase of...

    Incorrect

    • Calcium needed for cardiac muscle contraction is made available during which phase of the action potential?

      Your Answer: 0

      Correct 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.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      18.7
      Seconds
  • Question 174 - Blood flow to the subendocardial portions of the left ventricular muscle occurs mainly...

    Incorrect

    • Blood flow to the subendocardial portions of the left ventricular muscle occurs mainly during:

      Your Answer: Isovolumetric ventricular contraction

      Correct Answer: Diastole

      Explanation:

      The sub endocardium receives the least amount of blood from the coronary arteries. During systole the coronary arteries collapse as a result of the pressure from contraction that is exerted on them. During diastole the heart muscle relaxes and the pressure on the coronary vessels is relieved allowing blood to flow through them to the sub endocardium.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      14.8
      Seconds
  • Question 175 - Regarding CSF: ...

    Correct

    • Regarding CSF:

      Your Answer: Disruption of arachnoid villi function results in a communicating hydrocephalus

      Explanation:

      In normal adults CSF volume is around 125ml to 150ml. Turnover of the entire volume of cerebrospinal fluid is about 3 to 4 times a day. Composition of CSF is similar to that of plasma except that CSF is nearly protein-free compared with plasma and has different electrolyte levels. Blockage of the foramina causes an obstructive or non-communicating hydrocephalus. Communicating hydrocephalus or non-obstructive hydrocephalus is caused by impaired CSF reabsorption in the absence of any CSF flow obstruction.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      15.6
      Seconds
  • Question 176 - The axons of the POST ganglionic neurons are mostly? ...

    Incorrect

    • The axons of the POST ganglionic neurons are mostly?

      Your Answer: E fibers

      Correct Answer: C fibers

      Explanation:

      According to Erlanger- Grasser classification preganglionic fibers are B fibers whereas post ganglionic fibers are C fibers.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      11
      Seconds
  • Question 177 - A 20-year-old female has been admitted with an acute infection. She gives a...

    Incorrect

    • A 20-year-old female has been admitted with an acute infection. She gives a history suggestive of hypersensitivity to amoxicillin. After consultation with the allergy specialist, she has now been diagnosed with an IgE mediated penicillin allergy. Which of the following drugs should be avoided in this patient?

      Your Answer: Gentamicin

      Correct Answer: Cefalexin

      Explanation:

      Cefalexin should be avoided in this patient.This patient is known to have a severe penicillin allergy. None of the above antibiotics are penicillin based. However, 0.5 – 6.5% of patients who are proven to have an IgE mediated penicillin allergy will also be allergic to cephalosporins, including cefalexin. Penicillin, cephalosporins, and carbapenems are all members of the beta-lactam group of antibiotics and share a common beta-lactam ring. There is, therefore, a small risk of allergy cross-over between all these antibiotics. The rates of allergy cross-over are lower with second and third-generation cephalosporins than first-generation cephalosporins such as cefalexin.It is important to question the patient carefully to ascertain what symptoms they had on exposure to penicillin. Symptoms such as an urticarial rash or itching make it more likely that they have an IgE mediated allergy.

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      6.2
      Seconds
  • Question 178 - What are the diagnostic criteria for an ST segment elevation type of acute...

    Incorrect

    • What are the diagnostic criteria for an ST segment elevation type of acute myocardial infarction?

      Your Answer: 1 mm ST depression in 2 limb leads

      Correct Answer: 1 mm ST elevation in 2 limb leads

      Explanation:

      The current guidelines for the ECG diagnosis of the ST segment elevation type of acute myocardial infarction require at least 1 mm (0.1 mV) of ST segment elevation in the limb leads, and at least 2 mm elevation in the precordial leads. These elevations must be present in anatomically contiguous leads. (I, aVL, V5, V6 correspond to the lateral wall; V3-V4 correspond to the anterior wall ; V1-V2 correspond to the septal wall; II, III, aVF correspond to the inferior wall.)

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      14
      Seconds
  • Question 179 - The ability of the SA node cells to allow ionic flow through channels...

    Incorrect

    • The ability of the SA node cells to allow ionic flow through channels activated in a hyperpolarized state is known as:

      Your Answer: Depolarization

      Correct Answer: Pace maker potential

      Explanation:

      Rhythmically discharging cells have a membrane potential that, after each impulse, declines to the firing level. Thus this prepotential or Pacemaker potential triggers the next impulse. The inherent leakiness of the sinus nodal fibers to Na+ and Ca2+ causes their self excitation.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      9.7
      Seconds
  • Question 180 - Amongst the following cells, which is responsible for the secretion of defensins? ...

    Incorrect

    • Amongst the following cells, which is responsible for the secretion of defensins?

      Your Answer: Basophils

      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.

    • This question is part of the following fields:

      • Immunology
      • Medicine
      59.9
      Seconds
  • Question 181 - Coronary blood flow occurs in? ...

    Correct

    • Coronary blood flow occurs in?

      Your Answer: Diastole

      Explanation:

      Coronary arteries are unique in that they fill during diastole, when not occluded by valve cusps nor compressed by myocardial contraction).

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      2.3
      Seconds
  • Question 182 - The average end diastolic volume in a healthy individual’s ventricle is? ...

    Incorrect

    • The average end diastolic volume in a healthy individual’s ventricle is?

      Your Answer: 180 ml

      Correct Answer: 130 ml

      Explanation:

      The end diastolic volume in a healthy individual is about 130 ml.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      14.7
      Seconds
  • Question 183 - Which one of the following makes up most of the adrenal cortex? ...

    Correct

    • Which one of the following makes up most of the adrenal cortex?

      Your Answer: Zona fasciculata

      Explanation:

      The zona fasciculata represents the widest area of the adrenal cortex, situated in the middle of the cortex. It produces glucocorticoids including; 11-deoxycorticosterone, corticosterone, and cortisol.

    • This question is part of the following fields:

      • Endocrinology
      • Medicine
      15
      Seconds
  • Question 184 - Which of the following factors is not completely produced in the liver? ...

    Incorrect

    • 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.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      4.8
      Seconds
  • Question 185 - Which of the following forms the language areas of the cerebral cortex? ...

    Correct

    • Which of the following forms the language areas of the cerebral cortex?

      Your Answer: All of the above

      Explanation:

      Broca’s area, Wernicke’s area, the submarginal sulcus and the angular gyrus all form the language areas of the cerebral cortex.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      3.6
      Seconds
  • Question 186 - Which of the following drug can cause galactorrhoea? ...

    Incorrect

    • Which of the following drug can cause galactorrhoea?

      Your Answer: Atenolol

      Correct Answer: Metoclopramide

      Explanation:

      Metoclopramide causes extrapyramidal effects (especially in children and young adults), hyperprolactinaemia, and occasionally tardive dyskinesia on prolonged administration. Also reported are drowsiness, restlessness, diarrhoea, depression, neuroleptic malignant syndrome, rashes, pruritus, oedema.

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      12.5
      Seconds
  • Question 187 - Which of the following drugs would be the safest to prescribe in a...

    Incorrect

    • Which of the following drugs would be the safest to prescribe in a 22 year old man with seropositive rheumatoid arthritis who is planning to start a family?

      Your Answer: Cyclophosphamide

      Correct Answer: Prednisolone

      Explanation:

      Prednisolone although has many undesirable side effects it may be considered relatively safe compared to the drugs that are provided here. Prolonged treatment with sulphasalazine may depress semen quality and cause irreversible infertility. Methotrexate and leflunomide both inhibit purine/pyrimidine synthesis (the former by inhibiting folate metabolism) and are contraindicated in pregnancy or while trying to conceive. In males, a temporary or permanent decrease in sperm count may occur with cyclophosphamide. Because the recovery of fertility after cyclophosphamide therapy is variable, sperm banking should be considered before treatment is begun.

    • This question is part of the following fields:

      • Connective Tissue
      • Medicine
      7.8
      Seconds
  • Question 188 - Choose the correct answer: fibers in the superior cerebellar peduncle: ...

    Incorrect

    • Choose the correct answer: fibers in the superior cerebellar peduncle:

      Your Answer:

      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.

    • This question is part of the following fields:

      • Medicine
      • Neurology
      0
      Seconds
  • Question 189 - Which of the following normally has a slow depolarizing “prepotential”? ...

    Incorrect

    • Which of the following normally has a slow depolarizing “prepotential”?

      Your Answer:

      Correct Answer: Sinoatrial node

      Explanation:

      There are 2 main types of action potentials (AP) in the heart, the slow response and the fast response:The slow response is initiated by the slow calcium-sodium channels, found in the SA node (which is the natural pacemaker of the heart) and the conduction fibers of the AV node.The fast response occurs in the atrial and ventricles muscle cells and the purkinje fibers.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds
  • Question 190 - Which of the following is true of the Natriuretic hormones? ...

    Incorrect

    • Which of the following is true of the Natriuretic hormones?

      Your Answer:

      Correct Answer: They are released in response to hypervolemia

      Explanation:

      Natriuretic hormones are vasodilators released in response to hypervolemia.

      Natriuretic hormones (NH) include three groups of compounds: the natriuretic peptides NPs (ANP, BNP and CNP), the gastrointestinal peptides (guanylin and uroguanylin), and endogenous cardiac steroids. These substances induce the kidney to excrete sodium and therefore participate in the regulation of sodium and water homeostasis, blood volume, and blood pressure (BP). In addition to their peripheral functions, these hormones act as neurotransmitters or neuromodulators in the brain.

      Atrial natriuretic peptide (ANP) plays a crucial role in blood pressure regulation by inducing natriuresis and diuresis in the kidney, inhibiting renin secretion, aldosterone production, and promoting vasorelaxation.  Two paracrine factors derived from endothelial cells play important roles in modulating ANP secretion. Endothelin, a potent vasoconstrictor, stimulates ANP secretion and augments stretch induced ANP secretion. The dramatic increase in ANP release produced by cardiac ischemia appears to be mediated in part by endothelin. Nitric oxide (NO), an important vasodilator, is also produced by endothelial cells and inhibits ANP secretion.

      Brain natriuretic peptide (BNP) shares ANP’s receptor but is primarily associated with antifibrotic effects in ventricular remodeling, serving as a biomarker for heart failure and myocardial infarction.

      C-type natriuretic peptide (CNP) acts locally in an autocrine/paracrine manner, exerting potent cardiovascular effects, including vasorelaxation and vascular remodeling post-injury. NPs also demonstrate diverse effects beyond cardiovascular and renal systems, such as bronchodilation, anti-inflammatory actions, and metabolic effects on adipose tissue and long bones.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds
  • Question 191 - Catecholamines… ...

    Incorrect

    • Catecholamines…

      Your Answer:

      Correct Answer: Activate adenylyl cyclase

      Explanation:

      Norepinephrine and epinephrine activate or deactivate adenylyl cyclase resulting in a decrease or an increase in the production of cAMP.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds
  • Question 192 - A 51-year-old real estate agent takes hydrocortisone 20mg in the mornings and 5mg...

    Incorrect

    • A 51-year-old real estate agent takes hydrocortisone 20mg in the mornings and 5mg at night for Addison’s disease. The endocrinology consultant would like her to take prednisolone instead. What dose of prednisolone should be started?

      Your Answer:

      Correct Answer: 7 mg

      Explanation:

      1mg Prednisolone = 4mg hydrocortisone, so the actual equivalent daily dose is 7mg.

    • This question is part of the following fields:

      • Medicine
      • Pharmacology
      0
      Seconds
  • Question 193 - A 85 year old male with a history of faecal impaction, who lived...

    Incorrect

    • 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:

      Correct 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.

    • This question is part of the following fields:

      • Geriatrics
      • Medicine
      0
      Seconds
  • Question 194 - Adrenergic stimulation will lead to myocyte relaxation via the following mechanisms ...

    Incorrect

    • Adrenergic stimulation will lead to myocyte relaxation via the following mechanisms

      Your Answer:

      Correct Answer: Increased phosphorylation of phosholamban

      Explanation:

      Phosphorylation of phospholamban, which increases calcium ATPase activity and sequestration of calcium in the sarcoplasmic reticulum. An increased rate of relaxation is explained because cAMP also activates the protein phospholamban, situated on the membrane of the SR, that controls the rate of uptake of calcium into the SR. The latter effect explains enhanced relaxation (lusitropic effect).

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds
  • Question 195 - Bile salts are responsible for: ...

    Incorrect

    • Bile salts are responsible for:

      Your Answer:

      Correct Answer: The emulsification of fats

      Explanation:

      The main function of bile acids is to allow digestion of dietary fats and oils by acting as a surfactant that emulsifies them into micelles, allowing them to be colloidally suspended in the chyme before further processing.

    • This question is part of the following fields:

      • Hepatobiliary
      • Medicine
      0
      Seconds
  • Question 196 - An 86 year old woman accidentally inhaled her hearing aid due to her...

    Incorrect

    • An 86 year old woman accidentally inhaled her hearing aid due to her advanced Alzheimer's dementia. Upon clinical examination, her respiratory rate is found to be 35, and thus a bronchoscopy is recommended. According to which of the following would you obtain consent for this patient?

      Your Answer:

      Correct Answer: The procedure does not require a written consent

      Explanation:

      This is an emergency case regarding a patient with impaired cognitive functioning. This is why the procedure does not require a written consent. In any other case where the patient has a normal mental capacity, the consent would be obtained as an informed written consent. In this case however, the suggested procedure is almost a matter of life and death, the doctor being required to act on behalf of the patient to her optimal advantage. Under English law no other person can consent to treatment on behalf of an adult, though it is desirable that next of kin are consulted before treating an adult without consent. Recent legislation gives legal authority to people appointed by the patient, or by the state, or a relative or carer, to consent (or refuse) on behalf of the patient. A mini-mental score may not adequately identify those unable to give consent.

    • This question is part of the following fields:

      • Geriatrics
      • Medicine
      0
      Seconds
  • Question 197 - The central veins in the liver: ...

    Incorrect

    • The central veins in the liver:

      Your Answer:

      Correct Answer: Coalesce to form the hepatic vein

      Explanation:

      The central veins coalesce to form the hepatic vein which in turn drains into the inferior vena cava. The portal vein mainly carries blood from different parts of the GIT and is not drained to the inferior vena cava.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      0
      Seconds
  • Question 198 - The function of Troponin T in cardiac muscle is? ...

    Incorrect

    • The function of Troponin T in cardiac muscle is?

      Your Answer:

      Correct Answer: Allows attachment of troponin components to tropomyosin

      Explanation:

      Troponin T binds the troponin components to tropomyosin. Troponin I inhibits the interaction of myosin with actin, and troponin C contains the binding sites for the Ca2+ that helps initiate contraction.

    • This question is part of the following fields:

      • Cardiovascular
      • Medicine
      0
      Seconds
  • Question 199 - HCL is secreted by which cells in the stomach ...

    Incorrect

    • HCL is secreted by which cells in the stomach

      Your Answer:

      Correct Answer: Parietal cells

      Explanation:

      Parietal cells are the epithelial cells that secrete hydrochloric acid (HCl) and intrinsic factor. These cells are located in the gastric glands found in the lining of the fundus and in the body of the stomach.

    • This question is part of the following fields:

      • Gastrointestinal
      • Medicine
      0
      Seconds
  • Question 200 - The following cells replicate without shortening their telomeres because they express telomerase. ...

    Incorrect

    • The following cells replicate without shortening their telomeres because they express telomerase.

      Your Answer:

      Correct Answer: Germ cells

      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. During replication telomeres may be lost resulting in cell death.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      0
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Gastrointestinal (16/24) 67%
Medicine (126/186) 68%
Connective Tissue (6/11) 55%
Haematology (11/12) 92%
Immunology (3/5) 60%
Geriatrics (3/4) 75%
Genetics (4/9) 44%
Neurology (17/21) 81%
Endocrinology (9/20) 45%
Pharmacology (13/17) 76%
Cardiovascular (24/34) 71%
Infectious Diseases (1/1) 100%
Cell Biology (2/6) 33%
Metabolism (4/6) 67%
Respiratory (1/1) 100%
Hepatobiliary (4/6) 67%
Research Skills (1/2) 50%
Dermatology (4/4) 100%
Renal (3/3) 100%
Passmed