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Question 1
Correct
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Question 2
Correct
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Regarding the myofilament molecules, which of the following contains binding sites for calcium that helps to initiate contraction?
Your Answer: Troponin c
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.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 3
Correct
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Choose the most correct missing words to complete the statement: A portion of circulating growth hormone is bound to the ____ receptor and activates the ____ pathway that mediates its effect.
Your Answer: Growth hormone receptor (extracellular domain), jak 2stat
Explanation:The growth hormone receptor is a transmembrane protein involved in the STATs, MAPK and PI3-kinase/Akt pathways. The JAK-STAT signalling pathway is activated by different ligands, such as growth hormone, interferon and interleukin. This pathway is involved in the expression of genes associated with oncogenesis, immunity, proliferation, differentiation and apoptosis. Errors in these pathways can produce leukaemia’s and other myeloproliferative disorders.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 4
Correct
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Question 5
Correct
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Which one of the following diuretics is associated with metabolic acidosis?
Your Answer: Acetazolamide
Explanation:Acetazolamide is in the diuretic and carbonic anhydrase inhibitor families of medication. It works by decreasing the amount of hydrogen ions and bicarbonate in the body and can thus cause metabolic acidosis and electrolyte changes (hypokalaemia, hyponatremia).
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This question is part of the following fields:
- Medicine
- Pharmacology
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Question 6
Correct
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Endothelial cells are attached to adjacent cells by adherent junctions via:
Your Answer: Cadherins
Explanation:Cadherins are calcium dependant molecules that mediate cell to cell adhesions in epithelial and endothelial cells among others.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 7
Correct
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Which of the following stimulates glucagon release?
Your Answer: Exercise
Explanation:Studies have shown a small increase in glucagon levels during stress tests and exercise. This occurs in response to the reduction of blood glucose levels during physical activity; epinephrine levels are also a stimulus for the release of glucagon during exercise, since it suppresses insulin, which accounts for its stimulatory effects on glucagon. The use of stored fats for energy during exercise also stimulates the release of glucagon.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 8
Correct
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Which cells secrete insulin?
Your Answer: B cells of the pancreatic islets
Explanation:Insulin is synthesised and stored by the B cells of the pancreatic islets (70% of islet cells), glucagon is synthesised and stored in the A cells (20%) and somatostatin is synthesised and stored in the D cells (10%).
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 9
Correct
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Question 10
Correct
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The residual cleft of the intermediate lobe of the pituitary is lined by follicles resembling which human gland?
Your 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.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 11
Correct
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Which heart sounds are matched correctly?
Your Answer: All of the above
Explanation:In healthy adults, there are two normal heart sounds often described as a lub and a dub (or dup), that occur in sequence with each heartbeat. These are the first heart sound (S1) and second heart sound (S2), produced by the closing of the atrioventricular valves and semilunar valves, respectively. In addition to these normal sounds, a variety of other sounds may be present including heart murmurs, adventitious sounds, and gallop rhythms S3 and S4. S3 is thought to be caused by the oscillation of blood back and forth between the walls of the ventricles initiated by blood rushing in from the atria. The reason the third heart sound does not occur until the middle third of diastole is probably that during the early part of diastole, the ventricles are not filled sufficiently to create enough tension for reverberation. S4 when audible in an adult is called a presystolic gallop or atrial gallop. This gallop is produced by the sound of blood being forced into a stiff or hypertrophic ventricle.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 12
Correct
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Question 13
Correct
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A 28 year old female with a history of psoriatic arthritis would most likely have which of the following hand conditions?
Your Answer: Nail dystrophy
Explanation:Nail dystrophy (pitting of nails, onycholysis, subungual hyperkeratosis), dactylitis, sausage shaped fingers are most commonly seen with psoriatic arthropathy. There is asymmetric joint involvement most commonly distal interphalangeal joints. Uveitis and sacroiliitis may also occur. Arthritis mutilans may occur but is very rare. Cutaneous lesions may or may not develop. When they do, its usually much after the symptoms of arthritis.
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This question is part of the following fields:
- Connective Tissue
- Medicine
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Question 14
Correct
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Which ion channel is a dimer?
Your Answer: Cl- channel
Explanation:A dimer is a chemical structure formed from two similar sub-units. Chloride channels or exchangers are composed of two similar subunits—a dimer—each subunit containing one pore.
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This question is part of the following fields:
- Cell Biology
- Medicine
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Question 15
Correct
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Calcium is mobilized from the sarcoplasmic reticulum through:
Your Answer: Ryanodine receptor (RyR2) calcium release channels
Explanation:During the plateau phase of the action potential, calcium from the extracellular fluid enters through the L type of calcium channels. This entry triggers the release of more calcium from the sarcoplasmic reticulum via the ryanodine receptors. As a result intracellular calcium increases binding to troponin C resulting in contraction.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 16
Incorrect
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Which of the following is responsible for converting inactive cortisone to active cortisol in the adrenal gland?
Your Answer: 11βHSD type 2
Correct Answer: 11βHSD type 1
Explanation:11β-Hydroxysteroid dehydrogenase, also known as HSD-11β or 11β-HSD, is a group of enzymes which catalyse the interconversion of active cortisol and corticosterone with inert cortisone and 11-dehydrocorticosterone.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 17
Correct
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Which of the following hormones cause negative feedback on the CRH/ACTH axis?
Your Answer: Cortisol
Explanation:The hypothalamic–pituitary–adrenal axis, also known as HPA axis is a set of interactions that regulate the secretion of several hormones through negative feedback. Cortisol, for example, is produced by the adrenal cortex, binds to its receptors in the hypothalamus and adenohypophysis and inhibits secretion of corticotropin releasing hormone (CRH) and adrenocorticotropic hormone (ACTH). The drop in CRH secretion leads to a decrease in ACTH secretion, which in turn causes less cortisol to be secreted.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 18
Correct
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Erythropoietin is synthesized by which cells of the nephron?
Your Answer: Tubular interstitial cells
Explanation:Erythropoietin is produced by interstitial fibroblasts in the kidney in close association with peritubular capillary and proximal convoluted tubule. It is also produced in perisinusoidal cells in the liver. While liver production predominates in the fetal and perinatal period, renal production is predominant during adulthood.
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This question is part of the following fields:
- Medicine
- Renal
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Question 19
Incorrect
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The end product of trehalase action on oligosaccharides is
Your Answer: A molecule of glucose and a molecule of fructose
Correct Answer: Two glucose molecules
Explanation:Disaccharides are glycoside hydrolases, enzymes that break down certain types of sugars called disaccharides into simpler sugars called monosaccharides.Examples of disaccharides:Lactase (breaks down lactose into glucose and galactose)Maltase (breaks down maltose into 2 glucoses)Sucrase (breaks down sucrose into glucose and fructose)Trehalase (breaks down trehalose into 2 glucoses)
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 20
Correct
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In the Fick‘s method of measuring cardiac output, the arterial oxygen content can be measured in a sample obtained from
Your Answer: The pulmonary vein
Explanation:In Fick’s original method, the following variables are measured:VO2, oxygen consumption in ml of pure gaseous oxygen per minute. This may be measured using a spirometer within a closed rebreathing circuit incorporating a CO2 absorberCa, the oxygen concentration of blood taken from the pulmonary vein (representing oxygenated blood)Cv, the oxygen concentration of blood from an intravenous cannula (representing deoxygenated blood)From these values, we know that:VO2 = (CO x Ca) – (CO x Cv)where CO = Cardiac Output, Ca = Oxygen concentration of arterial blood and Cv = Oxygen concentration of mixed venous blood.This allows us to sayCO = VO2/{Ca – Cv}and hence calculate cardiac output.Note that (Ca – Cv) is also known as the arteriovenous oxygen difference.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 21
Correct
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A 76-year-old man has been admitted with a respiratory tract infection. On examination, he was found to be confused and dyspnoeic with O2 saturation of 88%. He has a 60 pack-year smoking history. An arterial blood gas analysis reveals CO2 retention. He has been deemed unfit for admission into the intensive care unit. The physician elects to begin a doxapram infusion. Among the following statements which best fits with the characteristics of doxapram?
Your Answer: Epilepsy is a contraindication for doxapram use
Explanation:The statement that fits the characteristics of doxapram is, epilepsy is a contraindication for doxapram use. Concurrent use with theophylline may increase agitation not relaxation.Doxapram is a central respiratory stimulant. In clinical practice, doxapram is usually used for patients who have an acute exacerbation of chronic obstructive pulmonary disease (COPD) who are unsuitable for admission to the intensive therapy unit for ventilatory support. Doxapram infusion may buy an extra 24 h to allow for recovery.Contraindications include: ischaemic heart disease, epilepsy, cerebral oedema, acute stroke, asthma, hypertension, hyperthyroidism, and pheochromocytoma. The infusion may worsen agitation and dyspnoea and lead to hypertension, nausea, vomiting and urinary retention.Drug interactions:Concomitant administration of doxapram and aminophylline (theophylline) can cause increased skeletal muscle activity, agitation, and hyperactivity.
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This question is part of the following fields:
- Medicine
- Pharmacology
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Question 22
Correct
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Which statement is correct regarding mRNA?
Your Answer: mRNAs are mainly found in the nucleus and cytoplasm of a cell.
Explanation:mRNA is transcribed from DNA and is carried to the cytosol to be translated. Hence it is mainly found in the cytosol and the nucleus of a cell. It is single stranded and contains the base uracil instead of thymine.
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This question is part of the following fields:
- Genetics
- Medicine
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Question 23
Incorrect
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Which of the following is not innervated by the parasympathetic nerve supply?
Your Answer: Sphincter muscle of iris
Correct Answer: Radial muscle of iris
Explanation:The sphincter pupillae is supplied by the parasympathetic fibers from the Edinger Westphal nucleus of the oculomotor nerve. The dilator pupillae (radial muscle) is supplied by the postganglionic fibers of the superior cervical sympathetic ganglion. The parasympathetic nerve supply to the salivary glands originate in the parasympathetic nucleus of the facial nerve (superior salivatory nucleus) and the glossopharyngeal nerve (inferior salivatory nucleus). The parasympathetic preganglionic fibers originate in the dorsal nucleus of the vagus nerve and descend into the thorax in the vagus nerve. The fibers terminate by synapsing with postganglionic neurons in the cardiac plexuses. Postganglionic fibers terminate on the sinoatrial and atrioventricular nodes and on the coronary arteries Parasympathetic supply to the stomach is via the vagus nerve.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 24
Correct
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The triangle with the heart at its centre, using limb leads is called:
Your Answer: Einthoven
Explanation:The Einthoven triangle is formed by placing the limb leads on both the arms and on the left leg with the heart in the centre.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 25
Incorrect
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Regarding taste threshold and intensity discrimination:
Your Answer: 10% change in concentration of substance tasted is necessary before an intensity difference can be detected
Correct Answer: 30% change in concentration of substance tasted is necessary before an intensity difference can be detected
Explanation:The ability of humans to differentiate differences in intensity of taste is poor. A 30% change in the concentration of the substance being tasted is required before an intensity difference is perceived.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 26
Incorrect
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Which of the following causes an increase in venous return?
Your Answer: A decrease in the normal negative intra-thoracic pressure
Correct Answer: An increase in the negative intra-thoracic pressure
Explanation:During inspiration, intrathoracic pressure becomes more negative and intra-abdominal pressure more positive. This increases the venous pressure gradient from abdomen to thorax and promotes filling of the central veins.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 27
Correct
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What is the most abundant hormone release by the thyroid?
Your Answer: T4
Explanation:T3 and T4 are the two tyrosine-based hormones produced and secreted by the thyroid gland. Although T3 is the active form of the hormone, and thus, it is much more potent; T4 is the most abundant hormone secreted by the thyroid (93% of the total thyroid secretion) and it also has a longer half life since it binds to proteins much more strongly.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 28
Correct
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Which part of the cerebellum is primarily responsible for equilibrium and eye movements?
Your Answer: Vestibulocerebellum
Explanation:The vestibulocerebellum develops at the same time as the vestibular apparatus in the inner ear. Its regulates balance between agonist and antagonist muscle contractions of the spine, hips, and shoulders during rapid movements.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 29
Correct
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Which of the following is the most common clinical feature of carbon monoxide poisoning?
Your Answer: Headache
Explanation:Carbon monoxide (CO) poisoning:It is considered as the great imitator of other diseases as the patients present with a myriad of symptoms. The carbon monoxide diffuses rapidly across the pulmonary capillary membrane binding to the haem molecule with a very high affinity (240 times that of oxygen) forming carboxy-haemoglobin (COHb). Non-smokers have a baseline COHb of ,3% while smokers have a baseline COHb of 10-15%.Clinical features of carbon monoxide toxicity:Headache: 90% of cases (most common clinical feature)Nausea and vomiting: 50%Vertigo: 50%Confusion: 30%Subjective weakness: 20%Severe toxicity: ‘pink’ skin and mucosa, hyperpyrexia, arrhythmias, extrapyramidal features, coma, deathCherry red skin is a sign of severe toxicity and is usually a post-mortem finding.Management• 100% oxygen• Hyperbaric oxygen therapy (HBOT)The use of Hyperbaric oxygen therapy (HBOT) for treatment mild to moderate CO poisoning is not routine.The selection criteria for HBOT in cases of CO poisoning include:• COHb levels > 20-25%• COHb levels > 20% in pregnant patient • Loss of consciousness• Severe metabolic acidosis (pH <7.1)• Evidence of end-organ ischemia (e.g., ECG changes, chest pain, or altered mental status)
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This question is part of the following fields:
- Medicine
- Pharmacology
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Question 30
Correct
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A 75 year old man was brought to the clinic by his wife because lately he has lost interest in activities he previously enjoyed. His wife is worried and claims he's generally withdrawn. What would exclude depression in favour of dementia?
Your Answer: Urinary incontinence
Explanation:Urinary incontinence is not a usual symptom of depression. A depressed patient is usually capable of maintaining control of his body sphincters. In dementia, however, urinary incontinence is an important and late symptom of the disease, non-related to any urinary tract pathology. It is rather related to the cognitive impairment caused by dementia.
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This question is part of the following fields:
- Geriatrics
- Medicine
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Question 31
Correct
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The Wiebel-Palade body found in the endothelial cells is responsible for the production and release of which factor?
Your Answer: Von Willebrand factor
Explanation:Weibel-Palade bodies are the storage granules of endothelial cells, the cells that form the inner lining of the blood vessels and heart. They store and release two principal molecules, von Willebrand factor and P-selectin, and thus play a dual role in haemostasis and inflammation.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 32
Correct
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During the gastric phase, the acid secretion process is stimulated in the G cells by?
Your Answer: Vagal stimulation, distention of the stomach wall, oligopeptides in the stomach
Explanation:Before the meal enters into the stomach, the amount of secretion is limited. Swallowing of a food bolus triggers the release of gastrin. Once in the stomach, the meal physically distends the stomach activating the stretch receptors and initiating the vago vagal reflex amplifying the secretion during the gastric phase.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 33
Correct
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Stimulation of the carotid sinus results in:
Your Answer: Drop in blood pressure
Explanation:Stimulation of the carotid sinus will result in an increase in the baroreceptor discharge. This will travel via the afferent nerves to the medulla. Signals will pass through the vagus nerve to decrease the sympathetic outflow to the heart and the blood vessels. This inhibition will result in vasodilation of the blood vessels, venodilation and bradycardia hence decreasing the total peripheral resistance and lowering the blood pressure.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 34
Correct
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The cells that secrete HCL are found in which part of the stomach?
Your Answer: Body
Explanation:The stomach can be divided in to different regions. Cardia, fundus, body, antrum and pylorus from proximal end to distal end respectively. Different cell types are distributed accordingly among the regions of the stomach. Cells that secret HCl in the gastric mucosa are known as parietal cells and are abundant in the gastric body region. They have receptors for acetylcholine stimulated via the vagus nerve, histamine receptors and gastrin receptors which stimulate gastric acid secretion. G cells that secret gastrin are abundant in the antrum.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 35
Correct
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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: 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.
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This question is part of the following fields:
- Dermatology
- Medicine
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Question 36
Correct
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The function of the Golgi apparatus is
Your 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.
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This question is part of the following fields:
- Cell Biology
- Medicine
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Question 37
Incorrect
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A 23 year old male patient presents with urethritis for the last 2 weeks that has not responded to antibiotics. Lately he has developed an onset of new range of symptoms that are linked to his HLA B27 positivity. Which of the following signs is not related to Reiter's syndrome?
Your Answer: Pustular lesions on the soles of the feet
Correct Answer: A mild fever with a generalised macular rash
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. Dermatologic manifestations include skin lesions of the glans resembling psoriasis (balanitis circinata); hyperkeratinisation of the palms and soles (keratoderma blenorrhagicum)
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This question is part of the following fields:
- Connective Tissue
- Medicine
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Question 38
Correct
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Which of the following regulates the calcium release channels?
Your Answer: Calstabin 2
Explanation:Ca2+ is released from the SR through a Ca2+ release channel, a cardiac isoform of the ryanodine receptor (RyR2), which controls intracytoplasmic [Ca2+] and, as in vascular smooth-muscle cells, leads to the local changes in intracellular [Ca2+] called calcium sparks. A number of regulatory proteins, including calstabin 2, inhibit RyR2 and, thereby, the release of Ca2+ from the SR.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 39
Correct
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Which of the following is true regarding platelets?
Your Answer: Normally have a half-life of about 8 days
Explanation:Platelets have no cell nucleus: they are fragments of cytoplasm that are derived from the megakaryocytes of the bone marrow, and then enter the circulation. They have a half life of 5-9 days.
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This question is part of the following fields:
- Haematology
- Medicine
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Question 40
Incorrect
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A 28 year old man was rushed to the hospital after experiencing sudden onset chest pain while playing football. He has never felt such pain in the past. However, one of his uncles had a similar sudden discomfort at a young age and he passed away following a heart problem. The following vitals are recorded on examination:BP: 101/74 mmHgRR: 22 breaths/minPR: 87 beats/min Physical examination reveals abnormally long fingers and on asking the man to hold the opposite wrist, the thumb and little finger overlap each other. He is not taking any medication regularly and past medical/surgical history is not significant. He admits to smoking half pack of cigarettes/day for the last 10 years but denies abusing any illicit drugs. Which of the following explanation most likely explains the disease process in this man?
Your Answer: Decrease in the production of collagen
Correct Answer: A defect of the glycoprotein structure which usually wraps around elastin
Explanation:Aortic dissection is defined as separation of the layers within the aortic wall. Tears in the intimal layer result in the propagation of dissection (proximally or distally) secondary to blood entering the intima-media space. This can be caused as a result of both congenital or acquired factors like chronic uncontrolled hypertension. This patient shows no sign of hypertension but his physical examination hints towards Marfan Syndrome. Marfan syndrome (MFS) is an autosomal dominant connective tissue disorder affecting the microfibrils and elastin in connective tissue throughout the body. MFS is associated with pathological manifestations in the cardiovascular system (e.g., mitral valve prolapse, aortic aneurysm, and dissection), the musculoskeletal system (e.g., tall stature with disproportionately long extremities, joint hypermobility), and the eyes (e.g., subluxation of the lens of the eye). Decreased collagen production occurs in ageing, hydroxylation defects are present in vitamin C deficiency, copper deficiency affecting lysyl oxidase enzyme occurs in Menke’s disease.
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This question is part of the following fields:
- Connective Tissue
- Medicine
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Question 41
Correct
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Arterioles stemming from the coronary artery can also empty into the heart directly via the:
Your Answer: Arteriosinusoidal vessels
Explanation:Most of the venous blood returns to the heart via the coronary sinus and the anterior cardiac veins. Apart from these there are other vessels that drain directly into the heart chambers. They include arteriosinusoidal vessels, which connect the arterioles to the heart chambers. The thebesian veins drain the capillaries into the chambers and the arterioluminal vessels drain small arteries directly into the chambers.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 42
Correct
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Cells mediating innate immunity include:
Your Answer: Natural killer cells
Explanation:Natural killer cells have features of both innate and adaptive immunity. They play an important part in defence against tumours and viruses. They are non specific and do not generate immunological memory
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This question is part of the following fields:
- Immunology
- Medicine
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Question 43
Correct
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The following determines the strength of contraction
Your Answer: Plateau phase
Explanation:The plateau phase which follows is unique to myocytes and results from a small, but sustained inward calcium current through L-type calcium channels lasting 200-400 ms. This calcium influx is caused by a combined increase in permeability of the cell and especially the sarcolemmal membranes to calcium. This plateau (or refractory) phase in myocyte action potential prevents early reactivation of the myocytes and directly determines the strength of contraction
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 44
Correct
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What is the function of gap junctions?
Your Answer: Diffusion of small molecules between neighbouring cells
Explanation:Gap junctions are a specialized intercellular connection between a multitude of cell-types. They directly connect the cytoplasm of two cells, which allows various molecules, ions and electrical impulses to directly pass through a regulated gate between cells.
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This question is part of the following fields:
- Cell Biology
- Medicine
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Question 45
Correct
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“Ploidy” is a term used to refer to the number of chromosomes in cells. Cancer cells are commonly:
Your Answer: Aneuploidy
Explanation:Cancer cells most commonly undergo disordered cell growth and cell division. This results in an additional number of chromosomes called aneuploidy. This is a characteristic of cancer cells along with variation in differentiation of the cells.
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This question is part of the following fields:
- Genetics
- Medicine
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Question 46
Correct
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A 62-year-old software developer with lung cancer is currently taking MST 30mg bd for pain relief. What dose of oral morphine solution should he be prescribed for breakthrough pain?
Your Answer: 10 mg
Explanation:The total daily morphine dose is 30 x 2 = 60 mg. Therefore, the breakthrough dose should be one-sixth of this, 10 mg.
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This question is part of the following fields:
- Medicine
- Pharmacology
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Question 47
Correct
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Question 48
Correct
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Question 49
Incorrect
-
A 42 year old female presents with morning stiffness that usually takes an hour to settle and a one year history of intermittent pain and swelling of the small joints of her hands. Examination reveals symmetric soft tissue swelling over the PIP and MCP joints and rheumatoid nodules on the elbows. There is also an effusion of both wrists. Lab results are positive for rheumatoid factor. X-ray of the wrists and hands shows erosions and bony decalcification. NSAIDs are started and the patient is referred to a rheumatologist for consideration of DMARD. Previous history is significant for TB. Which of the following should be avoided?
Your Answer: leflunomide
Correct Answer: Infliximab
Explanation:Anti-TNF-α therapy is effective for patients with arthritis but it can oftentimes lead to the reactivation of latent TB. Hence it should be used with great caution in patients with a past history of TB or current infection.
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This question is part of the following fields:
- Connective Tissue
- Medicine
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Question 50
Correct
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Which factor produced by the endothelium is responsible for the regulation of vascular cell growth?
Your Answer: Vascular endothelial growth factor (VEGF)
Explanation:VEGF is produced by the endothelial cells and is the major growth factor responsible for causing vasculogenesis. Some isoforms of this growth factor also have a prominent role in formation of lymphatic vessels.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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SESSION STATS - PERFORMANCE PER SPECIALTY
