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Question 1
Incorrect
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Impulse conduction through the AV node is slow and depends on the action potential produced by which of the following.
Your Answer: All of the above
Correct Answer: Calcium flux
Explanation:The action potentials in the SA and AV nodes are largely due to Ca2+, with no contribution by Na+ influx.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 2
Correct
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In ventricular fibrillation (VF), the first defibrillation attempt (with a biphasic defibrillator) should be made at:
Your Answer: 200 J
Explanation:Defibrillation is a common treatment for life-threatening cardiac dysrhythmias and ventricular fibrillation. If the patient is in Ventricular tachycardia (VT) or ventricular fibrillation (VF) on the monitor, immediately apply the pads and shock the patient with 120-200 Joules on a biphasic defibrillator or 360 Joules on a monophasic defibrillator.
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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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VIP, GIP and somatostatin play an inhibitory role in gastric acid secretion by inactivating?
Your Answer: G cells
Explanation:Gastrin is secreted from the G cells. VIP, GIP and somatostatin all inhibit acid production by inhibiting the G cells.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 4
Correct
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With regard to X linked disorders which of the following are true
Your Answer: X linked recessive disorders usually present in males and only very rarely present in homozygous females
Explanation:All are true for autosomal recessive disorders. Dominance rules for sex-linked gene loci are determined by their behaviour in the female: because the male has only one allele (except in the case of certain types of Y chromosome aneuploidy), that allele is always expressed regardless of whether it is dominant or recessive.
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This question is part of the following fields:
- Genetics
- Medicine
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Question 5
Incorrect
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Which one of the following interventions has the least role in management of acne rosacea?
Your Answer: Camouflage creams
Correct Answer: Low-dose topical corticosteroids
Explanation:Mild cases are often not treated at all, or are simply covered up with normal cosmetics and avoiding sun exposure. Therapy for the treatment of rosacea is not curative, and is best measured in terms of reduction in the amount of facial redness and inflammatory lesions. The two primary modalities of rosacea treatment are topical and oral antibiotic agents (including metronidazole and tetracyclines). Laser therapy may be appropriate for patients with prominent telangiectasia.
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This question is part of the following fields:
- Dermatology
- Medicine
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Question 6
Incorrect
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An 80-year-old woman with advanced COPD has been admitted to the medicine ward in an unconscious state. She appears to have an acute lower respiratory tract infection. After consulting with an anaesthesiologist it was concluded that she was not a candidate for intensive care unit admission and thus, a decision was made to start the patient on doxapram therapy. Which of the following best fits the characteristics of doxapram?
Your Answer: It causes hypotension
Correct Answer: It is contraindicated in hyperthyroidism
Explanation:The two statements that fit the characteristics of doxapram are, epilepsy is a contraindication for doxapram use and concurrent use with theophylline may increase agitation.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 7
Correct
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Why is the sub-endocardial portion of the left ventricle the most common site for ischaemic damage and myocardial infarction?
Your 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.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 8
Correct
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Coronary arteries fill up during
Your Answer: Diastole
Explanation:During contraction of the ventricular myocardium (systole), the subendocardial coronary vessels (the vessels that enter the myocardium) are compressed due to the high ventricular pressures. This compression results in momentary retrograde blood flow (i.e., blood flows backward toward the aorta) which further inhibits perfusion of myocardium during systole. However, the epicardial coronary vessels (the vessels that run along the outer surface of the heart) remain open. Because of this, blood flow in the sub endocardium stops during ventricular contraction. As a result, most myocardial perfusion occurs during heart relaxation (diastole) when the subendocardial coronary vessels are open and under lower pressure.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 9
Incorrect
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Which of the following is responsible for converting inactive cortisone to active cortisol in the adrenal gland?
Your Answer: 12βHSD 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 10
Correct
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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.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 11
Correct
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Which of the following with regard to autosomal dominant disorders are true:
Your Answer: The offspring of a heterozygous individual has a 50% chance of inheriting the chromosome carrying the disease allele
Explanation:50% of the children will be effected from parents who are heterozygous for an autosomal dominant disorder. An allele can be dominant or recessive. Individuals, meanwhile, can be homozygous or heterozygous: individuals who are homozygous for a certain gene carry two copies of the same allele. individuals who are heterozygous for a certain gene carry two different alleles.
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This question is part of the following fields:
- Genetics
- Medicine
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Question 12
Correct
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Bone marrow barrier is important to:
Your Answer: Allow mature red blood cells to pass into circulation
Explanation:The blood vessels of the bone marrow constitute a barrier, inhibiting immature blood cells from leaving the marrow. Only mature blood cells contain the membrane proteins, such as aquaporin and glycophorin, that are required to attach to and pass the blood vessel endothelium.
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This question is part of the following fields:
- Haematology
- Medicine
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Question 13
Incorrect
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Choose the most correct answer, what reduces affinity for oxygen in haemoglobin?
Your Answer: Binding with 2,3 bisphosphoglycerate
Correct Answer: All the options are true
Explanation:The strength with which oxygen binds to haemoglobin is affected by several factors. These factors shift or reshape the oxyhaemoglobin dissociation curve. A rightward shift indicates that the haemoglobin under study has a decreased affinity for oxygen. The causes of shift to right can be remembered using the mnemonic, CADET, face Right! for CO2 and CO, Acid (H+), 2,3-DPG, Exercise and Temperature.
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This question is part of the following fields:
- Haematology
- Medicine
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Question 14
Correct
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A 28 year old male arrives at the clinic complaining of fever, arthralgia and urethritis. On examination, the ankle is swollen and there is a pustular rash on the dorsal foot. What is the most likely diagnosis?
Your Answer: Disseminated gonorrhoea
Explanation:DGI presents as two syndromes: 1) a bacteremic form that includes a triad of tenosynovitis, dermatitis, and polyarthralgias without purulent arthritis and 2) a septic arthritis form characterized as a purulent arthritis without associated skin lesions. Many patients will have overlapping features of both syndromes. Time from infection to clinical manifestations may range from 1 day to 3 months. There is no travel history and the rash of Lyme disease is not purulent. Reactive arthritis presents with conjunctivitis, urethritis and arthritis usually with a red hot tender and swollen joint.
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This question is part of the following fields:
- Connective Tissue
- Medicine
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Question 15
Incorrect
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Which of the following is the most common route of hepatitis B transmission worldwide?
Your Answer: Sexual transmission
Correct Answer: Perinatal transmission
Explanation:The virus is transmitted by exposure to infectious blood or body fluids. Infection around the time of birth or from contact with other people’s blood during childhood is the most frequent method by which hepatitis B is acquired in areas where the disease is common. In areas where the disease is rare, intravenous drug use and sexual intercourse are the most frequent routes of infection. Perinatal transmission is the most common and without intervention, a mother who is positive for HBsAg has a 20% risk of passing the infection to her offspring at the time of birth. This risk is as high as 90% if the mother is also positive for HBeAg.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 16
Correct
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A 85 year old male with a history of Alzheimer's dementia was brought into Casualty by family members, who stated that he had episodes of aggression. Which of the following drugs is most suitable as the pharmacological management for this presentation?
Your Answer: Risperidone
Explanation:Regarding the pharmacological management, Risperidone is the most suitable drug from the given answers as it is recommended for the treatment of aggression associated with moderate to severe Alzheimer’s disease. Quetiapine and Benzodiazepine are not recommended.
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This question is part of the following fields:
- Geriatrics
- Medicine
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Question 17
Correct
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A 39-year-old accountant with long-standing gastro-oesophageal reflux disease is reviewed in clinic. He has recently switched from ranitidine to omeprazole. What is the main benefit of omeprazole compared to ranitidine?
Your Answer: Irreversible blockade of H+/K+ ATPase
Explanation:Proton pump inhibitors can reduce gastric acid secretion by up to 99%. Acid production resumes following the normal renewal of gastric parietal cells.
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This question is part of the following fields:
- Medicine
- Pharmacology
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Question 18
Correct
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The structure of haemoglobin A in adults includes
Your Answer: Haem, globin polypeptide chains α and β
Explanation:Haemoglobin A (HbA), also known as adult haemoglobin or α2β2, is the most common human haemoglobin tetramer, comprising over 97% of the total red blood cell haemoglobin. It consists of two alpha chains and two beta chains.
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This question is part of the following fields:
- Haematology
- Medicine
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Question 19
Incorrect
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Which of the following is true with AV nodal delay?
Your Answer: The delay is about 0.01s
Correct Answer: Shortened by sympathetic stimulation
Explanation:AV nodal delay Is about 0.1s before the action potential spreads to the ventricles. It is shortened by stimulation of the sympathetic nervous system and lengthened by stimulation of the parasympathetic system.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 20
Incorrect
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What is the most important way in which heat is lost from the body?
Your Answer: Vaporisation of sweat
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.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 21
Correct
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Embryologically the anterior pituitary is formed from?
Your Answer: Rathkes pouch
Explanation:The ectoderm, located in the roof of the pharynx, forms Rathke’s pouch, which comes into contact with the ectoderm of the developing brain. The pouch eventually separates from the pharynx, becoming the anterior pituitary.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 22
Incorrect
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The process by which DNA fragments are separated by gel and transferred onto a membrane sheet is called:
Your Answer: Northern blotting
Correct Answer: Southern blotting
Explanation:A Southern blot is a method used in molecular biology for detection of a specific DNA sequence in DNA samples. Southern blotting combines transfer of electrophoresis-separated DNA fragments to a filter membrane and subsequent fragment detection by probe hybridization. The other forms of blotting involve the use of RNA and proteins.
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This question is part of the following fields:
- Genetics
- Medicine
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Question 23
Incorrect
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Medullary chemoreceptors
Your Answer: Monitor PCO2 concentration of arterial blood
Correct Answer: Monitor H+ concentration of the CSF
Explanation:Central chemoreceptors of the central nervous system, located on the ventrolateral medullary surface in the vicinity of the exit of the 9th and 10th cranial nerves, are sensitive to the pH of their environment. These act to detect the changes in pH of nearby cerebral spinal fluid (CSF) that are indicative of altered oxygen or carbon dioxide concentrations available to brain tissues.
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This question is part of the following fields:
- Medicine
- Respiratory
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Question 24
Correct
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What is the blood supply to the liver?
Your Answer: Hepatic artery and hepatic portal vein
Explanation:The liver receives a dual blood supply from the hepatic portal vein and hepatic arteries. The hepatic portal vein delivers approximately 75% of the liver’s blood supply, and carries venous blood drained from the spleen, gastrointestinal tract, and its associated organs. The hepatic arteries supply arterial blood to the liver, accounting for the remaining quarter of its blood flow. Oxygen is provided from both sources; approximately half of the liver’s oxygen demand is met by the hepatic portal vein, and half is met by the hepatic arteries
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This question is part of the following fields:
- Hepatobiliary
- Medicine
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Question 25
Correct
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A patient with a VIPoma (VIP secreting tumour) is likely to exhibit which of the following?
Your Answer: Severe diarrhoea
Explanation:Vasoactive inhibitory peptide (VIP) is found in the nerves innervating the GIT. It markedly stimulates the secretion of intestinal electrolytes and also with them water. This results in secretary diarrhoea. Along with that it also relaxes intestinal smooth muscle including the sphincters, it also results in dilation of the peripheral blood vessels and along with this its also inhibits gastric acid secretions. A VIPoma will exaggerate all this.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 26
Correct
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Which statement is correct about the clinical state of methemoglobinemia?
Your Answer: May arise due to a hereditary deficiency of NADH.
Explanation:Methaemoglobin is a form of haemoglobin that contains ferric [Fe3+] iron and has a decreased ability to bind oxygen. Spontaneously formed methaemoglobin is normally reduced by protective enzyme systems, e.g., NADH methaemoglobin reductase, hence a deficiency of NADH may result in increased levels of methaemoglobin
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This question is part of the following fields:
- Haematology
- Medicine
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Question 27
Incorrect
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When looking at the JVP what does the c wave signify:
Your Answer: Ventricular diastole
Correct Answer: Isovolumetric ventricular contraction
Explanation:The C wave signifies a rise in the atrial pressure during isovolumetric contraction due to the tricuspid valve bulging into the atria.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 28
Correct
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Which of the following provides the sympathetic nervous supply to the stomach?
Your Answer: Coeliac plexus
Explanation:Parasympathetic innervation to the stomach is from the vagus nerve and the sympathetic innervation is from the coeliac plexus.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 29
Correct
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The net effect of active Vitamin D on calcium and phosphate homeostasis is?
Your Answer: Increase in Ca, increase in phosphate
Explanation:Bone and its metabolism are regulated by several hormones, amongst which is vitamin D. It is heavily involved in the metabolism and homeostasis of calcium and phosphate through several processes. Vitamin D works in the intestine, kidney, bone and parathyroid glands to maintain levels of calcium and phosphate, promoting its absorption, bone resorption, and proper functioning of the parathyroid to maintain adequate serum calcium levels.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 30
Incorrect
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Majority of gastrinomas are found in the:
Your Answer: Pancreas
Correct Answer: Duodenum
Explanation:A gastrinoma is a tumour in the pancreas or duodenum that secretes excess of gastrin leading to ulceration in the duodenum, stomach and the small intestine. It is usually found in the duodenum, although it may arise in the stomach or pancreas. Those occurring in the pancreas have a greater potential for malignancy. Most gastrinomas are found in the gastrinoma triangle; this is bound by the junction of cystic and common bile ducts, junction of the second and third parts of the duodenum, and the junction of the neck and body of the pancreas.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 31
Correct
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Sequence of events in formation of speech are:
Your Answer: Wernicke’s area---arcuate fasciculus---broca’s area---insula---motor cortex---speech
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. Firstly, the language is accessed in the Wernicke’s area and these words are sent via the arcuate fasciculus to the Broca’s area, where instructions for articulation is generated. This is then sent from Broca’s are to the motor cortex for the articulation.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 32
Correct
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Where is thyroglobulin produced?
Your Answer: Thyrocytes
Explanation:Thyroglobulin, or Tg, is a protein that functions as the precursor to thyroid hormones. It is synthesized by thyrocytes and then secreted into the colloid. It also functions as a negative-feedback regulator of thyroid hormone biosynthesis.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 33
Correct
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Which of the following is NOT a cause of onycholysis?
Your Answer: Mycoplasma pneumonia
Explanation:Onycholysis is the separation of the distal edge of the nail from the vascular nailbed causing whiteness of the free edge. Causes include:- Idiopathic- Trauma, excessive manicuring- Infection: especially fungal- Skin disease: psoriasis, dermatitis- Impaired peripheral circulation e.g. Raynaud’s- Systemic disease: hyper/hypothyroidism, reactive arthritis, porphyria cutanea tarda- Sometimes a reaction to detergents (e.g. washing dishes with bare hands, using detergent-based shampoos or soaps).- Patients with hepatocellular dysfunction may develop hair-thinning or hair loss and nail changes such as clubbing, leukonychia (whitening), or onycholysis.
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This question is part of the following fields:
- Dermatology
- Medicine
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Question 34
Incorrect
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A 30 year old female has been started on azathioprine after she was found to be intolerant of methotrexate. Routine blood monitoring shows the following values:Hb 7.9 g/dlPlt 97*109/l WBC 2.7*109/l Azathioprine toxicity will most likely to occur in the presence of which of the following?
Your Answer: Cimetidine
Correct Answer: Thiopurine methyltransferase deficiency
Explanation:Azathioprine therapy can cause acute myelosuppression. Toxicity is in part caused by the incorporation of azathioprine-derived 6-thioguanine nucleotides (6-TGN) into deoxyribonucleic acid (DNA). The enzyme thiopurine methyltransferase (TPMT) plays an important role in azathioprine catabolism.
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This question is part of the following fields:
- Connective Tissue
- Medicine
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Question 35
Correct
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Habituation…
Your Answer: Is a simple form of learning in which a neutral stimulus is repeated many times
Explanation:It is a simple form of learning where an organism decreases or ceases it’s response to a certain stimuli after repeated presentation. The organisms learns to stop responding to a stimulus which is no longer biologically relevant.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 36
Correct
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Which of the following acute phase reactants increases the most dramatically in the first hour following injury?
Your Answer: C-reactive protein
Explanation:Measurement of acute-phase proteins, especially C-reactive protein, is a useful marker of inflammation. It correlates with the erythrocyte sedimentation rate (ESR), however not always directly. This is due to the ESR being largely dependent on elevation of fibrinogen, an acute phase reactant with a half-life of approximately one week. This protein will therefore remain higher for longer despite removal of the inflammatory stimuli. In contrast, C-reactive protein (with a half-life of 6-8 hours) rises rapidly and can quickly return to within the normal range if treatment is employed.
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This question is part of the following fields:
- Immunology
- Medicine
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Question 37
Incorrect
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The enzyme responsible for Telomeres to maintain their length after cell division is called:
Your Answer: None of the above telomeres shorten with all cell divisions
Correct Answer: Telomerase reverse transcriptase
Explanation:Telomeres are non-coding DNA consisting of repetitive nucleotide sequences plus proteins that are found at the end of the linear chromosomes. They maintain the integrity of the chromosomes and prevent their shortening.
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This question is part of the following fields:
- Genetics
- Medicine
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Question 38
Incorrect
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Regarding integrins, which option is false?
Your Answer: Can bind to ligands and stimulate secondary signals resulting in endocytosis, proliferation and apoptosis
Correct Answer: Play no role in cell signalling.
Explanation:Integrins are transmembrane receptors that facilitate cell-extracellular matrix (ECM) adhesion. Upon ligand binding, integrins activate signal transduction pathways that mediate cellular signals such as regulation of the cell cycle, organization of the intracellular cytoskeleton, and movement of new receptors to the cell membrane. Integrins are obligate heterodimers, meaning that they have two subunits: α (alpha) and β (beta). Integrins play an important role in cell signalling by modulating the cell signalling pathways of transmembrane protein kinases such as receptor tyrosine kinases (RTK).
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This question is part of the following fields:
- Cell Biology
- Medicine
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Question 39
Incorrect
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The interventricular septum is supplied anteriorly by the?
Your Answer: Right main coronary artery
Correct Answer: Left anterior descending artery
Explanation:The anterior interventricular artery or left anterior descending artery supplies the anterior 2/3rds of the interventricular septum.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 40
Incorrect
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The cerebellum consist of which three lobes?
Your Answer: Medial, lateral and superior
Correct Answer: Anterior, posterior and flocculonodular
Explanation:The cerebellum consists of 3 lobes; Anterior, Posterior and Flocculonodular lobe.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 41
Correct
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Depolarization of the T tubule membrane activates the sarcoplasmic reticulum via which receptors?
Your Answer: Dihydropyridine receptors
Explanation:Action potentials are transmitted to the fibrils of a fiber through the T tubule system. It triggers the release of Ca 2+ form the terminal cisterns. Depolarization of the T tubules activates the sarcoplasmic reticulum through the dihydropyridine receptors.
Dihydropyridine receptors (DHPRs), are voltage-gated Ca2+ channels, and ryanodine receptors (RyRs), which are intracellular Ca2+ release channels, are expressed in diverse cell types, including skeletal and cardiac muscle.
Ryanodine receptors (RyRs) are located in the sarcoplasmic/endoplasmic reticulum membrane and are responsible for the release of Ca2+ from intracellular stores during excitation-contraction coupling in both cardiac and skeletal muscle.
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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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Angina pectoris develops when blood through the coronary artery becomes:
Your 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.
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 43
Incorrect
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A 45 year old male presents with lower backache and pain in his hips. Blood tests are normal except for elevated serum alkaline phosphatase which is 1200 IU/l (45-105). Radiological examination shows combined osteolytic and osteosclerotic lesions. What is the most common site of occurrence of this disease?
Your Answer: Lumbar spine
Correct Answer: Pelvis
Explanation:The patient most likely suffers from Paget’s disease of the bone as his radiological examination shows both osteolytic and osteosclerotic lesions. Any bone or bones can be affected, but Paget’s disease occurs most frequently in the pelvis > lumbar spine > femur > thoracic spine > sacrum > skull > tibia.
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This question is part of the following fields:
- Connective Tissue
- Medicine
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Question 44
Correct
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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.
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This question is part of the following fields:
- Endocrinology
- Medicine
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Question 45
Correct
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A 78-year-old male with long-standing Alzheimer's disease is being reviewed in your clinic. Which among the following is true regarding memantine, a drug which has been approved for the management of dementia?
Your Answer: It is an NMDA-receptor antagonist
Explanation:Memantine is an antagonist of the NMDA (N-Methyl-D-Aspartate)-receptor subtype of glutamate receptor. It is used to slow the neurotoxicity thought to be involved in Alzheimer’s disease and other neurodegenerative diseases.
Drug interactions:
- When given concomitantly with other NMDA-receptor antagonists (e.g., ketamine, amantadine) there is increased risk of psychosis.
- Dopamine agonists, L-dopa, and anticholinergics enhance effects of memantine.
- Antispasmodics (e.g., baclofen) enhance effects, as memantine has some antispasmodic effects.
- Drugs excreted by cationic transporters in the kidney (e.g. quinine, cimetidine, ranitidine) reduce excretion.
- Common adverse effects include dizziness, headache, confusion, diarrhoea, and constipation.
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This question is part of the following fields:
- Medicine
- Pharmacology
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Question 46
Correct
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Which of the following acts on the pancreas to secrete pancreatic juice that is rich in enzymes?
Your Answer: CCK
Explanation:CCK (Cholecystokinin): CCK is released by the duodenum in response to the presence of fats and proteins in the small intestine. It stimulates the pancreas to secrete enzyme-rich pancreatic juice, which aids in the digestion of fats, proteins, and carbohydrates. It also stimulates the gallbladder to contract and release bile.
Secretin: Secretin is released by the duodenum in response to acidic chyme entering from the stomach. It primarily stimulates the pancreas to release bicarbonate-rich pancreatic juice to neutralize the acid, but it does not primarily stimulate enzyme secretion.
Gastrin: Gastrin is produced by G-cells in the stomach. It stimulates gastric acid secretion by the stomach, not pancreatic enzyme secretion.
Chymotrypsin: Chymotrypsin is an enzyme produced by the pancreas. It does not act to stimulate the pancreas; rather, it is a component of the pancreatic juice that helps digest proteins.
Elastase: Elastase is also an enzyme produced by the pancreas. Like chymotrypsin, it is involved in the digestion of proteins and does not stimulate the pancreas.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 47
Incorrect
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The infoldings or spaces between the bases of the villi are known as
Your Answer: Crypts of Brunner
Correct Answer: Crypts of Lieberkühn
Explanation:An intestinal gland (also crypt of Lieberkühn and intestinal crypt) is a gland found in the intestinal epithelium lining of the small intestine and large intestine (colon) between the villi.
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This question is part of the following fields:
- Gastrointestinal
- Medicine
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Question 48
Incorrect
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Which one of the following is a risk factor for torsade de pointes?
Your Answer: Hyponatraemia
Correct Answer: Hypothermia
Explanation:The following is a list of factors associated with an increased tendency toward torsades de pointes:- Hypokalaemia (low blood potassium)- Hypomagnesemia (low blood magnesium)- Hypocalcaemia (low blood calcium)- Bradycardia (slow heartbeat)- Heart failure- Left ventricular hypertrophy- Hypothermia- Subarachnoid haemorrhage- Hypothyroidism
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This question is part of the following fields:
- Cardiovascular
- Medicine
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Question 49
Correct
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Amongst the following cells, which is responsible for the secretion of defensins?
Your Answer: Neutrophils
Explanation:Eosinophils are phagocytic and they are directed against helminths. Basophils are involved in allergic reactions and contain histamine and vasoactive granules in their cytoplasm. Mast cells are similar to basophils. Monocytes differentiate into macrophages in the tissue, secret interleukins and are phagocytic. Neutrophils are phagocytic but are also responsible for secreting defensins.
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This question is part of the following fields:
- Immunology
- Medicine
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Question 50
Correct
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A 56 year old obese female presents due to moderate pain in her finger joints which occurs mostly at the end of the day which gets better with rest. There is also some associated swelling. On examination, there is enlargement of her distal interphalangeal joints and tenderness to palpation. Which of the following is the most likely diagnosis?
Your Answer: Osteoarthritis
Explanation:Osteoarthritis (OA) is a disabling joint disease characterized by a noninflammatory degeneration of the joint complex (articular cartilage, subchondral bone, and synovium) that occurs with old age or from overuse. It mainly affects the weight-bearing and high-use joints, such as the hip, knee, hands, and vertebrae. Despite the widespread view that OA is a condition caused exclusively by degenerative “wear and tear” of the joints, newer research indicates a significant heterogeneity of causation, including pre-existing peculiarities of joint anatomy, genetics, local inflammation, mechanical forces, and biochemical processes that are affected by proinflammatory mediators and proteases. Major risk factors include advanced age, obesity, previous injuries, and asymmetrically stressed joints. In early-stage osteoarthritis, patients may complain of reduced range of motion, joint-stiffness, and pain that is aggravated with heavy use. As the disease advances, nagging pain may also occur during the night or at rest. Diagnosis is predominantly based on clinical and radiological findings. Classic radiographic features of OA do not necessarily correlate with clinical symptoms and appearance. RA involves proximal interphalangeal joints not distal. Gout occurs as a result of overproduction or underexcretion of uric acid and frequently involves first toe. Fibromyalgia is a disorder characterized by widespread musculoskeletal pain accompanied by fatigue, sleep, memory and mood issues.
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This question is part of the following fields:
- Connective Tissue
- Medicine
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SESSION STATS - PERFORMANCE PER SPECIALTY
