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Question 1
Correct
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Excessive gastric acid output is detected in a patient with a history of recurrent stomach ulcers. It's possible that the patient has Zollinger-Ellison syndrome.Which of the following statements about stomach acid is correct?
Your Answer: The proton pump located in the canalicular membrane is vital to its secretion
Explanation:The stomach produces gastric acid, which is a digesting fluid. The stomach secretes about 2-3 litres every day. It is involved in tissue breakdown, the conversion of pepsinogen to active pepsin, and the creation of soluble salts with calcium and iron, and has a pH range of 1.5-3.5. It also serves as an immune system by destroying microbes.The following substances are found in gastric acid:WaterAcid hydrochloridePepsinogenmucous Intrinsic factorThe parietal cells in the proximal 2/3 (body) of the stomach release gastric acid. The concentration of hydrogen ions in parietal cell secretions is 1-2 million times that of blood. Chloride is released against both a concentration and an electric gradient, and active transport is required for the parietal cell to produce acid.The following is how stomach acid is secreted:1. Gastric acid secretion is dependent on the H+/K+ ATPase (proton pump) situated in the canalicular membrane. The breakdown of water produces hydrogen ions within the parietal cell. The hydroxyl ions produced in this reaction mix quickly with carbon dioxide to generate bicarbonate ions. Carbonic anhydrase is the enzyme that catalyses this process.2. In return for chloride, bicarbonate is carried out of the basolateral membrane. The ‘alkaline tide’ occurs when bicarbonate is released into the bloodstream, resulting in a modest rise in blood pH. The parietal cell’s intracellular pH is maintained by this procedure. Conductance channels carry chloride and potassium ions into the lumen of canaliculi.3. Through the action of the proton pump, hydrogen ions are pushed out of the cell and into the lumen in exchange for potassium; potassium is thus efficiently recycled.4. The canaliculi accumulate osmotically active hydrogen ions, which creates an osmotic gradient across the membrane, allowing water to diffuse outward.
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This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
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Question 2
Correct
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What kind of function loss do you anticipate in a 22-year-old guy who had a laceration to his arm, resulting in nerve damage in the antecubital fossa?
Your Answer: Opposition of thumb
Explanation:The symptoms of median nerve injury include tingling or numbness in the forearm, thumb, and three adjacent fingers, as well as gripping weakness and the inability to move the thumb across the palm. Because the thenar muscles and the flexor pollicis longus are paralyzed, flexion, abduction, and opposition of the thumb at the MCPJ and IPJ are gone.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 3
Correct
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What is the primary function of the mitochondria?
Your Answer: The production of the cell's supply of chemical energy
Explanation:The mitochondria is responsible for the production of the cell’s supply of chemical energy. It does this by using molecular oxygen, sugar and small fatty acid molecules to generate adenosine triphosphate (ATP) by a process ss known as oxidative phosphorylation. An enzyme called ATP synthase is required. Transcription of ribosomal RNA occurs in the nucleolusProduction of messenger RNA occur in the nucleusProduction of lysosome occurs in the Golgi apparatusThe post-translational processing of newly made proteins occurs in the endoplasmic reticulum
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This question is part of the following fields:
- Basic Cellular Physiology
- Physiology
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Question 4
Correct
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The role of the juxtaglomerular (granular) cells of the juxtaglomerular apparatus is:
Your Answer: Production of renin
Explanation:Juxtaglomerular cells synthesise renin. These cells are specialised smooth muscle cells that are located in the walls of the afferent arterioles, and there are some in the efferent arterioles.
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This question is part of the following fields:
- Physiology
- Renal
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Question 5
Incorrect
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All of the following statements are correct regarding the management of acute asthma in adults except:
Your Answer: Routine prescription of antibiotics is not indicated for patients with acute asthma.
Correct Answer: Intravenous aminophylline has been shown to result in significant additional bronchodilation compared to standard care.
Explanation:There usually isn’t any additional bronchodilation with intravenous (IV) aminophylline compared to standard care with inhaled bronchodilators and steroids. IV aminophylline may cause side effects such as arrhythmias and vomiting. However, some additional benefit may be gained in patients with near-fatal asthma or life-threatening asthma with a poor response to initial therapy (5 mg/kg loading dose over 20 minutes unless on maintenance oral therapy, then continuous infusion of 0.5 – 0.7 mg/kg/hr).
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This question is part of the following fields:
- Pharmacology
- Respiratory
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Question 6
Correct
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A 60-year-old female presents with fatigue, easy bruising and repeated chest and skin infections for five months. She also complains about several episodes of nosebleeds over the last few days without any history of trauma. Her complete blood count shows the following results: Hb 9 g/dlTotal leukocyte count: 2.5x10^9/L, 1100 neutrophils/ųLMCV 100platelet count of 90,000/ųL. Which one of the following conditions does this patient most likely have?
Your Answer: Myelodysplastic syndrome
Explanation:Myelodysplastic syndromes are a group of clonal haematopoietic disorders which are characterised by anaemia, leukopenia and thrombocytopenia. Patients will complain of fatigue, symptoms of thrombocytopenia such as nosebleeds and easy bleeding and a history of repeated infections due to low white blood cells (especially Neutrophils). In Chronic lymphocytic leukaemia production of hematopoietic cells goes on for a longer time. Folate and B12 deficiency would result in hypersegmented neutrophils and a raised MCV. Iron deficiency anaemia would not cause neutropenia or thrombocytopenia.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 7
Correct
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A 72 year old man is brought to ED by ambulance with sudden onset chest pain, palpitations and shortness of breath. His HR is 160 bpm and BP 90/65. ECG demonstrates new-onset fast atrial fibrillation. Which of the following is the first-line treatment option in this case:
Your Answer: Synchronised DC cardioversion
Explanation:All patients with adverse features suggesting life-threatening haemodynamic instability (shock, syncope, heart failure, myocardial ischaemia) caused by new onset atrial fibrillation should undergo emergency electrical cardioversion with synchronised DC shock without delaying to achieve anticoagulation.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 8
Incorrect
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The most common source of healthcare-associated bacteraemia is:
Your Answer: Urinary catheter
Correct Answer: Intravenous cannula
Explanation:Healthcare-associated bacteraemia is most commonly caused by intravenous access. Any intravenous device that is left in place for a long time increases the risk of infection. It allows bacteria like Staphylococcus aureus and Staphylococcus epidermidis to enter the body.
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This question is part of the following fields:
- Microbiology
- Principles
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Question 9
Incorrect
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A patient is diagnosed as having a glucagonoma. Her blood serum glucagon concentration is 1246 pg/mL.Glucagon INHIBITS which of the following processes? Select ONE answer only.
Your Answer: Gluconeogenesis
Correct Answer: Glycolysis
Explanation:Glucagon is a peptide hormone that is produced and secreted by alpha cells of the islets of Langerhans, which are located in the endocrine portion of the pancreas. The main physiological role of glucagon is to stimulate hepatic glucose output, thereby leading to increases in glycaemia. It provides the major counter-regulatory mechanism to insulin in maintaining glucose homeostasis.Hypoglycaemia is the principal stimulus for the secretion of glucagon but may also be used as an antidote in beta-blocker overdose and in anaphylaxis in patients on beta-blockers that fail to respond to adrenaline. Glucagon then causes:GlycogenolysisGluconeogenesisLipolysis in adipose tissueThe secretion of glucagon is also stimulated by:AdrenalineCholecystokininArginineAlanineAcetylcholineThe secretion of glucagon is inhibited by:InsulinSomatostatinIncreased free fatty acidsIncreased urea productionGlycolysis is the metabolic pathway that converts glucose into pyruvate. The free energy released by this process is used to form ATP and NADH. Glycolysis is inhibited by glucagon, and glycolysis and gluconeogenesis are reciprocally regulated so that when one cell pathway is activated, the other is inactive and vice versa.Glucagon has a minor effect of enhancing lipolysis in adipose tissue. Lipolysis is the breakdown of lipids and involves the hydrolysis of triglycerides into glycerol and free fatty acids. It makes fatty acids available for oxidation.
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 10
Correct
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A 59-year-old man presents with a goitre, increased sweating, weight loss, and palpitations. A diagnosis of hyperthyroidism is suspected.What is the most appropriate first-line investigation?
Your Answer: TSH level
Explanation:A thyroid function test is used in the diagnosis of hyperthyroidism.Serum TSH should be the first-line investigation for patients with suspected hyperthyroidism as it has the highest sensitivity and specificity for hyperthyroidism. A normal TSH level almost always excludes the diagnosis, though there are rare exceptions to this.Antithyroglobulin antibodies are commonly present in Graves’ disease, but the test has a sensitivity of 98% and specificity of 99, and is not widely available.Radioactive iodine uptake scan using iodine-123 – shows low uptake in thyroiditis but high in Graves’ disease and toxic multinodular goitre. It is however, not first-line investigation in this caseThyroid ultrasound scan – is a cost-effective and safe alternative to the radioactive iodine uptake scan.
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 11
Incorrect
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Which of the following is NOT a typical clinical feature of sickle cell disease:
Your Answer: Acute chest syndrome
Correct Answer: Neutropaenia
Explanation:Features of sickle cell disease include:Anaemia (symptoms are usually mild because the O2 dissociation curve of Hb S is shifted to the right)Vaso-occlusive crisisVisceral sequestration crisisAplastic crisisIncreased susceptibility to infectionOther clinical features: Pigment gallstones with cholecystitisChronic leg ulcersAvascular necrosis of the femoral and humeral heads or other bonesCardiomyopathyPulmonary hypertensionProliferative retinopathyPriapismRenal papillary necrosisStroke
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This question is part of the following fields:
- Haematology
- Pathology
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Question 12
Incorrect
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A 30-year-old man presents with piriformis syndrome pain, tingling, and numbness in her buttocks. He noted that the pain gets worse upon sitting down. He was seen by a physiotherapist and a diagnosis of piriformis syndrome was made.Which of the following nerves becomes irritated in piriformis syndrome?
Your Answer: Nerve to piriformis
Correct Answer: Sciatic nerve
Explanation:Piriformis syndrome is a clinical condition of sciatic nerve entrapment at the level of the ischial tuberosity. While there are multiple factors potentially contributing to piriformis syndrome, the clinical presentation is fairly consistent, with patients often reporting pain in the gluteal/buttock region that may shoot, burn or ache down the back of the leg (i.e. sciatic-like pain). In addition, numbness in the buttocks and tingling sensations along the distribution of the sciatic nerve is not uncommon. The sciatic nerve runs just adjacent to the piriformis muscle, which functions as an external rotator of the hip. Hence, whenever the piriformis muscle is irritated or inflamed, it also affects the sciatic nerve, which then results in sciatica-like pain.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 13
Correct
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The cutaneous circulation's principal role is thermoregulation. This process is aided by the existence of arteriovenous anastomoses.Which of the following anatomical areas has the greatest number of arteriovenous anastomoses?Â
Your Answer: Pinna of the ear
Explanation:Short vessels called arteriovenous anastomoses (AVAs) link tiny arteries and veins. They have a large lumen diameter. The strong and muscular walls allow AVAs to completely clog the vascular lumen, preventing blood flow from artery to vein (acting like a sphincter). When the AVAs open, they create a low-resistance connection between arteries and veins, allowing blood to flow into the limbs’ superficial venous plexuses. There is no diffusion of solutes or fluid into the interstitium due to their strong muscle walls.AVAs are densely innervated by adrenergic fibres from the hypothalamic temperature-regulation centre. High sympathetic output occurs at normal core temperatures, inducing vasoconstriction of the AVAs and blood flow through the capillary networks and deep plexuses. When the temperature rises, sympathetic output decreases, producing AVA vasodilation and blood shunting from the artery to the superficial venous plexus. Heat is lost to the environment as hot blood rushes near to the skin’s surface.AVAs are a specialized anatomical adaptation that can only be found in large quantities in the fingers, palms, soles, lips, and pinna of the ear.
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This question is part of the following fields:
- Cardiovascular Physiology
- Physiology
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Question 14
Correct
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Which of the following laboratory findings is NOT typical of von Willebrand disease (VWD):
Your Answer: Thrombocytopaenia
Explanation:Laboratory findings typically show (although this varies depending on VWD type):Abnormal PFA-100 testLow factor VIII levels (if low a factor VIII/VWF binding assay is performed)Prolonged APTT (or normal)Normal PTLow VWF levelsDefective platelet aggregationNormal platelet count
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This question is part of the following fields:
- Haematology
- Pathology
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Question 15
Incorrect
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Which of the following is caused by an alpha-1 antitrypsin deficiency?
Your Answer: Cystic fibrosis
Correct Answer: Early onset emphysema
Explanation:Mucus contains chemicals such as alpha-1-antitrypsin, lysozyme, and IgA that protect the airway from pathogens and damaging proteases released from dead bacteria and immune cells. Early-onset emphysema results from a genetic deficit of alpha-1-antitrypsin, which is caused by unregulated protease activity in the lungs, which results in the degradation of elastin in the alveoli.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 16
Incorrect
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Regarding gentamicin, which of the following statements is INCORRECT:
Your Answer: Gentamicin is indicated for treatment of infective endocarditis.
Correct Answer: Gentamicin typically causes acute glomerulonephritis in toxicity.
Explanation:Gentamicin is the aminoglycoside of choice in the UK and is used widely for the treatment of serious infections. It has a broad spectrum but is inactive against anaerobes and has poor activity against haemolytic streptococci and pneumococci. When used for the blind therapy of undiagnosed serious infections it is usually given in conjunction with a penicillin or metronidazole (or both). The main toxic effects are nephrotoxicity and ototoxicity due to damage to the vestibulocochlear nerve (CN VIII).Gentamicin is contraindicated in myasthenia gravis and should be used with caution in renal disease which may result in accumulation and a greater risk of toxic side effects.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 17
Correct
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If a lesion is observed in Broca's area, which function is expected to become affected?
Your Answer: Formation of words
Explanation:The primary functions of the Broca area are both language production and comprehension. While the exact role in the production is still unclear, many believe that it directly impacts the motor movements to allow for speech. Although originally thought to only aid in speech production, lesions in the area can rarely be related to impairments in the comprehension of language. Different regions of the Broca area specialize in various aspects of comprehension. The anterior portion helps with semantics, or word meaning, while the posterior is associated with phonology, or how words sound. The Broca area is also necessary for language repetition, gesture production, sentence grammar and fluidity, and the interpretation of others’ actions.Broca’s aphasia is a non-fluent aphasia in which the output of spontaneous speech is markedly diminished and there is a loss of normal grammatical structure. Specifically, small linking words, conjunctions, such as and, or, and but, and the use of prepositions are lost. Patients may exhibit interjectional speech where there is a long latency, and the words that are expressed are produced as if under pressure. The ability to repeat phrases is also impaired in patients with Broca’s aphasia. Despite these impairments, the words that are produced are often intelligible and contextually correct. In pure Broca’s aphasia, comprehension is intact.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 18
Correct
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Continuous capillaries are typically found where in the body:
Your Answer: Blood-brain barrier
Explanation:Continuous capillaries, found in the skin, lungs, muscles and CNS, are the most selective with low permeability, as junctions between the endothelial cells are very tight, restricting the flow of molecules with MW > 10,000.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 19
Correct
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A patent has weakness of humeral flexion and extension. A CT scan reveals that he has suffered damage to the nerve that innervates pectoralis major.Pectoralis major receives its innervation from which of the following nerves? Select ONE answer only.
Your Answer: Lateral and medial pectoral nerves
Explanation:Pectoralis major is a thick, fan-shaped muscle situated in the chest. It makes up the bulk of the chest musculature in the male and lies underneath the breast in the female. It overlies the thinner pectoralis minor muscle.Superficial muscles of the chest and arm showing pectoralis major (from Gray’s Anatomy)Pectoralis major has two heads; the clavicular head and the sternocostal head. The clavicular head originates from the anterior border and medial half of the clavicle. The sternocostal head originates from the anterior surface of the sternum, the superior six costal cartilages and the aponeurosis of the external oblique muscle. It inserts into the lateral lip of the bicipital groove of the humerus.Pectoralis major receives dual innervation from the medial pectoral nerve and the lateral pectoral nerve.Its main actions are as follows:Flexes humerus (clavicular head)Extends humerus (sternocostal head)Adducts and medially rotates the humerusDraws scapula anteriorly and inferiorly
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 20
Incorrect
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A 36-year-old man presented to the emergency room with a two-week history of shortness of breath, fevers, and malaise. A chest X-ray was ordered and the results confirmed the diagnosis of a right middle lobe pneumonia. Which of the following structures of the heart lies closest to the consolidation?
Your Answer: Left atrium
Correct Answer: Right atrium
Explanation:In its typical anatomical orientation, the heart has 5 surfaces formed by different internal divisions of the heart:Anterior (or sternocostal) – Right ventriclePosterior (or base) – Left atriumInferior (or diaphragmatic) – Left and right ventriclesRight pulmonary – Right atriumLeft pulmonary – Left ventricleThe silhouette sign of Felson is with respect to the right middle lobe. The right heart border should have a distinct appearance due to the right atrium abutting aerated right middle lobe. The consolidation in the right middle lobe has resulted in loss of this silhouette.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 21
Incorrect
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A patient with a central line in situ for the past 10 days now has erythema surrounding the catheter insertion site and shows signs of sepsis. You suspect line sepsis.Which of these antibacterial agents would be most appropriate to prescribe for this patient?
Your Answer: Co-amoxiclav
Correct Answer: Vancomycin
Explanation:The current recommendation by NICE and the BNF is to use vancomycin as first-line in treatment of septicaemia related to vascular catheter. A broad-spectrum antipseudomonal beta-lactam antibiotic should be added to vancomycin if a Gram-negative sepsis is suspected especially in an immunocompromised patient.In any patient that has had a central venous catheter in situ for a period longer than a week, it should be suspected as the source of sepsis.The features suggesting the vascular catheter as the source of infection include:Presence of the catheter before onset of fever.The absence of another identifiable source of infection.Presence of inflammation or purulent material at the insertion site or along the tunnel.An immunocompetent patient without any underlying disease developing bacteraemia (or fungaemia).
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This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
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Question 22
Correct
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Regarding Gaussian sample distribution, which of the following statements is false?
Your Answer: It can be skewed left or right
Explanation:Gaussian distribution, also known as normal distribution, is the most important probability distribution in statistics because it fits many natural phenomena. The normal distribution is a probability function that describes how the values of a variable are distributed. Below are its characteristics:(1) Bell-shaped and symmetrical about the mean(2) The mean, median, mode are all equal(3) The total area under the curve and above the x-axis is equal to 1(4) It has long tapering tails extending infinitely but never touching the x-axis(5) It is determined by its parameters: its mean and standard deviation(6) The standard deviation becomes a more meaningful quality than merely being a measure of dispersionThe mean is the most common measure of central tendency. It is the sum of all observed values divided by the number of observation, and is also known as the ‘average’.The median is the value that falls in the middle position when the observations are ranked in order from the smallest to the largest. If the number of observations is odd, the median is the middle number. If it is even, the median is the average of the two middle numbers.The mode is the value that occurs with the greatest frequency in a set of observations, and is commonly used in public health statistics, such as the top 10 causes of mortality.
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This question is part of the following fields:
- Evidence Based Medicine
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Question 23
Correct
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A 50-year-old man presents with headaches, lethargy, hypertension, and electrolyte disturbance. A diagnosis of primary hyperaldosteronism is made.Which biochemical pictures would best support this diagnosis?
Your Answer: Hypokalaemic metabolic alkalosis
Explanation:When there are excessive levels of aldosterone outside of the renin-angiotensin axis, primary hyperaldosteronism occurs. High renin levels will lead to secondary hyperaldosteronism. The classical presentation of hyperaldosteronism when symptoms are present include:HypokalaemiaMetabolic alkalosisHypertensionNormal or slightly raised sodium levels
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 24
Incorrect
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A 29-year-old female with a swollen red finger presents to your clinic and you suspect that the underlying process is of acute inflammation. You request for some bloods investigations.Which statement about histamine as a chemical mediator of the acute inflammatory response is TRUE?
Your Answer: Neutrophils are the primary source
Correct Answer: It increases vascular permeability
Explanation:Histamine increases vascular permeability in the acute inflammatory response.Histamine causes vasodilation.It is released from Mast cells and basophils, eosinophils and platelets. Mast cells and basophils are its primary source Nitric oxide (not histamine) is a major factor in endotoxic shock
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 25
Incorrect
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Compliance is greater in all but which one of the following:
Your Answer: The lung volume at functional residual capacity
Correct Answer: Pulmonary oedema
Explanation:Compliance changes at different lung volumes. Initially at lower lung volumes the compliance of the lung is poor and greater pressure change is required to cause a change in volume. This occurs if the lungs become collapsed for a period of time. At functional residual capacity (FRC) compliance is optimal since the elastic recoil of the lung tending towards collapse is balanced by the tendency of the chest wall to spring outwards. At higher lung volumes the compliance of the lung again becomes less as the lung becomes stiffer. At all volumes, the base of the lung has a greater compliance than the apex. Patients with emphysema have increased compliance. Compliance is affected by a person’s age, sex and height.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 26
Incorrect
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Which of the following is a contraindication for aspirin?
Your Answer: Thrombophilia
Correct Answer: Children under 16 years
Explanation:Aspirin contraindications include: hypersensitivity to NSAIDs; asthma, rhinitis, and nasal polyps; and usage in children or teens.There is little evidence of allergic cross-reactivity for salicylates. However, due to similarities in chemical structure and/or pharmacologic activities, the possibility of cross-sensitivity cannot be completely ruled out.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 27
Incorrect
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A 45-year-old man had a painless superficial inguinal lymphadenopathy. It was later found to be malignant. Which of the following parts of the body is most likely the origin of this cancerous lymph node?
Your Answer: Sigmoid colon
Correct Answer: Anal canal
Explanation:A cancer of the anal canal below the pectinate line would spread to the superficial inguinal lymph nodes. Anal cancer often spreads through lymphatic drainage to the internal iliac lymph nodes in lesions above the pectinate line and to the superficial inguinal lymph nodes in lesions below the pectinate line.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 28
Incorrect
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Which of the following decreases activation of vitamin D:
Your Answer: Hyperparathyroidism
Correct Answer: Chronic renal failure
Explanation:Calcium deficiency (low Ca2+ diet or hypocalcemia) activates 1-alpha-hydroxylase in the cells of the renal proximal tubule which catalyses the conversion of vitamin D to its active form, 1,25-dihydroxycholecalciferol. Increased parathyroid hormone (PTH) and hypophosphatemia also stimulate the enzyme. Chronic renal failure is associated with a constellation of bone diseases, including osteomalacia caused by failure of the diseased renal tissue to produce the active form of vitamin D.
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This question is part of the following fields:
- Endocrine
- Physiology
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Question 29
Incorrect
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By which of the following is mean arterial pressure (MAP) primarily determined?
Your Answer: Stroke volume and heart rate
Correct Answer: Total peripheral resistance and cardiac output
Explanation:Mean arterial pressure (MAP) = Cardiac output (CO) x Total peripheral resistance (TPR). Cardiac output is dependent on the central venous pressure (CVP). CVP, in turn, is highly dependent on the blood volume. Any alterations of any of these variables will likely change MAP.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 30
Incorrect
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Which of the following is an action of glucagon:
Your Answer: Inhibits gluconeogenesis
Correct Answer: Stimulates glycogenolysis
Explanation:Glucagon is a peptide hormone that is produced and secreted by alpha cells of the islets of Langerhans, which are located in the endocrine portion of the pancreas. The main physiological role of glucagon is to stimulate hepatic glucose output, thereby leading to increases in glycaemia. It provides the major counter-regulatory mechanism to insulin in maintaining glucose homeostasis.Hypoglycaemia is the principal stimulus for the secretion of glucagon but may also be used as an antidote in beta-blocker overdose and in anaphylaxis in patients on beta-blockers that fail to respond to adrenaline. Glucagon then causes:GlycogenolysisGluconeogenesisLipolysis in adipose tissueThe secretion of glucagon is also stimulated by:AdrenalineCholecystokininArginineAlanineAcetylcholineThe secretion of glucagon is inhibited by:InsulinSomatostatinIncreased free fatty acidsIncreased urea productionGlycolysis is the metabolic pathway that converts glucose into pyruvate. The free energy released by this process is used to form ATP and NADH. Glycolysis is inhibited by glucagon, and glycolysis and gluconeogenesis are reciprocally regulated so that when one cell pathway is activated, the other is inactive and vice versa.Glucagon has a minor effect of enhancing lipolysis in adipose tissue. Lipolysis is the breakdown of lipids and involves the hydrolysis of triglycerides into glycerol and free fatty acids. It makes fatty acids available for oxidation.
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This question is part of the following fields:
- Endocrine
- Pharmacology
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SESSION STATS - PERFORMANCE PER SPECIALTY
