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  • Question 1 - Regarding the management of diabetic ketoacidosis (DKA), insulin should initially be given: ...

    Incorrect

    • Regarding the management of diabetic ketoacidosis (DKA), insulin should initially be given:

      Your Answer: At a concentration of 0.1 units/mL at a fixed rate of 1 units/kg/hour

      Correct Answer: At a concentration of 1 unit/mL at a fixed rate of 0.1 units/kg/hour

      Explanation:

      An intravenous insulin infusion should be started at a concentration of 1 unit/mL, at a fixed rate of 0.1 units/kg/hour. Established subcutaneous long-acting insulin therapy should be continued concomitantly. Blood ketone and blood glucose concentrations should be checked hourly and the insulin infusion rate adjusted accordingly. Blood ketone concentration should fall by at least 0.5 mmol/litre/hour and blood glucose concentration should fall by at least 3 mmol/litre/hour.

    • This question is part of the following fields:

      • Endocrine
      • Pharmacology
      215.1
      Seconds

  • Question 2 - What is the pathophysiology of Cushing's syndrome: ...

    Correct

    • What is the pathophysiology of Cushing's syndrome:

      Your Answer: Glucocorticoid excess

      Explanation:

      Cushing’s syndrome is the name given to the clinical symptoms and signs induced by chronic glucocorticoid excess.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      8.3
      Seconds

  • Question 3 - Which of the following is NOT a mineralocorticoid effect of corticosteroids: ...

    Incorrect

    • Which of the following is NOT a mineralocorticoid effect of corticosteroids:

      Your Answer: Oedema

      Correct Answer: Hyperglycaemia

      Explanation:

      Mineralocorticoid side effects include:hypertensionsodium retentionwater retention and oedemapotassium losscalcium loss
      Glucocorticoid side effects include:weight gainhyperglycaemia and diabetesosteoporosis and osteoporotic fracturesmuscle wasting (proximal myopathy)peptic ulceration and perforationpsychiatric reactions

    • This question is part of the following fields:

      • Endocrine
      • Pharmacology
      21.5
      Seconds

  • Question 4 - Regarding hypernatraemia, which of the following statements is INCORRECT: ...

    Incorrect

    • Regarding hypernatraemia, which of the following statements is INCORRECT:

      Your Answer: Diabetes insipidus causes hypernatraemia secondary to a pure water deficit.

      Correct Answer: In acute severe hypernatraemia, seizures and intracranial vascular haemorrhage can occur as a result of brain cell lysis.

      Explanation:

      Acute severe hypernatraemia is a medical emergency and requires inpatient management in a high dependency setting. Seizures and intracranial vascular haemorrhage as a result of brain cell crenation can occur. The cause is most commonly excessive water loss and the key aspect of treatment is aggressive fluid replacement (typically with normal saline as this is relatively hypotonic). If urine osmolality is low, diabetes insipidus (DI )should be considered and a trial of synthetic ADH given. In patients with known DI, it is essential to ensure synthetic ADH is given parenterally and that close fluid balance is observed.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      43.5
      Seconds

  • Question 5 - Which of the following acts to inhibit antidiuretic hormone (ADH) release from the...

    Incorrect

    • Which of the following acts to inhibit antidiuretic hormone (ADH) release from the posterior pituitary:

      Your Answer: Aldosterone

      Correct Answer: Atrial natriuretic peptide

      Explanation:

      ADH release is inhibited by low plasma osmolality, alcohol, caffeine, glucocorticoids and atrial natriuretic peptide (ANP).

      ADH release is stimulated primarily by raised plasma osmolality detected by osmoreceptors in the anterior hypothalamus. Other factors that increase ADH release include: extracellular fluid volume depletion, angiotensin II, nausea, pain, stress, exercise, emotion, hypoglycaemia.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      10
      Seconds

  • Question 6 - Which of the following statements is correct regarding hyponatraemia? ...

    Correct

    • Which of the following statements is correct regarding hyponatraemia?

      Your Answer: Correction of serum sodium that is too rapid can precipitate central pontine myelinolysis.

      Explanation:

      Hyponatraemia refers to a serum sodium concentration < 135 mmol/L.
      It is safer to quickly correct acute hyponatremia than chronic hyponatremia but correction should not be too fast, especially in chronic hyponatraemia, because of the risk of central pontine myelinolysis. Hyponatraemia is usually associated with a low plasma osmolality.
      Under normal circumstances, if serum osmolality is low, then urine osmolality should also be low because the kidneys should be trying to retain solute.
      In SIADH, excess ADH causes water retention, but not the retention of solute. Therefore, urine that is concentrated and relatively high in sodium is produced, even though the serum sodium is low (urine osmolality > 100 mosmol/kg).

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      9.1
      Seconds

  • Question 7 - Which of the following statements regarding the pituitary gland is CORRECT: ...

    Incorrect

    • Which of the following statements regarding the pituitary gland is CORRECT:

      Your Answer:

      Correct Answer: Cortisol inhibits release of adrenocorticotropic hormone (ACTH) from the anterior pituitary.

      Explanation:

      Anterior pituitary hormones are released under the control of hypothalamic releasing or inhibiting hormones originating from small neurons with their cell bodies in the hypothalamus and released into the blood at the median eminence. These hypothalamic hormones are transported directly to the anterior pituitary via hypophyseal portal vessels. The anterior pituitary hormones (and the hormones released by their target organs) inhibit further release of hypothalamic and anterior pituitary hormones by negative feedback mechanisms e.g. cortisol inhibits the release of ACTH. Prolactin release from the anterior pituitary is inhibited by dopamine.The posterior pituitary is really a direct extension of the hypothalamus. Oxytocin and ADH are manufactured in the cell bodies of large neurons in the hypothalamus and are transported down the axons of these cells to their terminals on capillaries originating from the inferior hypophyseal artery within the posterior pituitary gland. ADH release is controlled by negative feedback mechanisms based on plasma osmolality and blood volume, oxytocin however is involved in positive feedback mechanisms.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 8 - The pathophysiology of Addison's disease is as follows: ...

    Incorrect

    • The pathophysiology of Addison's disease is as follows:

      Your Answer:

      Correct Answer: Adrenocortical insufficiency

      Explanation:

      Primary adrenal insufficiency, also known as Addison’s disease, occurs when the adrenal glands cannot produce an adequate amount of hormones despite a normal or increased corticotropin (ACTH) level.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 9 - Which of the following is NOT a typical effect caused by adrenaline: ...

    Incorrect

    • Which of the following is NOT a typical effect caused by adrenaline:

      Your Answer:

      Correct Answer: Bronchoconstriction

      Explanation:

      Actions of adrenaline:
      Cardiovascular system
      – Increased rate and force of cardiac contraction
      – Vasoconstriction of vessels in skin, mucous membranes and splanchnic bed
      – Vasodilation of skeletal muscle vessels
      – Increased cardiac output and blood pressure
      Respiratory system
      – Bronchodilation
      – Increased ventilation rate
      Gastrointestinal system
      – Smooth muscle relaxation
      – Contraction of sphincters
      – Metabolism
      – Decreased insulin release
      – Increased glucagon release
      – Increased thermogenesis
      – Increased glycolysis
      – Increased lipolysis
      Eye
      – Pupillary dilation

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 10 - All of the following are physiological effects of thyroid hormones except: ...

    Incorrect

    • All of the following are physiological effects of thyroid hormones except:

      Your Answer:

      Correct Answer: Increased glycogenesis

      Explanation:

      Thyroid hormones have multiple physiological effects on the body. These include:
      1. Heat production (thermogenesis)
      2. Increased basal metabolic rate
      3. Metabolic effects:
      (a) Increase in protein turnover (both synthesis and degradation are increased, although overall effect is catabolic)
      (b) Increase in lipolysis
      (c)Increase in glycogenolysis and gluconeogenesis
      4. Enhanced catecholamine effect – Increase in heart rate, stroke volume and thus cardiac output
      5. Important role in growth and development

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 11 - Which of the following is the most common cause of hyperthyroidism: ...

    Incorrect

    • Which of the following is the most common cause of hyperthyroidism:

      Your Answer:

      Correct Answer: Graves disease

      Explanation:

      Graves disease is the most common cause of hyperthyroidism. It is an autoimmune disease in which autoantibodies against TSH receptors are produced. These antibodies bind to and stimulate these TSH receptors leading to an excess production of thyroid hormones. Therefore, the signs and symptoms of Graves disease are the same as those of hyperthyroidism, reflecting the actions of increased circulating levels of thyroid hormones: increased heat production, weight loss, increased 02 consumption and cardiac output and exophthalmos (bulging eyes, not drooping eyelids). TSH levels will be decreased (not increased) as a result of the negative feedback effect of increased T3 levels on the anterior pituitary.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 12 - Which of the following hormones is dysfunctional in diabetes insipidus: ...

    Incorrect

    • Which of the following hormones is dysfunctional in diabetes insipidus:

      Your Answer:

      Correct Answer: Antidiuretic hormone

      Explanation:

      Diabetes insipidus (DI) may result from a deficiency of ADH secretion (cranial DI) or from an inappropriate renal response to ADH (nephrogenic DI). As a result, fluid reabsorption at the kidneys is impaired, resulting in large amounts of hypotonic, dilute urine being passed with a profound unquenchable polydipsia.
      The biochemical hallmarks of DI are:
      High plasma osmolality (> 295 mOsm/kg)
      Low urine osmolality (< 300 mOsm/kg)
      Hypernatraemia (> 145 mmol/L)
      High urine volume

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 13 - Which of the following is an action of glucagon: ...

    Incorrect

    • Which of the following is an action of glucagon:

      Your Answer:

      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:
      Glycogenolysis
      Gluconeogenesis
      Lipolysis in adipose tissue
      The secretion of glucagon is also stimulated by:
      Adrenaline
      Cholecystokinin
      Arginine
      Alanine
      Acetylcholine
      The secretion of glucagon is inhibited by:
      Insulin
      Somatostatin
      Increased free fatty acids
      Increased urea production

      Glycolysis 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.

    • This question is part of the following fields:

      • Endocrine
      • Pharmacology
      0
      Seconds

  • Question 14 - Which of the following is NOT one of insulin's actions: ...

    Incorrect

    • Which of the following is NOT one of insulin's actions:

      Your Answer:

      Correct Answer: Increased gluconeogenesis

      Explanation:

      Insulin has a number of effects on glucose metabolism, including:
      Inhibition of glycogenolysis and gluconeogenesis
      Increased glucose transport into fat and muscle
      Increased glycolysis in fat and muscle
      Stimulation of glycogen synthesis
      By inhibiting gluconeogenesis, insulin maintains the availability of amino acids as substrates for protein synthesis. Thus, insulin supports protein synthesis through direct and indirect mechanisms.

    • This question is part of the following fields:

      • Endocrine
      • Pharmacology
      0
      Seconds

  • Question 15 - Which of the following has the most potent glucocorticoid effect: ...

    Incorrect

    • Which of the following has the most potent glucocorticoid effect:

      Your Answer:

      Correct Answer: Dexamethasone

      Explanation:

      Dexamethasone and betamethasone have the most potent glucocorticoid (anti-inflammatory) effect.

    • This question is part of the following fields:

      • Endocrine
      • Pharmacology
      0
      Seconds

  • Question 16 - Which of the following statements is correct with regards to insulin receptors? ...

    Incorrect

    • Which of the following statements is correct with regards to insulin receptors?

      Your Answer:

      Correct Answer: Insulin has its intracellular effects via activation of tyrosine kinase.

      Explanation:

      Most cells have insulin receptors present on them which can be sequestered into the cell to inactivate them. These receptors consist of two extracellular alpha subunits which contain the insulin-binding site and two transmembrane beta subunits. Because insulin is a polypeptide hormone, it must act via cell surface receptors as it is unable to readily cross the cell membrane. On binding to the receptor, the beta subunit of insulin autophosphorylation, which activates tyrosine kinase. As a result, there is an intracellular cascade of phosphorylation, causing a translocation of the glucose transporter GLUT4 and GLUT-1 to the plasma membrane of the affected cell. This facilitates glucose entry.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 17 - Which of the following is a common adverse effect of glucagon: ...

    Incorrect

    • Which of the following is a common adverse effect of glucagon:

      Your Answer:

      Correct Answer: Nausea

      Explanation:

      Adverse effects include:
      Common: Nausea
      Uncommon: Vomiting
      Rare: Abdominal pain, hypertension, hypotension, tachycardia

    • This question is part of the following fields:

      • Endocrine
      • Pharmacology
      0
      Seconds

  • Question 18 - Which of the following is a physiological function that is mediated by a...

    Incorrect

    • Which of the following is a physiological function that is mediated by a hormone released by the posterior pituitary:

      Your Answer:

      Correct Answer: Water retention

      Explanation:

      Antidiuretic hormone (ADH), released by the posterior pituitary, acts on the kidneys to increase water permeability in the distal nephron allowing greater water reabsorption and concentration of urine. Prolactin, from the anterior pituitary, is responsible for milk production. The thyroid hormones, from the thyroid gland, are responsible for an increase in basal metabolic rate (stimulated by TSH from the anterior pituitary). FSH/LH, from the anterior pituitary, are responsible for maturation of egg and sperm. Calcitonin, from the thyroid gland, is responsible for decreasing calcium levels.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 19 - Dehydration causes a significant increase in the amount of this hormone? ...

    Incorrect

    • Dehydration causes a significant increase in the amount of this hormone?

      Your Answer:

      Correct Answer: Antidiuretic hormone

      Explanation:

      Antidiuretic hormone induces the kidneys to release less water, resulting in reduced urine production.

      In the case of dehydration, ADH levels rise, resulting in a considerable decrease in urine output as well as an increase in plasma protein, blood Hct, and serum osmolality.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 20 - Which of the following factors does NOT decrease glucagon secretion: ...

    Incorrect

    • Which of the following factors does NOT decrease glucagon secretion:

      Your Answer:

      Correct Answer: Catecholamines

      Explanation:

      Factors that increase glucagon secretion:
      ↓ Blood glucose
      ↑ Amino acids
      Cholecystokinin
      Catecholamines
      Acetylcholine

      Factors that decrease glucagon secretion:
      ↑ Blood glucose
      Insulin
      Somatostatin
      Fatty acids, ketoacids

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 21 - Antidiuretic hormone (ADH) has which of the following effects: ...

    Incorrect

    • Antidiuretic hormone (ADH) has which of the following effects:

      Your Answer:

      Correct Answer: Increases urine osmolality

      Explanation:

      ADH binds V2 receptors on renal principal cells in the late distal tubule and collecting ducts, raising cAMP levels and causing intracellular vesicles to fuse with the apical membrane. In their membrane these vesicles have water channels called aquaporins, which increase the water permeability allowing greater water reabsorption and concentration of urine. ADH also binds to V1 receptor receptors on vascular smooth muscle, causing vasoconstriction and enhancing the effect of aldosterone on sodium reabsorption in the distal tubule. ADH release is stimulated primarily by raised plasma osmolality detected by osmoreceptors in the anterior hypothalamus. Other factors that increase ADH release include: extracellular fluid volume depletion, angiotensin II, nausea, pain, stress, exercise, emotion, hypoglycaemia. ADH release is inhibited by low plasma osmolality, alcohol, caffeine, glucocorticoids and atrial natriuretic peptide (ANP). ADH deficiency (or an inadequate response to ADH) results in diabetes insipidus. Excess levels of ADH results in syndrome of inappropriate ADH secretion (SIADH).

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 22 - Monoamine oxidase is primarily involved in the degradation of which of the following:...

    Incorrect

    • Monoamine oxidase is primarily involved in the degradation of which of the following:

      Your Answer:

      Correct Answer: Noradrenaline

      Explanation:

      Catecholamines are broken down extracellularly and in the liver by catechol-O-methyltransferase (COMT) and intracellularly by monoamine oxidase (MAO).

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 23 - Which of the following is a primary action of aldosterone: ...

    Incorrect

    • Which of the following is a primary action of aldosterone:

      Your Answer:

      Correct Answer: Renal sodium reabsorption

      Explanation:

      Aldosterone acts mainly at the renal distal convoluted tubule (DCT) to cause sodium retention and potassium loss. It increases the synthesis of transport mechanisms in the distal nephron including the Na+pump, Na+/H+symporter, and Na+and K+channels in principal cells, and H+ATPase in intercalated cells. Na+(and thus water) reabsorption and K+and H+secretion are thereby enhanced.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 24 - When treating diabetic ketoacidosis (DKA), glucose should be given together with insulin as...

    Incorrect

    • When treating diabetic ketoacidosis (DKA), glucose should be given together with insulin as soon as the blood glucose concentration falls below 14 mmol/L in the form of:

      Your Answer:

      Correct Answer: 10% glucose intravenous infusion at a rate of 125 mL/hour

      Explanation:

      In addition to the sodium chloride 0.9 percent infusion, glucose 10% should be given intravenously (into a large vein with a large-gauge needle) at a rate of 125 mL/hour once blood glucose concentration falls below 14 mmol/litre.

    • This question is part of the following fields:

      • Endocrine
      • Pharmacology
      0
      Seconds

  • Question 25 - A 32 year old woman presents with episodes of flushing, headaches and palpitations....

    Incorrect

    • A 32 year old woman presents with episodes of flushing, headaches and palpitations. On examination her blood pressure is significantly elevated. Which of the following is the most likely diagnosis:

      Your Answer:

      Correct Answer: Pheochromocytoma

      Explanation:

      Phaeochromocytomas are catecholamine-secreting tumours which occur in about 0.1% of patients with hypertension. In about 90% of cases they arise from the adrenal medulla. The remaining 10%, which arise from extra-adrenal chromaffin tissue, are termed paragangliomas. Common presenting symptoms include one or more of headache, sweating, pallor and palpitations. Less commonly, patients describe anxiety, panic attacks and pyrexia. Hypertension, whether sustained or episodic, is present in at least 90% of patients. Left untreated phaeochromocytoma can occasionally lead to hypertensive crisis, encephalopathy, hyperglycaemia, pulmonary oedema, cardiac arrhythmias, or even death.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 26 - What is the pathophysiology of a phaeochromocytoma: ...

    Incorrect

    • What is the pathophysiology of a phaeochromocytoma:

      Your Answer:

      Correct Answer: Catecholamine-secreting tumour

      Explanation:

      Phaeochromocytomas are catecholamine-secreting tumours which occur in about 0.1% of patients with hypertension. In about 90% of cases they arise from the adrenal medulla. The remaining 10%, which arise from extra-adrenal chromaffin tissue, are termed paragangliomas. Common presenting symptoms include one or more of headache, sweating, pallor and palpitations. Less commonly, patients describe anxiety, panic attacks and pyrexia. Hypertension, whether sustained or episodic, is present in at least 90% of patients. Left untreated phaeochromocytoma can occasionally lead to hypertensive crisis, encephalopathy, hyperglycaemia, pulmonary oedema, cardiac arrhythmias, or even death.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 27 - A 43 year old lady who has a previous medical history of hyperthyroidism...

    Incorrect

    • A 43 year old lady who has a previous medical history of hyperthyroidism presents to the emergency room with sweating, palpitations and agitation. On examination, she is tachycardic, hypertensive and hyperpyrexic. She recently had a stomach bug and has not been able to take her medication regularly. The best medication to immediately treat her symptoms is which of the following?

      Your Answer:

      Correct Answer: Propranolol

      Explanation:

      There is a high suspicion of a thyroid crisis in this patient and emergent treatment should be initiated even before the results of TFT’s have returned. Antiadrenergic drugs like IV propranolol should be administered immediately to minimise sympathomimetic symptoms. Antithyroid medications like propylthiouracil or carbimazole should be administered to block further synthesis of thyroid hormones. After thionamide therapy has been started to prevent stimulation of new hormone synthesis, there should then be delayed administration of oral iodine solution. Hydrocortisone administration is also recommended as it treats possible relative adrenal insufficiency while also decreases peripheral conversion of T4 to T3.

    • This question is part of the following fields:

      • Endocrine
      • Pharmacology
      0
      Seconds

  • Question 28 - Which of the following is NOT a typical clinical feature of osteomalacia: ...

    Incorrect

    • Which of the following is NOT a typical clinical feature of osteomalacia:

      Your Answer:

      Correct Answer: Hypercalcaemia

      Explanation:

      Features of osteomalacia include:
      Bone pain (particularly bone, pelvis, ribs)
      Neuromuscular dysfunction (particularly in the gluteal muscles, leading to waddling gait
      Pseudofractures on x-ray (looser zones)
      Elevated alkaline phosphatase, hypocalcaemia and low phosphate due to secondary hyperparathyroidism

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 29 - A 70 year old man who has a previous history of small cell...

    Incorrect

    • A 70 year old man who has a previous history of small cell lung cancer was found to have severe hyponatraemia on a recent blood test and he is sent to the emergency room. In the nephron, where is the likely cause of this abnormality?

      Your Answer:

      Correct Answer: Distal nephron

      Explanation:

      In the cancer patient, hyponatremia is usually caused by the syndrome of inappropriate antidiuretic hormone (SIADH). This develops more frequently with small cell lung cancer (SCLC) than with other malignancies. The pathogenesis of this is as a result of the process whereby ADH binds V2 receptors on renal principal cells in the late distal tubule and collecting ducts, resulting in elevation of cAMP levels. Increased cAMP levels cause fusion of intracellular vesicles with the apical membrane. There are water channels called aquaporins in their membranes of these vesicles, and these increase the water permeability, thus facilitating increased water reabsorption and urine concentration. Thus, by increasing water retention, ADH causes blood to be diluted, which then decreases the concentration of solutes like sodium.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 30 - Which of the following causes type 1 diabetes mellitus? ...

    Incorrect

    • Which of the following causes type 1 diabetes mellitus?

      Your Answer:

      Correct Answer: Autoimmune destruction of beta-cells results in insulin deficiency

      Explanation:

      Type 1 diabetes mellitus results from autoimmune destruction of the insulin-producing beta cells in the islets of Langerhans. This process occurs in genetically susceptible subjects, is probably triggered by one or more environmental agents, and usually progresses over many months or years during which the subject is asymptomatic and euglycemic.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 31 - Which of the following is NOT a typical clinical feature of diabetic ketoacidosis:...

    Incorrect

    • Which of the following is NOT a typical clinical feature of diabetic ketoacidosis:

      Your Answer:

      Correct Answer: Cheyne–Stokes respiration

      Explanation:

      Clinical features of DKA:
      Symptoms: Polyuria, polydipsia, thirst, lethargy, weight loss, nausea, vomiting, anorexia, abdominal pain, dehydration, headache, altered mental state
      Signs: Dry mucous membranes, ketotic breath, tachycardia, hypotension, Kussmaul breathing, focal signs of precipitant e.g. infection

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 32 - Which of the following corticosteroids has the most potent mineralocorticoid effect: ...

    Incorrect

    • Which of the following corticosteroids has the most potent mineralocorticoid effect:

      Your Answer:

      Correct Answer: Fludrocortisone

      Explanation:

      Fludrocortisone has the most potent mineralocorticosteroid activity, making it ideal for mineralocorticoid replacement in adrenal insufficiency.

    • This question is part of the following fields:

      • Endocrine
      • Pharmacology
      0
      Seconds

  • Question 33 - Which of the following is NOT a typical effect of cortisol: ...

    Incorrect

    • Which of the following is NOT a typical effect of cortisol:

      Your Answer:

      Correct Answer: Decreased protein catabolism

      Explanation:

      Cortisol is a steroid hormone produced in the zona fasciculata of the adrenal cortex. It is released in response to stress and low blood glucose concentrations.
      Cortisol acts to: raise plasma glucose by stimulating glycolysis and gluconeogenesis in the liver and inhibiting peripheral glucose uptake into storage tissues, increase protein breakdown in skeletal muscle, skin and bone to release amino acids, increase lipolysis from adipose tissues to release fatty acidsand at higher levels and mimic the actions of aldosterone on the kidney to retain Na+ and water and lose K+ ionssuppress the action of immune cells

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 34 - A 28 year old man presents with abdominal pain and constipation, and bloods...

    Incorrect

    • A 28 year old man presents with abdominal pain and constipation, and bloods show hypocalcaemia. Which of the following hormones is increased as a result of hypocalcaemia?

      Your Answer:

      Correct Answer: Parathyroid hormone

      Explanation:

      Parathyroid hormone (PTH), also called parathormone or parathyrin, is a peptide hormone that is secreted by the parathyroid glands, which lie immediately behind the thyroid gland. In particular, this hormone is made by chief cells. It regulates the serum calcium concentration through its effects on bone, kidney, and intestine. This hormone is primarily released in response to decreasing plasma Ca2+ concentration and it serves to increase plasma calcium levels and decrease plasma phosphate levels.
      PTH activates Ca2+entry channels in the apical membrane and the Ca2+ATPase pump in the basolateral membrane and as a result, increases calcium reabsorption in the distal tubule of the nephron. It inhibits reabsorption of phosphate and this increases its excretion by in the proximal tubule of the nephron.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 35 - When treating diabetic ketoacidosis (DKA), which of the following should be given if...

    Incorrect

    • When treating diabetic ketoacidosis (DKA), which of the following should be given if the systolic blood pressure is initially less than 90 mmHg:

      Your Answer:

      Correct Answer: 500 mL sodium chloride 0.9% intravenous infusion over 10 - 15 minutes

      Explanation:

      If SBP is less than 90 mmHg , 500 mL sodium chloride 0.9 percent should be administered intravenously over 10–15 minutes, and repeated if SBP remains less than 90 mmHg. When SBP is greater than 90 mmHg, sodium chloride infusion must be maintained at a rate that replaces the deficit.

    • This question is part of the following fields:

      • Endocrine
      • Pharmacology
      0
      Seconds

  • Question 36 - Adrenocorticotropic hormone release from the anterior pituitary is stimulated by which of the...

    Incorrect

    • Adrenocorticotropic hormone release from the anterior pituitary is stimulated by which of the following:

      Your Answer:

      Correct Answer: Corticotropin-releasing hormone

      Explanation:

      ACTH secretion is stimulated by corticotropin-releasing hormone (CRH) from the hypothalamus.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 37 - Parathyroid hormone is released by which of the following: ...

    Incorrect

    • Parathyroid hormone is released by which of the following:

      Your Answer:

      Correct Answer: Chief cells of the parathyroid gland

      Explanation:

      Parathyroid hormone (PTH) is a peptide hormone synthesised by the chief cells of the parathyroid glands, located immediately behind the thyroid gland. PTH is primarily released in response to decreasing plasma [Ca2+] concentration. PTH acts to increase plasma calcium levels and decrease plasma phosphate levels.
      Parathyroid hormone (PTH) acts to increase calcium reabsorption in the distal tubule of the nephron (by activating Ca2+entry channels in the apical membrane and the Ca2+ATPase pump in the basolateral membrane) and increase phosphate excretion by inhibiting reabsorption in the proximal tubule of the nephron.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 38 - What is the effect of activated vitamin D on the renal handling of...

    Incorrect

    • What is the effect of activated vitamin D on the renal handling of calcium:

      Your Answer:

      Correct Answer: Increases calcium reabsorption in the distal tubule

      Explanation:

      Activated vitamin D acts to:
      GUT:increase calcium and phosphate absorption in the small intestine (the main action)
      KIDNEYS:increase renal calcium reabsorption (in the distal tubule via activation of a basolateral Ca2+ATPase pump), increase renal phosphate reabsorption, inhibit 1-alpha-hydroxylase activity in the kidneys (negative feedback)
      PARATHYROID GLANDS:inhibit PTH secretion from the parathyroid glands

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 39 - Alpha cells of the endocrine pancreas produce which of the following hormones: ...

    Incorrect

    • Alpha cells of the endocrine pancreas produce which of the following hormones:

      Your Answer:

      Correct Answer: Glucagon

      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:
      Glycogenolysis
      Gluconeogenesis
      Lipolysis in adipose tissue
      The secretion of glucagon is also stimulated by:
      Adrenaline
      Cholecystokinin
      Arginine
      Alanine
      Acetylcholine
      The secretion of glucagon is inhibited by:
      Insulin
      Somatostatin
      Increased free fatty acids
      Increased urea production

      Glycolysis 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.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 40 - Insulin is produced by which of the following pancreatic cells: ...

    Incorrect

    • Insulin is produced by which of the following pancreatic cells:

      Your Answer:

      Correct Answer: β cells

      Explanation:

      Insulin is produced by beta cells, located centrally within the islets of Langerhans, in the endocrine tissues of the pancreas. Insulin is a polypeptide hormone consisting of two short chains (A and B) linked by disulphide bonds. Proinsulin is synthesised as a single-chain peptide. Within storage granules, a connecting peptide (C peptide) is removed by proteases to yield insulin. Insulin release is stimulated initially during eating by the parasympathetic nervous system and gut hormones such as secretin, but most output is driven by the rise in plasma glucose concentration that occurs after a meal. The effects of insulin are mediated by the receptor tyrosine kinase.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 41 - Beta cells of the endocrine pancreas produce which of the following hormones: ...

    Incorrect

    • Beta cells of the endocrine pancreas produce which of the following hormones:

      Your Answer:

      Correct Answer: Insulin

      Explanation:

      Insulin is produced by beta cells, located centrally within the islets of Langerhans, in the endocrine tissues of the pancreas. Insulin is a polypeptide hormone consisting of two short chains (A and B) linked by disulphide bonds. Proinsulin is synthesised as a single-chain peptide. Within storage granules, a connecting peptide (C peptide) is removed by proteases to yield insulin. Insulin release is stimulated initially during eating by the parasympathetic nervous system and gut hormones such as secretin, but most output is driven by the rise in plasma glucose concentration that occurs after a meal. The effects of insulin are mediated by the receptor tyrosine kinase.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 42 - Antidiuretic hormone (ADH) is synthesised by which of the following: ...

    Incorrect

    • Antidiuretic hormone (ADH) is synthesised by which of the following:

      Your Answer:

      Correct Answer: Hypothalamus

      Explanation:

      Antidiuretic hormone is synthesised in the hypothalamus and transported to the posterior pituitary within nerve fibres where it is stored in secretory granules. ADH binds V2 receptors on renal principal cells in the late distal tubule and collecting ducts, raising cAMP levels and causing intracellular vesicles to fuse with the apical membrane. In their membrane these vesicles have water channels called aquaporins, which increase the water permeability allowing greater water reabsorption and concentration of urine. Excess levels of ADH results in syndrome of inappropriate ADH secretion (SIADH) characterised by hyponatremia with concomitant hypo-osmolality and high urine osmolality.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 43 - Glucagon may be used as an antidote for overdose with which of the...

    Incorrect

    • Glucagon may be used as an antidote for overdose with which of the following:

      Your Answer:

      Correct Answer: Beta blockers

      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:
      Glycogenolysis
      Gluconeogenesis
      Lipolysis in adipose tissue
      The secretion of glucagon is also stimulated by:
      Adrenaline
      Cholecystokinin
      Arginine
      Alanine
      Acetylcholine
      The secretion of glucagon is inhibited by:
      Insulin
      Somatostatin
      Increased free fatty acids
      Increased urea production

      Glycolysis 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.

    • This question is part of the following fields:

      • Endocrine
      • Pharmacology
      0
      Seconds

  • Question 44 - Which of the following factors decreases insulin secretion: ...

    Incorrect

    • Which of the following factors decreases insulin secretion:

      Your Answer:

      Correct Answer: Catecholamines

      Explanation:

      Factors that increase insulin secretion:
      ↑ Blood glucose
      ↑ Amino acids
      ↑ Fatty acids
      Glucagon
      Secretin
      Acetylcholine

      Factors that decrease insulin secretion:
      ↓ Blood glucose
      Somatostatin
      Catecholamines

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 45 - Glucagon is contraindicated in which of the following: ...

    Incorrect

    • Glucagon is contraindicated in which of the following:

      Your Answer:

      Correct Answer: Pheochromocytoma

      Explanation:

      Glucagon is contraindicated in pheochromocytoma.

    • This question is part of the following fields:

      • Endocrine
      • Pharmacology
      0
      Seconds

  • Question 46 - Glucagon is secreted by which of the following pancreatic cell types: ...

    Incorrect

    • Glucagon is secreted by which of the following pancreatic cell types:

      Your Answer:

      Correct Answer: α cells

      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:
      Glycogenolysis
      Gluconeogenesis
      Lipolysis in adipose tissue
      The secretion of glucagon is also stimulated by:
      Adrenaline
      Cholecystokinin
      Arginine
      Alanine
      Acetylcholine
      The secretion of glucagon is inhibited by:
      Insulin
      Somatostatin
      Increased free fatty acids
      Increased urea production

      Glycolysis 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.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 47 - All of the following are actions of insulin except: ...

    Incorrect

    • All of the following are actions of insulin except:

      Your Answer:

      Correct Answer: Increased gluconeogenesis

      Explanation:

      Major Actions of Insulin:
      ↑ Glucose uptake into cells
      ↑ Glycogenesis
      ↓ Glycogenolysis
      ↓ Gluconeogenesis
      ↑ Protein synthesis
      ↓ Protein degradation
      ↑ Fat deposition
      ↓ Lipolysis
      ↓ Ketoacid production
      ↑ K+ uptake into cells

      Major Actions of Glucagon:
      ↓ Glycogenesis
      ↑ Glycogenolysis
      ↑ Gluconeogenesis
      ↓ Fatty acid synthesis
      ↑ Lipolysis
      ↑ Ketoacid production

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 48 - A patient is sent in to ED by her GP with hyponatraemia and...

    Incorrect

    • A patient is sent in to ED by her GP with hyponatraemia and hyperkalaemia. There is most likely to be a deficiency in which of the following hormones:

      Your Answer:

      Correct Answer: Aldosterone

      Explanation:

      A deficiency of aldosterone, as seen in adrenal insufficiency, can result in hyponatraemia and hyperkalaemia.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 49 - Which of the following is a primary action of calcitonin: ...

    Incorrect

    • Which of the following is a primary action of calcitonin:

      Your Answer:

      Correct Answer: Decreased bone resorption through inhibition of osteoclast activity

      Explanation:

      Calcitonin is a 32 amino acid polypeptide that is primarily synthesised and released by the parafollicular cells (C-cells) of the thyroid gland in response to rising or high levels of plasma Ca2+ions. Its primary role is to reduce the plasma calcium concentration, therefore opposing the effects of parathyroid hormone.
      Secretion of calcitonin is stimulated by:
      – Increased plasma calcium concentration
      – Gastrin
      – Pentagastrin
      – The main actions of calcitonin are:
      – Inhibition of osteoclastic activity (decreasing calcium and phosphate resorption from bone)
      – Stimulation of osteoblastic activity
      – Decreases renal calcium reabsorption
      – Decreases renal phosphate reabsorption

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

  • Question 50 - A 25 year old woman who is a known diabetic is brought to...

    Incorrect

    • A 25 year old woman who is a known diabetic is brought to the ED with diabetic ketoacidosis. She promptly received an insulin infusion. Which of the following are expected to increase upon infusion of insulin?

      Your Answer:

      Correct Answer: Blood pH

      Explanation:

      Ketoacidosis is characterized by hyperglycaemia, glycosuria, hyperkalaemia, and metabolic acidosis with respiratory compensation. An insulin infusion would be able to address these by lowering blood glucose through increased insulin-mediated cellular uptake, lowering urine glucose concentration as cellular glucose uptake is increased, decreasing K+ in her blood by shifting it into cells, and increasing blood ph by addressing the metabolic acidosis. The metabolic acidosis is addressed by the reduction of ketoacids production thereby returning her blood ph to normal and reducing the need for compensatory hyperventilation.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Endocrine (2/6) 33%
Pharmacology (0/2) 0%
Physiology (2/4) 50%
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