Nokea
Cortisol secretion is directly stimulated by:
- A. Aldosterone
- B. Prolactin
- C. ACTH
- D. CRH
Correct Answer: C
Rationale: Cortisol secretion is directly stimulated by adrenocorticotropic hormone (ACTH), which is produced and released by the anterior pituitary gland in response to corticotropin-releasing hormone (CRH) from the hypothalamus. ACTH acts on the adrenal cortex to stimulate the production and release of cortisol. Aldosterone is another hormone produced by the adrenal cortex, but it is not directly involved in the stimulation of cortisol secretion. Prolactin is a hormone produced by the pituitary gland that plays a role in lactation, not cortisol secretion. High blood potassium levels can stimulate aldosterone secretion but do not directly stimulate cortisol secretion.
You may also like to solve these questions
All are features of diabetic ketoacidosis except:
- A. Hyperthermia
- B. Drowsiness
- C. Dehydration
- D. Air hunger
Correct Answer: A
Rationale: Hyperthermia is not a typical feature of diabetic ketoacidosis (DKA). DKA is typically characterized by high blood sugar levels, ketone accumulation, metabolic acidosis, dehydration, drowsiness, and, in severe cases, unconsciousness. Common symptoms include drowsiness, dehydration, and air hunger (deep and rapid breathing). However, hyperthermia, which refers to an elevated body temperature, is not a characteristic typically associated with DKA. It is important to monitor and manage DKA promptly as it is a serious complication of diabetes that requires immediate medical attention.
Thyrotoxicosis may be featured by all except:
- A. Myopathy
- B. Pretibial myxoedema
- C. Hypernatraemia
- D. Atrial fibrillation
Correct Answer: A
Rationale: Thyrotoxicosis, also known as hyperthyroidism, is a condition characterized by excessive thyroid hormone production by the thyroid gland. Symptoms of thyrotoxicosis can include weight loss, heat intolerance, tremors, hyperactivity, and fatigue. While musculoskeletal symptoms such as weakness and tremors are common in thyrotoxicosis, true myopathy (muscle disease) is not a typical feature of the condition. Therefore, myopathy is the correct choice among the given options.
Which of the following hormones are produced in the anterior pituitary gland?
- A. Oxytocin
- B. Prolactin
- C. Adrenocorticotrophic hormone (ACTH)
- D. Follicle-stimulating hormone (FSH)
Correct Answer: D
Rationale: Follicle-stimulating hormone (FSH) is one of the hormones produced in the anterior pituitary gland. The anterior pituitary gland secretes several hormones that regulate various functions in the body. FSH plays a crucial role in both males and females. In females, FSH stimulates the growth and maturation of ovarian follicles, which contain the eggs. In males, FSH is essential for the production of sperm in the testes. The production and release of FSH are regulated by the hypothalamus and gonadotropin-releasing hormone (GnRH).
Which of the following is the most potent stimulus for hypothalamic production of arginine vasopressin?
- A. Hypertonicity
- B. Hyperkalemia
- C. Hypokalemia
- D. Hypotonicity
Correct Answer: A
Rationale: Hypertonicity (increased osmolarity or high concentration of solutes in the blood) is the most potent stimulus for the hypothalamic production of arginine vasopressin (also known as antidiuretic hormone or ADH). When the body senses increased plasma osmolality, the osmoreceptors in the hypothalamus stimulate the release of vasopressin from the posterior pituitary gland. Vasopressin acts on the kidneys to increase water reabsorption and decrease urine output, helping to restore normal osmolarity. This mechanism helps to conserve water and maintain body fluid balance in response to dehydration or increased solute concentration in the blood.
Which of the following is not a symptom of Cushing's syndrome?
- A. Easy bruising
- B. Weight gain
- C. Acne
- D. Weight loss
Correct Answer: D
Rationale: Weight gain is a common symptom of Cushing's syndrome due to the excessive production of cortisol, a hormone that regulates metabolism and fat storage. The other symptoms listed, such as easy bruising, acne, and stretch marks, are also characteristic features of Cushing's syndrome. However, weight loss is typically not associated with this condition. In fact, individuals with Cushing's syndrome often experience unexplained and rapid weight gain, especially in the face, abdomen, and upper back (resulting in a characteristic "buffalo hump" appearance), rather than weight loss.