Parathyroid hormone:

Correct Answer: D

Rationale: Parathyroid hormone (PTH) is a hormone produced by the parathyroid glands in response to low blood calcium levels. Its main function is to raise calcium levels in the blood by acting on the bones, kidneys, and intestines. PTH stimulates the release of calcium from the bones, enhances the absorption of calcium by the intestines, and promotes the reabsorption of calcium by the kidneys. Therefore, it is secreted in increased amounts when blood calcium levels are below normal in order to maintain overall calcium balance in the body.

Correct Answer: B

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: B

Rationale: Myxoedema refers to severe hypothyroidism which can lead to neurological manifestations. The correct features associated with myxoedema include delayed relaxation of ankle jerk (Choice A), hypertonia (Choice C), and bradylalia (Choice D). Cerebellar ataxia, which involves incoordination and balance issues due to dysfunction of the cerebellum, is not a typical neurological feature seen in myxoedema.

Correct Answer: A

Rationale: Acromegaly is the condition characterized by the enlargement of the bones of the hands, feet, and face due to the overproduction of growth hormone in adults. This excess growth hormone typically comes from a benign tumor in the pituitary gland, leading to the gradual enlargement of these body parts. Cushing syndrome, on the other hand, is caused by prolonged exposure to high levels of cortisol and is not directly related to bone enlargement. Gigantism is the condition of excessive growth in height due to overproduction of growth hormone occurring in children before the closure of growth plates. Myxedema is a term used to describe severe hypothyroidism and is not directly associated with bone enlargement.

Correct Answer: B

Rationale: Myxoedema coma is a severe form of hypothyroidism that can lead to the slowing down of various body functions, including reduced heart rate (bradycardia). As the condition progresses and the body's metabolism becomes more depressed, one of the compensatory mechanisms is an increase in heart rate (tachycardia) to try to maintain adequate tissue perfusion. Therefore, tachycardia is a characteristic feature of myxoedema coma, rather than hypertension or euthermia which are not typically associated with this condition. Hypoventilation is also a common feature of myxoedema coma due to the decreased metabolic rate and respiratory drive.