Regarding the thyroid gland; All are true Except:

Correct Answer: C

Rationale: The correct answer is C: Its isthmus is at the level of thyroid cartilage. The isthmus of the thyroid gland is located at the level of the cricoid cartilage, not the thyroid cartilage. The thyroid gland is closely related to the inferior (recurrent) laryngeal nerve (A), it moves on swallowing (B), and it is invested by pretracheal fascia together with the parathyroids (D). These choices are correct anatomical characteristics of the thyroid gland.

Correct Answer: C

Rationale: The correct answer is C: anterior pituitary gland. Portal capillaries carry releasing hormones from the hypothalamus to the anterior pituitary gland, where they regulate the release of hormones. Releasing hormones do not target the neurohypophysis (choice A) or the posterior pituitary gland (choice D) directly. They also do not affect the pancreas (choice B) in this context. Thus, the correct answer is the anterior pituitary gland due to its role in receiving and responding to releasing hormones from the hypothalamus.

Correct Answer: C

Rationale: Rationale: 1. Lactogenic hormone stimulates mammary glands to produce milk, essential for lactation. 2. Oxytocin is a different hormone that causes milk ejection, not production. 3. Gonadotropins like FSH and LH affect gonads, not lactation. 4. Choice C directly relates to lactation, making it the correct answer.

Correct Answer: A

Rationale: Step-by-step rationale: 1. Insulin is a hormone that regulates blood glucose levels by promoting glucose uptake into cells. 2. Beta cells of the islets of Langerhans in the pancreas are responsible for secreting insulin. 3. Insulin lowers blood glucose levels by enhancing glucose uptake and storage. 4. Therefore, choice A is correct as it accurately identifies the source of insulin secretion. Summary: - Choice B is incorrect as the liver does not secrete insulin. - Choice C is incorrect as insulin lowers blood glucose levels. - Choice D is incorrect as insulin is released in response to high, not low, blood glucose levels.

Correct Answer: C

Rationale: Correct Answer: C - Diabetes insipidus Rationale: 1. Diabetes insipidus is characterized by excess urine production due to inadequate ADH secretion. 2. Low blood volume occurs as a result of increased urine output, leading to dehydration. 3. Cushing syndrome involves excess cortisol production, not excess urine production. 4. Tetany is caused by low calcium levels, not excess urine production. 5. Oversecretion of ACTH leads to excess cortisol production, not excess urine production.