Portal capillaries carry releasing hormones from the brain to the:

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: 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.

Correct Answer: D

Rationale: Step 1: ACTH, TSH, and gonadotropins are hormones that stimulate the secretion of other hormones. Step 2: These hormones target specific endocrine glands, such as the adrenal cortex. Step 3: Since these hormones stimulate the secretion of other hormones and target specific glands, they are classified as tropic hormones. Step 4: Thus, the correct answer is D: tropic hormones. Summary: A is incorrect as they are not hypothalamic-releasing hormones. B is incorrect as they are not secreted by the neurohypophysis. C is incorrect as they are not specifically aimed at the adrenal cortex.

Correct Answer: C

Rationale: Step-by-step rationale: 1. ADH (antidiuretic hormone) regulates water balance by increasing water reabsorption in the kidneys. 2. A deficiency of ADH leads to decreased water reabsorption, resulting in increased urine output (polyuria). 3. Polyuria causes dehydration, electrolyte imbalances, and concentrated urine. 4. Elevated blood glucose levels (choice A) and diabetes mellitus (choice B) are not directly related to ADH deficiency. 5. Expanding blood volume (choice D) would not occur due to decreased water reabsorption. Summary: A deficiency of ADH most likely induces polyuria by decreasing water reabsorption in the kidneys. Elevated blood glucose levels, diabetes mellitus, and expanding blood volume are not direct consequences of ADH deficiency.