Insulin, cortisol, thyroxine, and oxytocin:

Correct Answer: D

Rationale: Rationale: 1. Insulin, cortisol, thyroxine, and oxytocin are all hormones produced by various glands in the body. 2. Insulin is produced by the pancreas, cortisol by the adrenal glands, thyroxine by the thyroid gland, and oxytocin by the hypothalamus and released by the pituitary gland. 3. Each of these hormones plays a different role in the body, such as regulating blood glucose levels, metabolism, stress response, and reproductive functions. 4. Therefore, the correct answer is D: they are all hormones. Summary: A: Incorrect. Hypothalamic-releasing hormones are specific hormones that stimulate the release of other hormones from the pituitary gland. B: Incorrect. Adenohypophysis secretes different hormones, not these specific ones. C: Incorrect. Insulin, for example, decreases blood glucose levels, while cortisol increases blood glucose levels.

Correct Answer: C

Rationale: Ketoacidosis is most related to excess fatty acid catabolism. During this process, the body breaks down fatty acids into ketones, leading to an accumulation of ketones in the blood and causing metabolic acidosis. Adrenocortical insufficiency (A) is related to cortisol deficiency, not ketoacidosis. Cushing syndrome (B) is associated with excess cortisol production, not ketoacidosis. Hyperglycemia (D) is high blood sugar levels and is not directly related to the mechanism of ketoacidosis.

Correct Answer: D

Rationale: Step-by-step rationale: 1. The anterior pituitary gland is connected to the hypothalamus by the portal capillaries. 2. This connection allows for the transport of releasing hormones from the hypothalamus to the anterior pituitary. 3. Releasing hormones stimulate the anterior pituitary to release specific hormones. 4. This communication pathway is essential for regulating hormone production and maintaining homeostasis. Summary of other choices: A: Incorrect. The neurohypophysis refers to the posterior pituitary, not the anterior pituitary. B: Incorrect. ADH and oxytocin are released from the posterior pituitary, not the anterior pituitary. C: Incorrect. Releasing hormones are produced by the hypothalamus, not the anterior pituitary.

Correct Answer: C

Rationale: The correct answer is C: Stimulating hepatic gluconeogenesis. Insulin's primary function is to lower blood glucose levels by promoting glucose uptake in cells and inhibiting gluconeogenesis in the liver. Choice A is correct as insulin helps lower blood glucose levels. Choice B is correct as insulin promotes protein synthesis. Choice D is correct as insulin promotes fatty acid synthesis to store excess glucose as fat. Therefore, choice C is incorrect as insulin actually inhibits hepatic gluconeogenesis rather than stimulating it.

Correct Answer: A

Rationale: The correct answer is A: are concerned with lactation. Both prolactin and oxytocin are hormones involved in lactation. Prolactin promotes milk production in the mammary glands, while oxytocin stimulates the release of milk from the breasts during breastfeeding. Therefore, both hormones play crucial roles in the lactation process. Choice B is incorrect because oxytocin is secreted by the posterior pituitary gland, not the adenohypophysis. Choice C is incorrect because oxytocin specifically stimulates the contraction of the muscles around the mammary glands to release milk, not the production of milk. Choice D is incorrect because oxytocin is also involved in milk ejection, not just lactation itself.