Identify the mechanisms that control the production and release of hormones.

Correct Answer: B

Rationale: The correct answer is B: hormonal, humoral, and neural. Hormonal regulation involves feedback loops where hormone levels control their own production. Humoral regulation involves substances in body fluids influencing hormone release. Neural regulation involves the nervous system influencing hormone production. Option A is incorrect because sensory mechanisms do not directly control hormone production. Option C is incorrect because sensory mechanisms are not typically involved in hormone regulation. Option D is incorrect because hormonal control is a key mechanism that was omitted.

Correct Answer: D

Rationale: The correct answer is D: parathyroid hormone. Calcitonin and parathyroid hormone regulate calcium levels in the blood. Calcitonin lowers blood calcium levels by inhibiting bone resorption, while parathyroid hormone increases blood calcium levels by promoting bone resorption. Thus, they have opposite effects on calcium regulation, making parathyroid hormone the antagonistic hormone to calcitonin. Thyroxine (A), growth hormone (B), and insulin (C) do not directly oppose the action of calcitonin in regulating calcium levels.

Correct Answer: C

Rationale: The correct answer is C: glucagon. Glucagon is the hormone that opposes the actions of insulin by increasing blood glucose levels. When blood sugar levels are low, glucagon signals the liver to release stored glucose, raising blood sugar levels. Cortisol (A) and mineralocorticoids (D) are not directly antagonistic to insulin. Norepinephrine/epinephrine (B) play a role in the fight-or-flight response, but they do not directly counteract insulin's actions on glucose regulation.

Correct Answer: D

Rationale: The correct answer is D: Increases blood calcium level. Parathormone is released by the parathyroid glands in response to low blood calcium levels. It acts to increase blood calcium levels by stimulating the release of calcium from bones, increasing calcium absorption in the intestines, and promoting calcium reabsorption in the kidneys. This helps to maintain proper calcium levels in the body. Choices A, B, and C are incorrect because parathormone does not have any direct effect on blood sodium levels and actually works to increase, not decrease, blood calcium levels.

Correct Answer: D

Rationale: The correct answer is D - Melatonin - Regulates the rate of cellular metabolism. Melatonin is a hormone primarily involved in regulating sleep-wake cycles, not cellular metabolism. A: Calcitonin - Lower blood calcium levels - Correct. Calcitonin is released by the thyroid gland to lower blood calcium levels. B: Parathyroid - Raises blood calcium levels - Correct. Parathyroid hormone is released by the parathyroid glands to raise blood calcium levels. C: Somatostatin - Inhibits release of glucagon - Correct. Somatostatin inhibits the release of glucagon and insulin.