Oxytocin:

Correct Answer: A

Rationale: Rationale: 1. Oxytocin is a neurohypophyseal hormone secreted by the posterior pituitary gland. 2. It plays a key role in stimulating uterine contractions during labor and childbirth. 3. This action helps in the progression of labor by promoting the expulsion of the fetus. 4. Oxytocin also stimulates milk ejection during breastfeeding. 5. Choice A is correct as it accurately describes the role of oxytocin in uterine muscle contraction. Summary: B: Oxytocin is not a gonadotropin; it does not directly affect gonadal function. C: Oxytocin does not stimulate the kidney to reabsorb Na+ and water; that is the role of other hormones like aldosterone. D: Oxytocin is not a mineralocorticoid; it does not regulate electrolyte balance like mineralocorticoids do.

Correct Answer: D

Rationale: The correct answer is D: polyphagia. Polyphagia is the medical term for excessive eating despite adequate glucose levels in the blood, commonly seen in conditions like diabetes mellitus. This excessive hunger is due to the body's inability to use glucose effectively, leading to a constant feeling of hunger. A: Acidosis refers to an excess of acid in the blood, not related to excessive eating. B: Polyuria is excessive urination, not directly related to excessive eating. C: Polydipsia is excessive thirst, also not directly related to excessive eating. In summary, polyphagia is the correct term for excessive eating despite adequate glucose levels, while the other choices are unrelated to this specific symptom.

Correct Answer: C

Rationale: The correct answer is C: raise blood glucose levels. Glucagon, growth hormone, cortisol, and epinephrine all work together to increase blood glucose levels through various mechanisms. Glucagon stimulates the breakdown of glycogen into glucose, growth hormone promotes gluconeogenesis, cortisol increases blood sugar through gluconeogenesis and inhibiting glucose uptake, and epinephrine triggers glycogen breakdown and inhibits insulin release. Choices A, B, and D are incorrect because not all of these hormones are secreted by the adrenal gland, they do not directly expand blood volume, and they do not stimulate osteoclastic activity, respectively.

Correct Answer: B

Rationale: The correct answer is B: PTH. Parathyroid hormone (PTH) regulates calcium levels in the body by acting on bones, kidneys, and intestine. PTH stimulates release of calcium from bones, reabsorption of calcium in kidneys, and absorption of calcium in the intestine. T3 and T4 are thyroid hormones that do not directly regulate calcium levels. ACTH is adrenocorticotropic hormone that stimulates the adrenal glands. Oxytocin is a hormone involved in labor and lactation, not calcium regulation.

Correct Answer: B

Rationale: Excess insulin leads to increased glucose uptake by cells, causing a drop in blood sugar levels, resulting in hypoglycemia. This can lead to symptoms like confusion, sweating, and weakness. Ketosis (A) is caused by low insulin levels, hypertension (C) is not directly related to excess insulin, and diuresis (D) is more commonly associated with conditions like diabetes insipidus.