The secretion of parathyroid hormone is a good example of __________.

Correct Answer: B

Rationale: The correct answer is B: humoral stimuli. Parathyroid hormone secretion is regulated by the concentration of calcium in the blood, which is an example of humoral stimuli. When blood calcium levels decrease, parathyroid hormone is released to increase calcium levels. Pituitary gland stimuli (A), neural stimuli (C), and hormonal stimuli (D) are not directly involved in the regulation of parathyroid hormone secretion.

Correct Answer: D

Rationale: Step-by-step rationale: 1. The inferior thyroid artery typically arises from the thyrocervical trunk. 2. The thyrocervical trunk is a branch of the subclavian artery. 3. This artery supplies blood to the thyroid gland. 4. The external carotid artery and internal carotid artery do not give rise to the inferior thyroid artery. 5. The brachiocephalic trunk does not directly supply blood to the thyroid gland. In conclusion, the correct answer is D because the thyrocervical trunk is the main artery that gives rise to the inferior thyroid artery, providing blood supply to the thyroid gland.

Correct Answer: C

Rationale: The correct answer is C: Splenic artery. The splenic artery supplies the tail of the pancreas through its branches. The splenic artery runs along the superior border of the pancreas and gives off multiple branches that supply various parts of the pancreas, including the tail. A: Inferior pancreaticoduodenal artery supplies the inferior part of the pancreas. B: Left gastroepiploic artery supplies the greater curvature of the stomach. D: Superior pancreaticoduodenal artery supplies the pancreatic head and duodenum. Therefore, the splenic artery is the correct answer as it specifically supplies the tail of the pancreas.

Correct Answer: D

Rationale: The correct answer is D because insulin and glucagon are both hormones secreted by the pancreas to regulate blood glucose levels. Insulin is secreted by beta cells in response to high blood glucose levels, promoting glucose uptake by cells. Glucagon is secreted by alpha cells in response to low blood glucose levels, stimulating the release of stored glucose. Choices A and C are incorrect because insulin is secreted by beta cells, not glucagon, and they are secreted in response to high, not low, glucose levels. Choice B is incorrect because insulin lowers blood glucose levels, while glucagon raises them.

Correct Answer: A

Rationale: The correct answer is A: Adrenal cortex. The adrenal cortex is associated with producing hormones related to sugar (glucocorticoids), salt (mineralocorticoids), and sex (androgens). Glucocorticoids regulate glucose metabolism, mineralocorticoids regulate salt balance, and androgens are sex hormones. The pancreas primarily regulates blood sugar levels. The parathyroid gland is responsible for calcium and phosphorus balance, not sugar, salt, and sex. The neurohypophysis is part of the pituitary gland and mainly regulates water balance and blood pressure, not specifically sugar, salt, and sex.