Which endocrine gland normally produces insulin?

Correct Answer: C

Rationale: The correct answer is C: Pancreas. The pancreas is the endocrine gland responsible for producing insulin, which regulates blood sugar levels. It is located behind the stomach and plays a crucial role in maintaining glucose balance in the body. The other choices, A: Adrenal, B: Parathyroid, and D: Liver, do not normally produce insulin. Adrenal glands produce hormones like adrenaline and cortisol, the parathyroid regulates calcium levels, and the liver performs various metabolic functions but does not produce insulin. Therefore, the pancreas is the correct choice for insulin production.

Correct Answer: D

Rationale: The correct answer is D: stomach. Proteins are broken down into amino acids through the process of digestion. In the stomach, proteins are broken down into smaller peptides, not free amino acids. The final step of liberating proteins into free amino acids occurs in the enterocyte cytoplasm, where absorbed nutrients are further processed. The brush border of the small intestine is where the final stages of digestion take place before absorption. The small intestine lumen is the space where digestion occurs, but the actual liberation of proteins into free amino acids happens in the enterocyte cytoplasm.

Correct Answer: D

Rationale: The correct answer is D: acetylcholine. Parietal cells in the stomach are primarily stimulated by acetylcholine to secrete hydrochloric acid. Acetylcholine binds to muscarinic receptors on parietal cells, leading to an increase in intracellular calcium levels and subsequent acid secretion. Prostaglandins (choice A) actually inhibit acid secretion, making it an incorrect choice. Aspirin (choice B) is known to damage the gastric mucosa and does not directly stimulate parietal cells. Vinegar (choice C) is acidic but does not specifically target parietal cells for acid secretion. Therefore, the correct choice is acetylcholine as it directly stimulates parietal cell secretion through muscarinic receptors.

Correct Answer: B

Rationale: Step 1: Albumin binds more thyroid hormones than TBG due to its higher concentration in the blood. Step 2: TBG has higher affinity for thyroid hormones than albumin, leading to less free hormone. Step 3: Hence, choice B is correct as albumin has more capacity to bind thyroid hormones. Summary: Choice A is incorrect as significant T3 is produced peripherally. Choice C is incorrect as TBG has higher affinity. Choice D is incorrect as thyroid hormones stimulate lipolysis, not lipogenesis.

Correct Answer: A

Rationale: The correct answer is A: follicle-stimulating hormone (FSH). FSH is the other hormone made by the pituitary gland that helps regulate reproductive cells, along with luteinizing hormone (LH). FSH is responsible for stimulating the growth and maturation of ovarian follicles in females and spermatogenesis in males. Explanation: 1. FSH is directly involved in the reproductive process by stimulating follicle development and sperm production. 2. Epinephrine and norepinephrine are not hormones produced by the pituitary gland and are involved in the stress response. 3. Androgens are male sex hormones produced primarily by the testes, not the pituitary gland. In summary, FSH is the correct answer as it plays a crucial role in regulating reproductive cells, while the other choices are not involved in the reproductive system or are not produced by the pituitary gland.