Underproduction of growth hormone during the growing years produces ______.

Correct Answer: C

Rationale: The correct answer is C: pituitary dwarfism. Growth hormone deficiency during growing years results in pituitary dwarfism due to stunted growth. Myxedema (choice A) is associated with hypothyroidism, not growth hormone deficiency. Gigantism (choice B) occurs due to excessive growth hormone production in childhood. Acromegaly (choice D) is caused by excess growth hormone in adulthood, not during the growing years. Thus, choice C is the most appropriate based on the impact of growth hormone deficiency on growth during childhood.

Correct Answer: D

Rationale: The correct answer is D because testosterone is not controlled by the thyroid gland. Testosterone is primarily produced in the testes and regulated by the hypothalamus and pituitary gland. The other choices (A, B, C) are all true of testosterone. Testosterone is responsible for the growth of the penis and testes (A), development of male secondary sex characteristics (B), and can potentially lead to baldness due to its effects on hair follicles (C). Thyroid gland primarily regulates metabolism and energy levels, not testosterone production.

Correct Answer: D

Rationale: The correct answer is D: GH (Growth Hormone). GH is the most abundant hormone produced by the anterior pituitary gland. It plays a crucial role in regulating growth, metabolism, and cell repair. LH, TSH, and ACTH are also hormones produced by the anterior pituitary, but they are not as abundant as GH and do not have the same wide-ranging effects on the body. LH is involved in reproductive functions, TSH regulates thyroid function, and ACTH stimulates the adrenal glands. Therefore, based on the function and abundance of hormones produced by the anterior pituitary, GH is the correct answer.

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: folate. Folate absorption is not Na+ dependent as it is primarily absorbed in the small intestine through a carrier-mediated process that is independent of sodium. Thiamin, riboflavin, and niacin absorption, on the other hand, are Na+ dependent processes that rely on sodium co-transporters for uptake in the small intestine. Thiamin is absorbed through a sodium-dependent active transport system, riboflavin requires a sodium-dependent carrier protein for absorption, and niacin absorption involves a sodium-dependent transporter in the small intestine. Therefore, folate is the only option that is not Na+ dependent for absorption.