All the following are endocrine glands, EXCEPT the:

Correct Answer: A

Rationale: The correct answer is A: sweat gland. Endocrine glands secrete hormones directly into the bloodstream, affecting distant target organs. Sweat glands, on the other hand, are exocrine glands that release sweat onto the skin surface to regulate body temperature. The adrenal glands, thyroid gland, and pituitary gland are all endocrine glands that secrete hormones, making them the correct choices. A sweat gland does not secrete hormones into the bloodstream, so it does not qualify as an endocrine gland.

Correct Answer: B

Rationale: The correct answer is B: Adrenal gland. The adrenal gland is located just superior to the kidneys. It is part of the endocrine system and plays a crucial role in producing hormones such as cortisol and adrenaline. The pituitary gland (A) is located in the brain, the pancreas (C) is situated in the abdomen, and the ovaries (D) are found in the pelvic region. The adrenal gland's location and function make it the most appropriate choice in this scenario.

Correct Answer: C

Rationale: The correct answer is C: Acromegaly. Hypersecretion of growth hormone in adults leads to acromegaly, characterized by enlarged hands, feet, and facial features. This occurs due to excess GH after epiphyseal plate closure. A: Cretinism is caused by congenital hypothyroidism, not GH hypersecretion. B: Myxoedema is a severe form of hypothyroidism, not related to GH. D: Graves disease is an autoimmune disorder causing hyperthyroidism, not GH hypersecretion.

Correct Answer: D

Rationale: The correct answer is D: islets of Langerhans. These clusters of cells within the pancreas are responsible for producing insulin. Insulin is a hormone that regulates blood sugar levels. The ovaries (A) and testes (B) are not responsible for insulin production. The hypothalamus (C) plays a role in regulating many bodily functions, but it is not directly involved in insulin production.

Correct Answer: C

Rationale: Homeostasis is the maintenance of a stable internal environment to support optimal physiological functioning. It involves mechanisms that regulate variables within a narrow range. Negative feedback is a key mechanism in maintaining homeostasis by counteracting deviations from set points. Positive feedback amplifies changes and is not involved in maintaining stability. Metabolism refers to the chemical processes in the body and is not specifically related to the maintenance of internal stability. Therefore, the correct answer is C (homeostasis) because it directly relates to the concept of maintaining a stable internal environment through regulatory mechanisms.