The endocrine gland(s) referred to as the 'master gland' is the:

Correct Answer: D

Rationale: The correct answer is D: pituitary gland. The pituitary gland is often referred to as the 'master gland' because it controls the functions of other endocrine glands in the body. It secretes hormones that regulate various bodily functions such as growth, metabolism, and reproduction. It is located at the base of the brain and is divided into two parts: anterior and posterior. The anterior pituitary gland produces and releases several important hormones that influence other endocrine glands. The other choices (A: pancreas, B: adrenal glands, C: thyroid gland) do not have the same broad regulatory control over the endocrine system as the pituitary gland.

Correct Answer: B

Rationale: The correct answer is B: To regulate serum calcium levels. The parathyroid gland secretes parathyroid hormone (PTH) to regulate calcium levels in the blood. PTH increases calcium levels by stimulating bone resorption, enhancing calcium absorption in the intestines, and promoting calcium reabsorption in the kidneys. Choices A, C, and D are incorrect because the primary function of the parathyroid gland is specifically related to calcium regulation, not general metabolic homeostasis, signaling to other glands, or receiving signals from the hypothalamus.

Correct Answer: B

Rationale: The correct answer is B: ADH (antidiuretic hormone). Diabetes insipidus is a condition characterized by excessive thirst and urination due to a deficiency of ADH, which regulates water balance in the body. Insulin (choice A) is related to diabetes mellitus, not diabetes insipidus. Growth hormone (choice C) and oxytocin (choice D) do not play a direct role in water balance regulation. Therefore, choice B is the most appropriate answer for this question.

Correct Answer: A

Rationale: The correct answer is A: Androgens. Androgens, such as testosterone, are responsible for the development of male secondary sexual characteristics, such as facial hair, deep voice, and muscle growth. Follicle-stimulating hormone (B) is involved in sperm production, not male secondary sexual characteristics. Epinephrine (C) and norepinephrine (D) are stress hormones and not related to the development of male secondary sexual characteristics.

Correct Answer: A

Rationale: The correct answer is A: Adrenal. The adrenal gland is responsible for producing adrenaline, also known as epinephrine, which is a hormone released in response to stress or danger. Adrenaline helps the body prepare for fight or flight responses by increasing heart rate, dilating airways, and boosting energy. The other choices, Parathyroid, Gonadal, and Pancreas, are not responsible for producing adrenaline. Parathyroid glands regulate calcium levels, gonadal glands produce sex hormones, and the pancreas produces insulin and digestive enzymes. Therefore, the adrenal gland is the correct answer for the production of adrenaline.