Thyroxine:

Correct Answer: B

Rationale: Thyroxine is also known as T4, a thyroid hormone produced by the thyroid gland. It plays a crucial role in regulating metabolism. TSH (Thyroid Stimulating Hormone) is a hormone produced by the pituitary gland to stimulate thyroid hormone production, not thyroxine itself. Choice C is incorrect because thyroxine exerts negative feedback on TSH, not T3. Choice D is incorrect as thyroxine actually increases basal metabolic rate. Thus, the correct answer is B as thyroxine is indeed T4.

Correct Answer: D

Rationale: The correct answer is D: Secrete FSH. The hypothalamus produces releasing and inhibiting hormones that regulate the pituitary gland's secretion of hormones such as FSH. The hypothalamus itself does not secrete FSH. A, B, and C are functions of the hypothalamus as it is involved in regulating heart rate, temperature control, and water balance through various hormonal and neural pathways.

Correct Answer: C

Rationale: The correct answer is C: Gonadal. The secretions from gonads (testes in males, ovaries in females) differ between males and females due to the production of sex hormones (testosterone in males, estrogen and progesterone in females). Adrenal glands (A) secrete similar hormones in both genders. Parathyroid (B) and Pancreas (D) do not secrete hormones that differ based on gender.

Correct Answer: A

Rationale: The correct answer is A: lipid soluble. Lipid-soluble hormones can easily pass through the cell membrane and bind to intracellular receptors. This binding activates gene expression and affects protein synthesis within the cell. Water-soluble hormones, like choice B, bind to cell surface receptors and activate signaling pathways through second messengers (choice C). Proteins (choice D) are not hormones but rather macromolecules that can act as signaling molecules or receptors. Lipid solubility is crucial for hormones to exert their effects inside target cells, making choice A the correct answer.

Correct Answer: C

Rationale: The correct answer is C: Oxytocin & ADH. The posterior pituitary stores and releases hormones produced by the hypothalamus. Oxytocin is responsible for uterine contractions during childbirth and milk ejection during breastfeeding. ADH (anti-diuretic hormone) regulates water balance by influencing the reabsorption of water by the kidneys. Growth hormone (GH) and Prolactin are released by the anterior pituitary, not the posterior pituitary. Therefore, choices A, B, and D are incorrect as they do not represent the hormones stored and released by the posterior pituitary.