Which of the following is an anterior pituitary hormone?

Correct Answer: C

Rationale: The anterior pituitary synthesizes thyroid-stimulating hormone (TSH) to regulate thyroid function. ADH and oxytocin are made in the hypothalamus, stored/released by the posterior pituitary, and cortisol is an adrenal hormone, not pituitary-derived. TSH's production site distinguishes it, crucial for thyroid hormone synthesis and metabolic control, contrasting with stored or peripheral hormones.

Correct Answer: D

Rationale: Alpha cells in the pancreas produce glucagon to raise blood glucose. Autoimmune targeting would impair glucagon, not somatostatin (delta cells), pancreatic polypeptide (PP cells), or insulin (beta cells). Glucagon's direct link to alpha cells distinguishes it, critical for glucose counterregulation, contrasting with other pancreatic hormones.

Correct Answer: B

Rationale: Paracrine signaling involves chemicals (e.g., prostaglandins) affecting nearby cells, like histamine in inflammation acting locally without entering blood. Autocrine signaling targets the secreting cell itself (e.g., cancer cells self-stimulating). Endocrine signaling uses blood to reach distant cells (e.g., insulin from pancreas). 'Neuron' isn't a signaling type neurons use neurotransmitters, often paracrine-like at synapses, but it's distinct. Paracrine's local effect distinguishes it, critical for short-range coordination, unlike self, systemic, or neural mechanisms.

Correct Answer: C

Rationale: Follicle-stimulating hormone (FSH) from the anterior pituitary stimulates spermatogenesis in male testes' Sertoli cells and follicle growth in female ovaries monthly, driving gamete production. Luteinizing hormone (LH) triggers testosterone in males and ovulation/oestradiol in females, not sperm/follicle initiation. Somatostatin inhibits hormone release (e.g., GH), not stimulating reproduction. Thymosin, from the thymus, boosts immunity, not gonadal function. FSH's dual reproductive role distinguishes it, key to fertility, unlike ovulation, inhibition, or immune hormones.

Correct Answer: D

Rationale: Goiter, thyroid enlargement, stems from multiple causes: iodine deficiency impairs T3/T4 synthesis, increasing TSH and colloid; genetic abnormalities (e.g., enzyme defects) disrupt hormone production; anti-thyroid drugs (e.g., propylthiouracil) block synthesis, prompting hypertrophy. 'All' encompasses these, distinguishing goiter's multifactorial etiology, key to diagnosis, contrasting with single-cause disorders.