The rate of metabolism of all body cells is regulated by

Correct Answer: D

Rationale: Thyroid hormone (T3/T4) sets cellular metabolic rate, influencing energy production body-wide. Parathyroid hormone and calcitonin manage calcium, aldosterone fluid/electrolytes not metabolism universally. Thyroid hormone's broad metabolic control distinguishes it, essential for energy regulation, contrasting with ion-specific hormones.

Correct Answer: D

Rationale: The hypothalamus (forebrain) and pineal (epithalamus) are brain-located endocrine glands; the former regulates via releasing hormones, the latter secretes melatonin for sleep. Thymus (chest), parathyroid (neck), and thyroid (neck) are external. Only hypothalamus, pineal, and pituitary (also brain) fit, but 'hypothalamus and pineal' is the pair. This brain-centric role distinguishes them, key to neuroendocrine integration, contrasting with peripheral glands.

Correct Answer: D

Rationale: The pituitary gland, dubbed the 'master gland,' controls other endocrine glands (e.g., thyroid via TSH, adrenals via ACTH) through tropic hormones. Thyroid regulates metabolism, pineal sleep, adrenals stress not others. Pituitary's anterior/posterior lobes orchestrate this, distinguishing its hierarchical role, vital for endocrine harmony, contrasting with effector glands.

Correct Answer: C

Rationale: Prostaglandins (e.g., PGE2) increase renin secretion from juxtaglomerular cells, boosting RAAS during inflammation or low perfusion. High Na/Cl at macula densa or high arteriole pressure (stretch) suppress renin negative feedback signals adequacy. ADH conserves water, not directly affecting renin. Prostaglandins' stimulatory role distinguishes them, critical for RAAS activation in stress, unlike inhibitory or unrelated factors.

Correct Answer: A

Rationale: Glucagon raises glucose via glycogenolysis without increasing lactate gluconeogenesis (lactate source) is secondary. Insulin uses GLUT2 in liver, not GLUT4 (muscle/adipose). Cortisol boosts gluconeogenesis, not glycogenolysis primarily. Glucagon stimulates insulin short-term, not inhibits. Glucagon's lactate-free glucose rise distinguishes it, key to its hepatic action, unlike transporter, cortisol, or insulin errors.