is/are synthesized by the endoplasmic reticulum-Golgi complex mechanism.

Correct Answer: A

Rationale: Peptides are synthesized and packaged via the ER-Golgi system.

Correct Answer: A

Rationale: Diurnal rhythms (e.g., cortisol) follow a 24-hour cycle linked to light-dark patterns.

Correct Answer: C

Rationale: The pineal gland synthesizes melatonin.

Correct Answer: D

Rationale: Oxytocin is not tropic; it directly affects target tissues.

Correct Answer: D

Rationale: GH increases protein synthesis, not decreases it.