A physiology student is reviewing hormones involved in circadian rhythms. Which statement about melatonin is FALSE?

• A. Melatonin secretion generally increases in darkness
• B. Melatonin is primarily released from the pineal gland
• C. Melatonin plays a role in regulating sleep timing
• D. Melatonin production is stimulated by exposure to bright light

Answer: (D)