Melatonin level change naturally in response to

Melatonin level change naturally in response to

• A. Stress Hormones
• B. Androgens and estrogens
• C. Sleep-wake cycles
• D. The amount of light

Answer: (D)

Melatonin is produced by the pineal gland in response to light and darkness, helping signal when it’s time to sleep. Light detected by the eyes sends signals to the brain’s clock (the suprachiasmatic nucleus) to suppress melatonin production, so daytime light keeps melatonin low. When light levels fall, this inhibition lifts and melatonin levels rise, promoting sleepiness. While sleep-wake patterns and other hormones interact with melatonin, the immediate, natural trigger for its fluctuation is the amount of light.

Melatonin is produced by the pineal gland in response to light and darkness, helping signal when it’s time to sleep. Light detected by the eyes sends signals to the brain’s clock (the suprachiasmatic nucleus) to suppress melatonin production, so daytime light keeps melatonin low. When light levels fall, this inhibition lifts and melatonin levels rise, promoting sleepiness. While sleep-wake patterns and other hormones interact with melatonin, the immediate, natural trigger for its fluctuation is the amount of light.