Which hormone is released in response to daily variations in light with its levels rising in the bloodstream at dusk, peaking around midnight, and falling again as morning approaches?
A)adrenaline
B)thyroxin
C)melatonin
D)androgen

Question

Quizplus · Accepted Answer

Melatonin is released in response to daily variations in light and is responsible for regulating the body's sleep-wake cycle. Its levels rise in the bloodstream at dusk, peak around midnight, and fall again as morning approaches. Adrenaline and androgen are not involved in regulating the sleep-wake cycle, and while thyroxin does affect metabolism, it is not directly related to daily variations in light.

Which Hormone Is Released in Response to Daily Variations in Light