Melanin production is stimulated by _________.

• A. Sleep
• B. Exercise
• C. Diet
• D. Exposure to sunlight

Answer: (D)

Sunlight exposure triggers melanin production in the skin as a protective response to UV radiation. When UV rays reach the skin, signals from nearby skin cells stimulate melanocytes to ramp up melanin synthesis. The process mainly involves the enzyme tyrosinase making more melanin from tyrosine, and the pigment is packaged into melanosomes that are then transferred to surrounding skin cells. This results in darker skin or a tan, which helps absorb UV light and shield skin cells from DNA damage.

Sleep, exercise, and diet don’t directly drive the production of melanin in the skin. While overall health can influence many bodily processes, the specific trigger for melanin synthesis is UV exposure from sunlight.