Question

Melanin is a skin pigmentation that absorbs and dissipates broadband UV rays. Since UV radiation causes DNA damage, melanin pigments protect the skin and reduce the risk of cancer. When skin is exposed to sunlight, melanin production is increased, causing the skin to tan. This demonstrates that

A. the expression of some genes is influenced by the environment
B. the environment causes mutations that have a large effect on the chance of survival
C. the environment causes mutations that increase the chance of survival
D. the environment causes mutations that have no effect on the chance of survival

Answer 1

The increase in melanin production due to sun exposure is an adaptive response where gene expression is influenced by environmental factors, acting to protect the skin from UV-induced DNA damage.

Step-by-step explanation:

The increase in melanin production when the skin is exposed to sunlight is an example of how the expression of some genes is influenced by the environment. Melanin serves as a protective pigment that absorbs UV radiation, minimizing DNA damage and reducing the risk of skin cancer. The environmental factor here, which is sunlight exposure, does not cause mutations but rather induces a physiological response that leads to increased melanin production for protection.