Question

unit 2 - challenge 2.1: the integumentary (skin) s
what role does melanocyte - stimulating hormone (msh) play in skin color?
a.) it results in melanin production.
b.) it lightens the skin.
c.) it causes skin freckles.
d.) it reduces pigmentation.

Explanation:

Melanocyte - stimulating hormone (MSH) acts on melanocytes (cells that produce melanin). MSH binds to receptors on melanocytes and stimulates the production of melanin. Melanin is the pigment responsible for skin color. Options b (lightens skin) and d (reduces pigmentation) are incorrect as MSH increases pigment - related activity. Option c (causes freckles) is incorrect because freckles are due to concentrated melanin production in certain areas, not directly caused by MSH in the sense of being its main role. MSH's main role is to stimulate melanin production.

Answer:

A. It results in melanin production.