Ultraviolet (UV) light can penetrate the skin and damage DNA, and it can also destroy the B vitamin folate needed for bone-marrow maturation and the development of red blood cells. On the other hand, exposure to ultraviolet light is beneficial in the synthesis of vitamin D3, which is important for growth, calcium absorption, and bone development. The amount of ultraviolet light that penetrates the skin depends on the skin's pigmentation: more melanin (skin pigment) means less penetration. Which of the statements do you think best describes natural selection as it applies to human skin pigmentation? a. a constant pressure for skin to become more and more pigmented

b. a constant pressure for skin to become less and less pigmented

c. a pressure for darker or lighter skin, depending on the intensity of UV in a geographical region

Question

Biology

Sanaa Carr

16 May, 19:27

Ultraviolet (UV) light can penetrate the skin and damage DNA, and it can also destroy the B vitamin folate needed for bone-marrow maturation and the development of red blood cells. On the other hand, exposure to ultraviolet light is beneficial in the synthesis of vitamin D3, which is important for growth, calcium absorption, and bone development. The amount of ultraviolet light that penetrates the skin depends on the skin's pigmentation: more melanin (skin pigment) means less penetration. Which of the statements do you think best describes natural selection as it applies to human skin pigmentation? a. a constant pressure for skin to become more and more pigmented

b. a constant pressure for skin to become less and less pigmented

c. a pressure for darker or lighter skin, depending on the intensity of UV in a geographical region

+2

Answers (1)

Know the Answer?

Melina Ramsey · Answer 1

The correct answer is option c. "a pressure for darker or lighter skin, depending on the intensity of UV in a geographical region".

Explanation:

Humans exposure to ultraviolet light have both, beneficial and harmful effects. In consequence, human skin pigmentation have adaptated to receive different levels of ultraviolet light by synthesizing different levels of melanin (a pigment that protects skin to ultraviolet light) depending on the intensity of UV in a geographical region. This process have been occuring during human evolution history, and it explains why human pigmentation differs among human races.