Question

question 1 (1 point)
which of the following statements about melanin is most accurate?
a melanin is found only in human cells and is not present in other organisms.
b human skin color contains only one type of melanin.
c the more eumelanin an individual has in their skin, the darker their skin is.
d the darker a persons skin color is, the more likely uv radiation will damage the dna in their cells

question 2 (1 point)
which of the following statements accurately describe variation in human skin color?
a data support a correlation between uv intensity and skin color variation.
b human skin color variation is mostly determined by the types and amounts of melanin in the skin.
c variations in human skin color can be quantified, or measured.
d on average, the skin color of indigenous peoples around the world correlates with the uv intensity in their environments.

Explanation:

• Question 1: Melanin is not unique to human cells (a is false). Human skin has different types of melanin like eumelanin and pheomelanin (b is false). Eumelanin is a dark - pigmented melanin, and more of it leads to darker skin (c is true). Darker skin provides more protection against UV - induced DNA damage (d is false).
• Question 2: There is a correlation between UV intensity and skin color variation as an evolutionary adaptation (a is true). The types and amounts of melanin in the skin mainly determine skin color (b is true). Skin color can be measured in terms of pigmentation levels (c is true). The skin color of indigenous peoples generally correlates with local UV intensity (d is true).

Answer:

Question 1: C. The more eumelanin an individual has in their skin, the darker their skin is.
Question 2: A. Data support a correlation between UV intensity and skin color variation; B. Human skin color variation is mostly determined by the types and amounts of melanin in the skin; C. Variations in human skin color can be quantified, or measured; D. On average, the skin color of indigenous peoples around the world correlates with the UV intensity in their environments.