Answer:they increase the amount of oxegon surronding air.
False; Melanin absorbs and dissipates the harmful UV rays that can damage the DNA of your skin cells. Keratin is a fibrous protein that helps to protect skin from abrasion.
Natural selection :) In simple terms in the one with the best traits will repopulate so they can have the best traits the individuals who are weak typically die off and no one breeds with them :)
Explanation:
Taking Xx as heterozygous and XX for normal
Woman =Xx Man =XX
all possible outcomes are XX, XX, XX and Xx
there is 0 probability of having a colorblind child
(But there is a 25 % chance that the child may be a carrier like its mother)