2. Variation in a a trait is a required condition for natural selection to act on a population for that trait. Assuming a population of organisms only started with only one form of a trait, what are two ways
variation in the trait could be introduced into the population? Explain your answer.

You have just sequenced a new protein found in mice and observe that sulfur-containing cysteine residues occur at regular intervals. what is the significance of this finding? it will be important to include cysteine in the diet of the mice. cysteine residues are required for the formation of α helices and β pleated sheets. cysteine residues are involved in disulfide bridges that form tertiary structure. cysteine causes bends, or angles, to occur in the tertiary structure of proteins.