AP BIOLOGY

Detailed explanation-1: -Different eye color is observed in human beings due to mutation. Polyploidy in plants is an example of neutral mutation, where flowers of same plant show difference in color or show two colors.

Detailed explanation-2: -The majority of mutations have neither negative nor positive effects on the organism in which they occur. These mutations are called neutral mutations. Examples include silent point mutations. They are neutral because they do not change the a mino acid s in the proteins they encode.

Detailed explanation-3: -Nature shuffles our genes The mutation of brown eyes to blue represents neither a positive nor a negative mutation. It is one of several mutations such as hair colour, baldness, freckles and beauty spots, which neither increases nor reduces a human’s chance of survival.

Detailed explanation-4: -A mutation whose fixation is independent of natural selection is termed a neutral mutation. Therefore selective neutrality of a mutation can be defined by independence of its fixation from natural selection.

Detailed explanation-5: -Originally, all humans had brown eyes. Some 6, 000 to 10, 000 years ago, a genetic mutation affecting one gene turned off the ability to produce enough melanin to color eyes brown causing blue eyes. This mutation arose in the OCA2 gene, the main gene responsible for determining eye color.