First, there are no races in the biological sense in humans—Homo sapiens is a widely distributed, polytypic species, exhibiting considerable genetic diversity within and between the historically defined 'races'.
Second, only a very few heritable traits have been used to construct the racial categories that most of us grow up with.
Third, it's virtually impossible to come up with a racial classification that bears any relation to reality—as soon as one begins to take account of more than a few relatively unimportant traits, the whole idea of racial classification falls flat on its face.
Fourth, unless one is prepared to argue that each and every one of us is a distinct race, the notion of human races has no basis in biology.As such, we must conclude that the notion of human races is grounded not in biology, but in the bigotry inherent in the racial worldview—'races' are part of a masking ideology that perpetuates the social and economic dominance of the ruling strata of society.
All people ought to be given the respect they deserve as members of the unitary human species, and never judged according to the colour of their skin or the culture of their kin.