The authors of your book point out that "race is a social concept, not a scientific one," and specifically define race as "a group of people who share a set of characteristics (usually physical characteristics) deemed by society to be socially significant." (215, 216).
Using functionalism, conflict theory, or symbolic interactionism, explain why it is that even though genetic differences between people who have different physical characteristics are minor (like skin color), we as a society continue to use race as a socially significant category. In other words, according to a functionalist, conflict theorist, and/or symbolic interactionist, in what ways do we make race important?