"Race" isn't a biological reference. It is partially a reference to the genealogical and/or geographical origin of different groups of people. It doesn't denote differences within the species or physical superiority or inferiority of various groups of humans. Any physical differences between people of different races can be attributed to the geographical origin of their ancestors. More than anything else, it denotes cultures with which people can identify.
"Racism" is a different type of sociological concept than mere identification of cultures. It involves biased treatment of people based on their cultural, genealogical, and geographical identities. It does far more than acknowledge differences. It bases behavior on an unfair application of those differences. Being human means seeing, respecting, and understanding the similarities and differences between the many races of people. Racism is an unhealthy and unfair application of that understanding.
While the term "race" is used primarily to refer to the existence of specific and unique cultures, it can also be used to refer to all of humanity, as in the "human race." This is an inclusive term which emphasizes the commonalities shared by all of humanity. Used in this sense, it represents unity, rather than division.