Why are or why aren’t you a blood donor? Rhesusnegative.net 2 years ago You can watch this: … and you can watch that: … or read about it: What many donors don’t know: Their blood is sold A blood donation occurs when a person voluntarily has blood drawn and used for transfusions and/or made into biopharmaceutical medications by a process called fractionation. Donation may be of whole blood, or of specific components directly.