In a lab investigation we performed, we observed and learned about ABO blood typing. Before this I only had a very basic grasp on what this subject entailed, but now I have new information on things like the antibodies that the body produces and the alleles that control what protein receptors the blood cells have. I also learned about how the blood types can receive or donate to other types and why clotting happens when some blood types are mixed.This knowledge can be easily applied to analysis being done at a crime scene through the blood typing tests that we learned in this lab. What we can do is add some of the A and B antibodies to a given sample and see what it does and does not react to. If it reacts to antibody A, then it is type A. If it reacts to antibody B, then it is type B. If it reacts to both, then it is type AB. If it does not react, then it is type O. Red blood cells can not be DNA tested because they lack a nucleus and therefore DNA. Some questions that come to mind after hearing this are “how do scientists get DNA samples from blood?†and “why even bother testing for blood type at a crime scene anyway?â€. I would at some point like to study this a little further to find answers to these questions.