2. Stop That Bleeding You are a clinical blood technician of a hospital. You are called to the emergency room, where you find an injured teenager (Tim). His right thigh has been ripped open, and the emergency room medical team is trying to stop the flow of blood from a major artery. Four of his friends wait in the emergency room lobby to donate blood to their friend. What do you suppose doctors are doing to stop the flow of blood? Tim has B+ blood, which friend (s) can donate blood to Tim?

3. Rhiddi and Brianna use anti-A and anti-B serums to determine ABO blood types and RH factor. These young scientists are observing how blood clots as well.

4. After determining the blood type of the four friends, students used the chart below to determine who could donate blood to Tim.