What are scientific names for 3 types of blood cells?

Three types of blood cells, I suppose, would be red blood cells (erythrocytes), white blood cells (leukocytes), and platelets.

Red blood cells are the main oxygen carriers in the circulatory system. They do so by holding large amounts of hemoglobin within them. The oxygen binds to the hemoglobin. Upon erytrogenesis (the creation of new red blood cells), they completely push out their nuclei in order to make room for more hemoglobin (awesome, right?).

White blood cells come in three varieties: neutrophils, basophils, and eosinophils. I won't go into the details with these, partially because I'm not an immunologist and would likely get their differences wrong. Anyway, they are responsible for our major immune responses. T-cells and B-cells exist within this category, with one holding a vast arsenal of immunoglobulins (antibodies) and the other working as memory cells, holding a "memory bank" of potential "enemies" (antigens - those which can elicit an immune response).

And then we have platelets. Just know that these are responsible for coagulation, or blood clotting, which is important for the healing process after breaking skin.

All of these are floating around in what is called blood plasma, which is a 95% water solution.

Hope this helps! Double check the identification of B-cells and T-cells.