It's also crucial information to have on hand ... blood type mean? Blood types are determined by antigens -- a substance that triggers an immune response -- on the surface of red blood cells.

Red blood cells, or erythrocytes (RBC), are critical to our health. The typical range for women is between 3.6 and 5.2 ...

Require immediate backup! Narrator: Your blood has different cells with different jobs. Some cells do repairs if you get a cut. Red blood cells deliver oxygen and take away rubbish. And your white ...