Source: Blood Count image, Public Domain: http://en.wikipedia.org/wiki/File:ABO_blood_group_diagram.svg; Eurythropoietin image, Public Domain: http://en.wikipedia.org/wiki/File:Illu_blood_cell_lineage.jpg
The number of red blood cells in a microliter of blood.
Another word for red blood cells.
A hormone secreted by the kidneys when oxygen levels in blood are too low to stimulate bone marrow to produce more red blood cells.
Cells found in the blood that carry oxygen and carbon dioxide.