Erythrocytes comprise the majority of cells in peripheral blood numbering roughly 4 x 10^12/l blood. Their main function is to transport oxygen from the lungs to the rest of the body and carbon dioxide in the opposite direction. An erythrocyte normally lives for 120 days in the blood stream before it is removed by the reticulo-endothelial system. A decrease in number of the erythrocytes is called anemia, an increase is called polycytemia.

This course includes lectures in variation in size, shape and color.

The course has been created by Lars Hjorth, MD and Stanislaw Garwicz, MD, PhD, both at the Department of Pediatrics, University Hospital in Lund, Sweden, 2000.