picture from CELLS
is a living tissue composed of blood cells suspended in plasma.
The cellular elements, red blood cells, white blood cells and
platelets -- make up about 45% of the volume of whole blood. Plasma, which
is 92% water, makes up the remaining 55%.
Blood accounts for about 7% of a person's weight. An average sized man
has about 12 pints of blood, and an average sized woman has about 9
pints. Your body immediately begins replacing the donated blood volume
after you donate blood, so you can safely donate as often as 6 times a
After donation, Blood Center laboratory personnel separate whole blood
into its components:
Plasma - Plasma is 92% water,
miscellaneous elements and 7% protein from which derivatives are made.
Cryoprecipitate (which contains the antihemophilic factor) and fresh
frozen plasma are given to patients who have hemophilia and other bleeding
Platelets - Platelets act to
induce clotting and control bleeding.
Red Blood Cells - Red blood cells
transport oxygen and nutrients to the tissues and remove carbon dioxide
and waste. Red blood cells are indicated for more than 70% of all
transfusions. Accident victims, patients with ulcers and patients
undergoing surgery use red blood cells.
Facts about Blood and Blood Donation (pdf file)
For more information about blood visit
Blood Centers Web Site. Special thanks to Jim Sullivan and CELLS
Alive for the use of graphics and pictures they supplied.