There are four components - or parts - of the blood: red blood cells, white blood cells, plasma and platelets. Blood carries things you need, like oxygen and glucose, and waste products ...

Red blood cells (erythrocytes) are one of three main components in your blood, along with white blood cells and platelets. Produced by your bone marrow, red blood cells play a key role in ...

Some of the major components of your immune system include your skin, tonsils, spleen, bone marrow, white blood cells, and lymph nodes. Several factors, including sleep, nutrition, stress ...