RBCs also referred to asErythrocytes, have a protein known as hemoglobin. The blood gets its color while hemoglobin absorbs oxygen from the lungs. As the blood travels through the body, the hemoglobin releases the oxygen in the tissues. RBCs have a life span of four months and that they appear in the form of flat indented discs.

The WBCs additionally referred to as Leukocytes, manage more complex functions. They are the defense mechanism of the human body for fighting infections. There are different types of WBCs with varied lifestyles cycles and important functions. White blood cells also produce a special protein called antibody which recognizes and fights the presence of overseas elements within the body. Their lifespan is around 1 week to 1 month.

Half of the blood volumed consists of RBCs and around 1% only consists of WBCs. One type of RBCs is found as compared to five known types of WBCs.