SEM image of a white blood cell, platelet, and red blood cell. White blood cells or leucocytes (far right) fight infection by producing antibodies or devouring invading bacteria. Red blood cells or erythrocytes (far left) carry oxygen from the lungs to the rest of the body. Platelets (middle) are cell fragments that play a role in the ability of blood to clot.
Facts about Blood/Blood Cells Facts: Function of whole Blood, function platelets, function red/white blood cells
The functions of blood explained in detail and the explanation of the functions of the four main components of blood (plasma, red blood cells (erythrocytes), white blood cells (leukocytes) and platelets (thrombocytes) can be read in this article.