Cell fragments called platelets, or thrombocytes, make up about 2 percent of blood. Platelets stop blood loss from damaged vessels. When a blood vessel tears, platelets at the site adhere to the wall of the vessel to close the tear. READ MORE

red blood cells

Red blood cells

The bloodstream delivers oxygen to cells and removes carbon dioxide waste through a process called internal respiration. In the lungs, oxygen is absorbed into the erythrocytes in the blood stream. These cells, commonly called red blood cells, contain gas-transporting molecules READ MORE