The blood is composed of a fluid called plasma that contains red blood cells, white blood cells and platelets. The plasma carries the proteins, hormones and minerals from one part of the body to the other. The red blood cells contain hemoglobin which helps to transport oxygen from the lungs to the rest of the body parts. The white blood cells help to fight infections and diseases. The blood platelets help to clot after an injury thereby preventing an excess loss of blood.
