The document summarizes the components and functions of blood. Blood has two main components - blood cells and plasma. There are three types of blood cells - red blood cells, white blood cells, and platelets. Red blood cells transport oxygen and carbon dioxide throughout the body. White blood cells fight infections. Platelets help stop bleeding by causing blood clots. Plasma is the liquid portion of blood and transports nutrients, waste, hormones, and gases. Overall, blood performs essential functions like transport, protection, and temperature regulation.