Final answer:
The major components of blood include red blood cells, white blood cells, platelets, and plasma. Each component has a specialized function, such as oxygen transport by RBCs, immune defense by WBCs, clotting by platelets, and transport of various substances by plasma.
Step-by-step explanation:
Components of Blood and Their Functions
The major components of blood include red blood cells (RBCs), white blood cells (WBCs), platelets, and plasma. Red blood cells, also known as erythrocytes, are responsible for carrying oxygen to the body's tissues. They contain hemoglobin, which binds oxygen in the lungs and releases it where it's needed.
White blood cells, or leukocytes, play a crucial role in the body's immune system. They help to defend the body against infectious disease and foreign invaders by identifying and attacking pathogens.
Platelets, or thrombocytes, are small, colorless cell fragments that play a key role in blood clotting. They gather at the site of an injury to form a plug and prevent excessive bleeding.
Plasma is the liquid portion of blood in which RBCs, WBCs, and platelets are suspended. It consists of 90 percent water and contains various substances such as hormones, glucose, proteins, electrolytes, carbon dioxide, and blood cells. Blood plasma also includes important proteins like antibodies and coagulation factors. Meanwhile, blood serum is plasma without the coagulation factors, which are consumed during clot formation.
Overall, blood plays a critical role in the transportation of essential nutrients and gases, defense against pathogens, and maintenance of homeostasis by regulating pH, temperature, and osmotic pressure within the body.