What are the four components of whole blood?

The four components of whole blood are RBC (red blood cells), WBC (white blood cells), PLT (platelets), and plasma. Whole blood is a complex fluid composed of these various elements, each serving crucial functions.

Red blood cells are responsible for carrying oxygen from the lungs to the rest of the body and returning carbon dioxide to the lungs. White blood cells play a key role in the immune system, defending against infection and foreign invaders. Platelets are essential for blood clotting and wound healing. Plasma, the liquid portion of blood, is a straw-colored fluid that contains water, electrolytes, proteins, hormones, and waste products.

The combination of these components allows the body to perform vital physiological functions, including transportation, regulation of body temperature, pH balance, and immune responses. Understanding these components is fundamental for veterinary assistants, as they frequently deal with blood analysis and patient care that involves monitoring these specific elements.

The option stating RBC, WBC, PLT, and serum incorrectly includes serum instead of plasma. Serum is the liquid that remains after blood has clotted and does not contain fibrinogen, which is present in plasma. This distinction is essential for proper understanding in veterinary medicine.