What is the main component of blood?

Plasma is the main component of blood, constituting about 55% of its volume. It is a yellowish fluid that serves multiple vital functions. Plasma is primarily composed of water, but it also contains dissolved proteins, electrolytes, nutrients, hormones, and waste products. This fluid medium plays an essential role in transporting substances throughout the body, including oxygen and carbon dioxide via red blood cells, nutrients from digestion, and waste materials for excretion.

The other components of blood, such as red blood cells, white blood cells, and platelets, make up the remaining 45% of blood volume. Red blood cells are crucial for carrying oxygen; white blood cells are involved in immune responses; and platelets play a significant role in clotting. While all these components are vital for various physiological functions, plasma is the predominant part and is integral to maintaining homeostasis by ensuring the transport and delivery systems within the circulatory system operate effectively.