What percentage of blood is composed of cells?

The correct percentage of blood that is composed of cells is approximately 45%. Blood is made up of two main components: the cellular portion, which includes red blood cells, white blood cells, and platelets, and the liquid portion known as plasma. The cellular component typically accounts for about 45% of the total blood volume, while plasma makes up the remaining 55%.

This balance plays a crucial role in various physiological functions, such as oxygen transport and immune response. Understanding this composition is essential for phlebotomy technicians, as it influences procedures like blood collection and analysis.