What is the term for the fluid part of the blood?

The term for the fluid part of the blood is plasma. Plasma is a yellowish liquid that makes up about 55% of total blood volume and is composed mainly of water, along with proteins, electrolytes, nutrients, hormones, and waste products. Its primary function is to transport blood cells, nutrients, and other substances throughout the body.

In contrast, platelets are small cell fragments involved in blood clotting but do not constitute the fluid portion of blood. Clotting factors are proteins that help the blood to clot and also do not relate to the liquid aspect of blood. The term "cellular matrix" generally refers to the component of tissues that provide structural and biochemical support, not specifically to blood. Understanding plasma's role is essential in fields such as health, nutrition, and medicine, highlighting its importance in maintaining bodily functions and overall homeostasis.