The term for the fluid portion of blood that carries cells and nutrients is plasma. Plasma is a pale yellow liquid that constitutes about 55% of total blood volume. It contains water, electrolytes, proteins, hormones, and waste products, facilitating the transport of vital substances throughout the body. Plasma plays essential roles in maintaining homeostasis, regulating blood pressure, and serving as a medium for exchanging nutrients and waste between blood and tissues. Additionally, it contains proteins that are critical for blood clotting and immune responses.