🩸 Composition of Blood Blood is a specialized connective tissue that plays a central role in transport, regulation, and protection within the body. It circulates through a closed system of blood vessels and is essential for maintaining homeostasis. 🧠💧 II. Plasma (55% of blood volume) Plasma is the straw-colored fluid that remains after removal of blood cells. It is ~92% water and serves as the transport medium for nutrients,