What type of fluid is lymph primarily composed of?

Lymph is primarily composed of white blood cells, particularly lymphocytes, which play a crucial role in the immune system. It also contains excess water from tissue fluid, small amounts of proteins, and waste products. The unique composition of lymph, which includes these white blood cells, is essential for the transport of nutrients, waste products, and immune responses throughout the body.

While lymph does contain some waste products, the defining characteristic of lymph is its role in immune function, highlighted by the presence of white blood cells. The fluid acts as a medium for these immune cells to travel through the body and help combat infections. The inclusion of excess water and small amounts of proteins is also significant, as they contribute to the balance of fluids in the body's tissues. Thus, the focus on white blood cells makes them a key component in understanding what lymph primarily consists of.