Final answer:
The fluid that is part of the lymphatic system is known as lymph (c), which is crucial for transporting white blood cells and maintaining fluid balance by returning interstitial fluid to the bloodstream.
Step-by-step explanation:
The lymphatic system includes lymphatic vessels, lymphoid organs, and a fluid known as lymph (c). Lymph is the fluid that carries white blood cells and bathes tissues and organs, but unlike blood, it does not contain red blood cells (erythrocytes). The system transports the lymph throughout the body, helping to remove interstitial fluid from tissues, transport dietary lipids and immune cells, and filter pathogens from the blood.
Every day, approximately 20 liters of plasma filter into the interstitial spaces due to capillary filtration. While a majority of this fluid is reabsorbed directly by blood vessels, about three liters per day are absorbed by the lymphatic capillaries as interstitial fluid. Once inside the lymphatic system, this fluid is referred to as lymph. The lymphatic system plays a crucial role in returning this fluid to the bloodstream and is integral in immune function. If the system is damaged, it can result in lymphedema, an accumulation of protein-rich interstitial fluid in tissue spaces.