Final answer:
The protein-containing fluid within lymphatic vessels is called lymph.
Step-by-step explanation:
The protein-containing fluid within lymphatic vessels is called lymph.
Lymph is the watery fluid that bathes tissues and organs and contains protective white blood cells but does not contain erythrocytes. Lymph moves about the body through the lymphatic system, which is made up of vessels, lymph ducts, lymph glands, and organs, such as tonsils, adenoids, thymus, and spleen.