Final answer:
The clear, watery fluid in question is lymph, which is transported through the lymphatic system and filtered by lymph nodes to support immune function.
Step-by-step explanation:
The clear, watery fluid found in a network of vessels and nodes is lymph. The lymphatic system is responsible for transporting this fluid, which contains protective white blood cells, through lymphatic vessels, lymph ducts, lymph glands, and organs such as the tonsils, adenoids, thymus, and spleen.
The lymphatic system plays a crucial role in the immune system by collecting excess fluid from tissues, transporting it to the bloodstream, and filtering it through lymph nodes to remove pathogens and cellular debris. In contrast to lymph, blood contains erythrocytes (red blood cells), and bile is produced by the liver to assist in digestion, whereas saliva is a digestive fluid produced by the salivary glands.