The lymph capillaries are separate from the circulatory system They have closed ends and large pores that allow large molecules to pass through Larger molecules that are not able to pass through the capillary wall enter the lymphatic system as lymph Small valves in the vessel walls are the entry point to the lymphatic system

Lymphatic vessels are tube-like structures that carry fluid (called lymph) away from the tissues to deliver it back into the blood’s circulation. Unlike blood vessels that circulate blood in a continuous, closed-loop system, lymphatics carry fluid in one direction. The lymphatic pathway begins with lymph capillaries, the smallest type of vessel.

Summary. Lymph nodes play an essential role in the body's internal defenses against foreign bodies, removing waste from cells, and eliminating cancer cells. While typically small in size, enlarged or swollen lymph nodes can indicate a more serious condition, such as spreading cancer or lymphoma.