Lymphatic vessels are thin tubes that transport lymph, a clear fluid containing white blood cells, throughout the body. They are part of the lymphatic system, which plays a crucial role in maintaining fluid balance and supporting the immune system. These vessels collect excess fluid from tissues and return it to the bloodstream. The lymphatic vessels are equipped with one-way valves that prevent the backflow of lymph. They are found throughout the body, often accompanying blood vessels, and help filter harmful substances through lymph nodes. This process is essential for protecting the body against infections and diseases.