Thoracic Duct {Ans: begins as a dilation called the cisterna chyli located anterior to the second lumbar vertebrae (L2).}Lymphatic System {Ans: acts as a filter to protect the body from invasion of bacteria.}Spleen {Ans: this is the largest mass of lymphatic tissue.}Lymph Capillaries {Ans: what do Lymph vessels begin as?}Lymph {Ans: this is a clear, yellow, watery fluid found in the lymph vessels.}Thinner More {Ans: lymph vessels resemble the structure of veins but they have ____________ walls and _____________ valves.}