Question

What would happen if we had no system of lymphatic vessels, and tissue fluid was moved directly back into the circulatory system throughout the body.

Answer 1

No adaptive immune responses would occur during pathogen attack

Step-by-step explanation:

The lymphatic vessels are required in the migration of dendritic cells and to transport antigens from the interstitium of peripheral tissues to the lymph nodes, in which the T cells are activated to become effector cells. Moreover, the T (and B) effector cells move through lymph vessels to encounter those antigens presented by dendritic cells. In consequence, the lymphatic vessels have critical functions during adaptive (acquired) immune responses.