What is the function of the valves in the lymphatic vessels?

1. pick up any fluid that has escaped the blood vessels

2. return the escaped fluid to the heart

3. remove any foreign material from the lymph

Explanation:

Lymph vessels pick up any fluid that has escaped the blood vessels and return it to the heart. Lymph nodes remove any foreign material from the lymph (bacteria, viruses, tumors) and contain lymphocytes (WBC!!!)

answer; i believe the answer is hydraulic action;

it would affect precipitation by causing flooding in some areas of the world due to climate increasing, causing the glaciers in the northern and southern pole of our planet to melt.

i wish you would have provided choices to simplify it and allow me to give an exact answer.