Varicose veins are a form of chronic venous insufficiency, or a defect in the veins that prevents them from pumping blood properly.
These consist of two elastic flaps of tissue that alternately open and close allowing blood to flow through the valve to another vein.
These work in conjunction with the musculoskeletal system, the muscles are constantly tensing and releasing, a pattern that causes the valves to open and close as needed.
Many veins are found, especially in the lower extremities, because they have valves that act in only one direction, a tightening of the muscles results in an opening of the valves, while a relaxation of the muscles results in the closing of the valves.
Therefore, we can conclude that one of the main functions of the venous valves is to guarantee the adequate return of blood to the heart, if a return flow occurs, the blood can begin to accumulate in the veins, potentially damaging them.
Learn more about venous valves here: https://brainly.com/question/12578243