Valves in veins are bicuspid, meaning they have two flap-like structures that regulate blood flow. These flaps are made of elastic tissue. The valves’ main job is to keep the blood moving in one direction – back up towards the heart. When the valve is open, blood freely flows upward towards the heart; when the valves are closed, blood cannot flow back towards the legs. The deep veins carry 90% or more of the blood from the legs toward the heart.
https://www.usaveinclinics.com/blog/what-are-vein-valves/
Загруженный контент будет перемещен в новый альбом Вы должны создать аккаунт или войти, если хотите отредактировать этот альбом позже.