Veins are blood vessels that carry blood back to the heart from different parts of the body. They are part of the circulatory system and work together with the arteries to maintain blood flow.
Veins have a structure similar to flexible tubes with internal valves that help prevent the backflow of blood. Unlike arteries, veins transport darker-colored blood, as they contain less oxygen.
Veins are vital for the proper functioning of the body and allow efficient return of blood to the heart.
