Veins are blood vessels located throughout your body that collect oxygen-poor blood and return it to your heart. Veins are part of your circulatory system. They work together with other blood vessels and your heart to keep your blood moving.
Veins are blood vessels located throughout your body that collect oxygen-poor blood and return it to your heart. Veins are part of your circulatory system. They work together with other blood vessels and your heart to keep your blood moving.