Final answer:
Veins are blood vessels that carry blood toward the heart. They are not under pressure from the heart. Blood in veins moves due to the action of skeletal muscles and valves in the veins.
Step-by-step explanation:
Veins are blood vessels that carry blood toward the heart. They are not under pressure from the beating heart like arteries are.
Blood in veins moves through the squeezing action of surrounding skeletal muscles, such as when you walk or breathe. Additionally, veins have valves that prevent the backflow of blood.