Question

Which statement best explains this type of blood vessel and the function of these vessels’ valves?

These are arteries, which prevent the backflow of blood because the walls have little muscle to pump blood back to the heart.
These are veins, which prevent the backflow of blood because the walls have little muscle to pump blood back to the heart.

Answer 1

The second statement best explains the type of blood vessel and the function of these vessels' valves - These are veins, which prevent the backflow of blood because the walls have little muscle to pump blood back to the heart.

Veins are large blood vessels which carry blood back to the heart. Veins have a system of valves to prevent back-flow.