Question

Veins are thin walled and have valves. justify??
answer please​

Answer 1

Answer:

veins have thin walls because the blood there is no longer under pressure and they have valves to ensure blood flow in one direction.

Answer 2

Answer:

Veins have thin walls because the blood is no longer under pressure in them as they merely collect blood from the body to transport it to the heart. Valves are present in veins to ensure blood flow in one direction.