Question

What will happen if there were no valves in the veins?

• A. The flow of blood in the veins become unidirectional.
• B. There will be backflow of blood.
• C. Oxygenated and deoxygenated blood will mix.
• D. Blood will flow under high pressure.

Answer 1

The correct option is B There will be backflow of blood.

Veins are blood vessels which bring blood from the different body parts to the heart. They are wide and hold more blood than the arteries. The blood passing through the wide lumen of veins is deoxygenated (except in pulmonary veins) and has low pressure. It flows slow and steady. Therefore, to prevent the backflow of blood, veins have valves. The valves directs the blood towards the heart and prevents it's backflow.