GCSE Biology - Blood Vessels #24

This video explores the roles of different blood vessels: arteries, capillaries, and veins. Arteries carry blood away from the heart under high pressure, requiring strong and elastic walls. Capillaries, with their thin and permeable walls, facilitate the exchange of nutrients and waste with tissues. Veins return blood to the heart at low pressure and have valves to prevent backflow. The video also explains how to calculate the rate of blood flow using a simple formula.

Explain the significance of valves in veins.

How is the rate of blood flow calculated, and what is an example?