What are the three distinct types of blood vessels? Describe each in few sentences?
Arteries - carry high pressure blood away from the heart. Have thick walls and a small lumen in relation to the thickness of their walls. Veins - carry lower pressure blood towards the heart. They have thin walls and a wide lumen in relation to the thickness of their walls. They also have valves to prevent the back flow of blood. Capillaries - have one cell thick walls to allow substances to diffuse in and out of the blood. Their function is substance exchange, removing waste products from cells and supplying them with glucose, oxygen, mineral ions etc.
Get an answer in 5 minutes from expert tutors at Oxford, Cambridge, Imperial and more.