Organisation - Blood Vessels
What is the purpose of arteries?
Transport blood away from the heart at high pressure
What features of arteries allow it to maintain high pressure?
- Narrow lumen to maintain high pressure
-Thick elastic layer so they can stretch and recoil to maintian high pressure
-Thick muscle layer ti withstand high pressure
What is the purpose of veins?
Transport blood to the heart at low pressure
What are the features of veins?
-Wide lumen to transport greater volume of blood
-Thinner muscle and elastic walls as blood at low pressure
-Valves to prevent the backflow of blood due to gravity
What is the purpose of capillaries?
Transport blood close to cells so substances can be exchanged
What are the features of capillaries?
-Narrow lumen to slow blood flow and increase diffusion time
-Thin walls, only one cell think to decrease diffusion distance
-Join small arteries and veins together