Give some differences between Arteries, Capillaries and Veins.
Please help me to solve it. Thank you.

Dear Student,

Arteries: 

• Carry Oxygen rich blood from heart to all parts of the body except pulmonary artery
• Since blood flow is rapid and at high pressure they have thick elastic walls.
• Valves are absent.

Veins: 

• Carry carbon dioxide rich blood from all parts of the body back to the heart except pilmonary vein.
• They have thin walls
• Valves present to prevent back flow of blood.

Capillaries:

• Capillaries act as a link between arteries and veins.
• Consists of just a single layer of endothelial cells.
• Water and other small-molecule substances can pass through this wall.
• No valves can be found