1. Blood Vessel Notes

2. Arteries Carry blood away from the heart Thick walls- carry fast and furious rush of blood Elastic Very smooth- to help prevent clots Constrict and dilate based on nerve impulses No valves Aorta Pulmonary Artery

3. Arterioles Similar to arteries in function but smaller

4. Capillaries Smallest blood vessels Blood cells line up one at a time to pass through Site of gas exchange Gas exchange at a cell low in oxygen Gas exchange at the lungs

5. Venules Similar to veins in function but smaller

6. Veins Carry blood to the heart Thinner walls- carry slow and easy flow of blood Less elastic (but better able to stretch) Smooth Constrict and dilate based on nerve impulses Valves Inferior vena cava Superior vena cava Pulmonary veins

7. How do arteries and veins compare?

9. Observing blood vessels Link