6. What do the Capillaries do?
- They exchange the materials at the tissues
- Carry oxygen
- Fight disease
- Carry blood away from the heart
7. What do the Veins do?
- Pumps blood at high pressure
- Carry blood to the heart
- Fight disease
- Exchange of materials
8. Which Blood Vessel has the thickest cell wall?
- Arteries
- Capillaries
- Veins
9. What is the 'Lumen' ?
- The hole down the middle of the cell walls
- The cell walls
- Another word for the Nucleus
