1. What is the function of valves?
- Prevent carbon dioxide diffusing into tissues
- To prevent backflow
- Ensure all oxygen diffuses from the blood
- Ensure the blood is flowing very fast
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Other questions in this quiz
2. Why do capillaries in the brain have tight junctions?
- To prevent fluid on the brain
- Prevent the drainage of brain fluid
- To prevent essential minerals diffusing into the capillaries
- Ensure that oxygen does not diffuse back into the capillaries
3. What is the blood pressure in the veins?
- Very low
- Very high
- Greater than the arteries
4. What do artery walls contain?
- Collagen and elastic fibres only
- Elastic fibres, smooth muscle and collagen
- Elastic fibres and smooth muscle only
- Elastic fibres and collagen only
5. What is the function of arterioles?
- Link capillaries and veins
- Constrict and dilate to control blood flow to individual organs
- Remove tissue fluid
- Prevent the diffusion of excess water