1.7 Flashcards
1
Q
- What kind of blood do arteries carry?
A
- Deoxygenated blood from heart to the lungs
2
Q
- What arteries are the exception and don´t carry oxygenated blood?
A
- Pulmonary artery and umbilical artery
3
Q
- Why do arteries have a small lumen?
A
- To maintain a high pressure.
4
Q
- Why do arteries have elastic fibres?
A
- So that walls can expand and recoil, and therefore maintain a high pressure.
5
Q
- Do veins have a large lumen or a small lumen, explain your answer.
A
- Large lumen, because it carries low pressure blood so therefore a large lumen gives less resistance.
6
Q
- What are valves used for?
A
- To prevent backflow of blood that could be caused by the low pressure.
7
Q
- Veins have thin walls to…
A
- Allow skeletal muscles to squeeze the veins and therefore return blood to the heart.
8
Q
- What is the function of the pulmonary vein?
A
- To carry oxygenated blood from lungs back to the heart for circulation around the body.
9
Q
- Why are capillaries 1 cell thick?
A
- For a fast diffusion rate (which is affected by distance)
10
Q
- What important process happens in the capillaries?
A
- Gas exchange.
11
Q
- Why do capillaries have permeable walls?
A
- So that white blood cells can escape to kill infections.
