Blood Vessels

Question 1

What are the advantages of specialized blood vessels?

Answer 1

1. Allows blood to be carried at different pressures
2. Ensures de/oxygenated blood are separated.
3. Facilitates exchange of substances between tissues and the bloodstream

Question 2

In what 4 main ways are blood vessels different?

Answer 2

1. Different size lumen + thickness of smooth muscle & elastic fibres = establishes blood pressures.
2. Pres/absence of valves maintains unidirectional blood flow (prevents backflow)
3. Direction of travel and the type of blood transported.

Question 3

What are the three blood vessels of the body?

Answer 3

1. Arteries
2. Veins
3. Capillaries.

Question 4

Describe the features, functions and adaptations of arteries.

Answer 4

1. Carries blood away from the heart at a high blood pressure
2. Small lumen and walls have thick layers of smooth muscle and elastic tissue to ensure they can stretch and recoil and maintain a high BP
3. No valves.

Question 5

Describe the features, functions and adaptations of veins.

Answer 5

1. Carries blood towards the heart at a low blood pressure.
2. Relatively thin walls b/c they do not need to be strong - thin layers of smooth muscle and elastic fibres
3. Big(gest) lumen to allow blood to flow with little resistance.
4. Have valves to prevent backflow

Question 6

Describe the features, functions and adaptations of capillaries.

Answer 6

1. Exhanges oxygen and nutrients with tissues and cells + takes away waste products.
2. Carries blood through organs at a very low BP.
3. Have single-cell thick permeable walls to ensure a short diffusion distance and efficient exchange.
4. Lumen is much wider than walls.