Arteries Veins and Capilleries

Question 1

What are arteries?

Answer 1

• ## Carries very high pressure blood from the heart to the organs in the body.

Question 2

What is the structural features of arteries?

Answer 2

• Thick Muscular walls:
• Allows them to withstand very high pressure of blood.
  Elastic Fibres:
• Stretch when the surge of blood passes through and then recoils in between surges, keeps the blood moving.

Question 3

What are capillaries/what happens in the capillaries?

Answer 3

• When blood passes through the capillaries:
• Substances e.g: Glucose and Oxygen diffuse from the blood into the cells.
• ## Co2 diffuses from the cells into the blood.

Question 4

What is the structural features of the cappilaries?

Answer 4

• Very thin walls.
• Diffusion path is very short.
• Allows substances to diffuse rapidly between the blood and body cells.

Question 5

What is a problem when blood travels to the veins?

Answer 5

• Blood travels at a slower and lower pressure.
• ## Means it could stop or go backwards.

Question 6

What is the structura features of veins?

Answer 6

• A very thin wall.
• Blood flows in low pressure so does not need to be thick.
• Many veins contains valves: Prevents backwards flow of blood.
  When blood flows in correct direction:
• Valves open to allow the blood pass through.
• Backwards- Valves shut.