Blood vessels

Question 1

3 types of blood vessels

Answer 1

1. Arteries
2. Capillaries
3. Veins

Question 2

What do arteries do
Describe structure of artery

Answer 2

Carry blood under high pressure
Artery walls are strong, thick & elastic
Walls are thick compared to midde (lumen)
Thick layers of muscle
Can stretch and then spring back

Question 3

What are capillaries
Describe structure (at least 3 points)
What do they do (at least 2 points )

Answer 3

Really small vessels - tiny
One cell thick
Very small lumen
Arteries branch into capillaries
Permeable walls - substances can diffuse
Supply food & oxygen
Take away Co2
Walls 1 cell thick, increases rate of diffusion by decreasing distance over which it occurs

Question 4

What do veins do
Describe structure ( at least 3 points)

Answer 4

Capillaries join up to form vein
Blood at lower pressure
Walls not as thick as arteries
Bigger lumen than artery (help blood flow)
Valves to help blood flow in right direction

Question 5

How do you calculate rate of blood flow

Answer 5

Rate if blood flow= volume of blood /number of mins
Eg 1464 ml of blood through artery in 4.5 minutes :
Blood flow = 1464/4.5 = 325 ml/min