blood vessels

Question 1

what do valves do

Answer 1

prevent back flow

Question 2

arteries

Answer 2

carry blood away from the heart
carry blood at high pressure
arteries do not have values
they have thick and elastic walls

Question 3

veins

Answer 3

carry deoxygenated blood 
take blood to the heart 
carry blood at low pressure 
do have valves
they have thin layer of muscle tissue

Question 4

capillaries

Answer 4

occur in large quantities around the muscles
they are 1cm thick
allow gaseous exchange to take place

Question 5

where does gaseous exchange take place

Answer 5

blood at the lungs/ alveoli

Question 6

blood arriving in alviel has what

Answer 6

carbon dioxide

Question 7

blood in alveoli has what

Answer 7

oxygen

Question 8

where does blood move from alveoli

Answer 8

away

Question 9

what happens at inspiration

Answer 9

Diaphragm and intercostal contract.
Diaphragm moves down, rib cage moves up and out.
Volume inside the chest cavity increases.
The pressure decreases. Rushes in.

Question 10

what happens at expiration

Answer 10

Diaphragm and intercostal relax.
Diaphragm moves up, rib cage moves in and down.
Volume inside the chest cavity decreases.
The pressure increases. Goes out.