respiratory system(gas exchange)

Question 1

why does GE occur?

Answer 1

• to allow O2 to enter blood supply and be delivered to the cells to be used in the process of CR
• it allows CO2 to leave the body by transferring it from blood into the alveoli.

Question 2

Where does GE occur?

Answer 2

between the alveoli and the surrounding capillaries

Question 3

What is GE?

Answer 3

the exchange of O2 and CO2 into the lungs.
O2 moves into the lungs to be delivered to cells, while CO2 moves out of the lungs to be breathed out

Question 4

When does GE ocurr?

Answer 4

all the time, unless alveoli are damaged by respiratory conditions

Question 5

Explain the process of GE

Answer 5

blood capillaries surrounding alveoli brough to lungs by pulmonary arteries, blood has been taken through capillaries of the body where much 02 has been used up by cells= low conc of O2 in blood, lower than conc in the alveolus.

02 dissovles in moisture on inside of alveolus and diffuses through membrane, through walls of capillaries into blood.

blood arriving at capillaries of alveolus has been through the body, where is has picked up a high conc of CO2 produced by CR. conc in CO2 is higher in capillaries than alveolus
CO2 diffuses into alveolus to be exhaled.

Question 6

Explain the structure of GE

Answer 6

-alveoli give lungs huge SA, so large amounts of gases can be exchanged
- each alveolus well supplied with blood vessels, so that much blood as possible is close to alveolus, so gases dont have to travel far.
- membrane forming wall in alveolus is thin, so gases dont have to travel far
- lungs are deep in the chest cavity, preventing excess evaporation of fluid covering the respiratory system.
- lung volume can be changed by movements of respiratory muscles so air can flow in and out,

Question 7

What is the inspired and expired air % of CO2 and O2 during gas exchange

Answer 7

inspired 02= 20.95%
inspired CO2= 0.04%

Expired O2= 15.80%
expired CO2= 4.30%