Ventilation

Question 1

What is ventilation?

Answer 1

The process of moving air into and out of the lungs

Question 2

What does moving air rely on?

Answer 2

Differences in air pressure between the lungs and the atmosphere

Question 3

Describe process of inhalation

Answer 3

1 - Diaphragm contracts
2- Intercostal muscles contract moving rib cage up and out
3 - Volume of thorax increases
4 - Air pressure in thorax falls
5 - Air pressure in thorax now less than atmospheric pressure
6 - Air moves into the lungs

Question 4

Describe process of exhalation

Answer 4

1 - Diaphragm relaxes
2 - Intercostal muscles relax moving rib cage down and in
3 - Volume of thorax decreases
4 - Air pressure in thorax rises
5 - As air pressure in thorax is now more than atmospheric pressure, air moves out of the lungs