Breathing

Question 1

When breathing in what happens in the lungs?

Answer 1

The diaphragm contracts and flattens
The intercostal muscles contract, pulling the rib cage up and out
The volume the chest cavity increases
This causes the air pressure in the chest cavity and lungs to decrease
The air pressure in the lungs is no lower than the atmospheric air pressure
Air is drawn into the lungs from higher pressure outside to lower pressure inside.

Question 2

What happens in the lungs when you breath out?

Answer 2

The diaphragm relaxes and domes up
The intercostal muscles relax and the rib cage moves down and in
The volume the chest cavity decreases
This causes the air pressure in the chest cavity and lungs to increase
The air pressure in the lungs is now higher than the atmospheric air pressure
Air is forces out of the lungs from higher pressure inside to lower pressure outside.

Question 3

How do the lungs increase the surface area without increasing size very much?

Answer 3

Instead of one large balloon, the lungs are divided up into hundreds of small balloons called alveoli. This increases the surface area: volume ratio and increase the rate of gas exchange.

Question 4

Main substances in cigarettes?

Answer 4

Nicotine
Carbon monoxide
Tar
Ammonia

Question 5

What is gas exchange?

Answer 5

It is getting the gases to move into or out of the blood.

Question 6

What is Asthma?

Answer 6

It develops when the bronchial tubes become swollen and the muscles around the tubes contract to make the tubes narrow.

Question 7

What 3 things does the alveoli depend on when doing gas exchange

Answer 7

1. Large surface area
2. short distance
3. Diffusion gradient