Respiratory System Flashcards
1
Q
What are the features that assist gaseous exchange?
A
- large surface area
- thin walls
- short distance for diffusion
- lots of capillaries
- large blood supply
2
Q
What is the percentage of oxygen we inspire?
A
21%
3
Q
What is the percentage of oxygen we expire?
A
16%
4
Q
What is the percentage of nitrogen in the air
A
79%
5
Q
What is the percentage of carbon dioxide we inspire?
A
0.04%
6
Q
What is the percentage of carbon dioxide we expire?
A
4%
7
Q
How is oxygen transported around the body?
A
It combines with haemoglobin to form oxyhaemoglobin
8
Q
Describe inhalation
A
- intercostal muscles contract, moving rib cage up and out
- diaphragm contracts moving down and flattering
- this causes volume of the thorax to increase and air pressure in the thorax to fall
- Air pressure in the thorax is no less than atmospheric pressure causing air to move into the lungs
9
Q
Describe exhalation
A
- intercostal muscles relax moving rip cage down and in
- diaphragm relaxes, moving up and doming
- this causes the volume of the thorax to decrease and air pressure in the thorax to rise
- Air pressure in the thorax is now more than atmospheric pressure causing air to move out of the lungs
10
Q
What is tidal volume?
A
The amount of air that enters the lungs during normal inspiration at rest
11
Q
What is a vital capacity?
A
The greatest volume of air that can be expelled from the lungs after taking the biggest possible breath
