Pilot because it is thin at high altitude in non pressurized cabin.
taking oxygen in from breathing
it can be used for breathing
By breathing
Some processes that use oxygen are breathing and combustion, or burning things.
breathing
When breathing stops from lack of oxygen
Oxygen
The pathway of oxygen is like a tube or pipe in the breathing system.
By breathing oxygen, humans create more ATP so that their mitochondria do not fail.
Breathing brings oxygen into your body, where it assists in the release of ATP.
The pathway of oxygen is like a tube or pipe in the breathing system.
taking oxygen in from breathing
Breathing (sometimes breathing Smallpox)
it can be used for breathing
Oxygen
By breathing
it helps you to breath and to live of the oxygen once the breathing system takes in the oxygen and gives it to the heart