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The percentage of oxygen in air remains fairly constant on a global scale but varies considerably on a local scale. The concentration of oxygen in your lungs is much different as you inhale than when you exhale for example. The concentration of oxygen entering your car's engine is much different than the concentration in the exhaust from that same engine.
The percentage remains fairly constant on a macroscopic scale because of the equilibrium established by the uptake by plants of the carbon dioxide and subsequent release of oxygen through photosynthesis. There is also a substantial amount of oxygen dissolved into the oceans of the Earth which remains in equilibrium with the oxygen in the air. Just based on the scale, it would take an enormous amount of oxygen addition or removal from the atmosphere to make a significant change in the percentage of oxygen in the atmosphere. Such a change would take a very long time to accomplish. In truth, the composition of the atmosphere millions of years ago was different than now - with noticeably higher levels at times and lower levels at other times. It took millions of years for the changes to occur however.
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Where does the oxygen produced in photosynthesis go?
The oxygen that is produced in photosynthesis goes into the air.
Do oxygen in the air you breathe comes from green plants?
When plants go through photosynthesis, they release oxygen into the air. Any plant, including greens, that go through photosynthesis produce oxygen. The oxygen that is produced, we use it.
When air cools air?
it will go down
What is the direction of warm air and cold air?
cold air go up hot air go down.
Why does carbons mass go down when it is burned in oxygen?
fire
Why is it harder to breathe he higher you go?
Because - the higher up the atmosphere you go - the less oxygen is in the air you breathe. Our bodies need a certain percentage of the air we breathe to be Oxygen - reduce the amount of oxygen in each breath, and it soon affects the body.
Why air pressure is low at the top and why there is less oxygen at height?
Air has weight. The weight of all the air above pushes down, squeezing on the lower levels. Think of a column of air seven miles high, pressing down on air at ground level. We call this pressing down force " air pressure ". The amount of oxygen in the atmosphere is close to the same whether you are at 30,000 feet or down at sea level, the difference is the pressure. Humans get oxygen into their blood by breathing air into our lungs where air pressure forces it into our blood. When you go up to very high altitudes, the oxygen is still there, but there is not enough pressure to force it into our blood and we would suffer from 'hypoxia', or, a lack of oxygen.
What does the level of dissolved oxygen go down after sunset?
Why does the level of dissolved oxygen go down after sunset? because it gets colder.
Where does the oxygen produced in photosynthesis go?
The oxygen that is produced in photosynthesis goes into the air.
Do oxygen in the air you breathe comes from green plants?
When plants go through photosynthesis, they release oxygen into the air. Any plant, including greens, that go through photosynthesis produce oxygen. The oxygen that is produced, we use it.
What is the path of a frog's respiratory system starting with air?
The frogs' chin goes down, pulling air into the vocal sac. Then, it's nostrils shut and the chin goes up, forcing the air into the lungs. When they oxygen is taken, the chin will go down, pulling the air our of the lungs. Then the nostrils open up, and the chin will go up, pushing the air our of the chin. Then repeats.
When air cools air?
it will go down
Would you please use 'oxygen' in a sentence?
Oxygen is what you breathe. only 20% of the air is oxygen. there ya go!
Does hot air go up or down?
It can go up when hot air is filled and can come down by reducing the hot air.
Where does oxygen go once it gets into the lungs?
the oxygen goes to the air sacs inside of the lungs.
Where does oxygen go after its in your mouth?
After the mouth (or nose), oxygen (as part of the air) goes down your trachea, into the bronchi, and through the bronchioli, into the alveoli, where it enters the blood and gets taken via the blood to the various parts of your body.
Why do metals go rusty?
They react (oxidise) with the oxygen in the air.
