A question about air...

[herpguy]

recently, i learned that the atmosphere is 78% nitrogen, 21% oxygen, and 1% other stuff like carbon dioxide, sulfer dioxide, etc. I was wondering, what will happen to humans and other animals if the air was pure oxygen? Would animals die off (from ther air, not by lack of food because plants will die off), live better, or will it stay the same? If anyone knows please tell me.

[Sisyphus]

Over the short term, pure oxygen isn't harmful to animals. It can even be helpful, since breathing it means the lungs don't have to work nearly as hard, which is why they give it to smoke inhalation victims, and why people with emphysema have oxygen tanks to help them sometimes. For a prolonged period of time, however, it can cause something called oxygen toxicity, which can damage brain tissue, among other things. That wouldn't have time to happen, though, since if the atmosphere were pure oxygen, everything on earth would become incredibly flammible, and the whole planet would go up in flames pretty much immediately.

[insane_alien]

your breathing would also slow down dangerously unless you conciously kept it fast. the autonomous control of your breathing rate is controlled by the abundance of carbondioxide if there is none then it doesn't work.

[5614]

Also plants use carbon dioxide in something called photosynthesis... if the atmosphere was all oxygen then plants and trees couldn't photosynthesise and so would die.

[Mokele]

Another important point is that CO2 isn't just waste gas fo our bodies; it reacts with water in our body to form bicarbonate, which acts as a buffer to keep our acid-base balance just right. If you lose or keep too much CO2 (altitude changes, hyper/hypoventilation), you can suffer from serious and fatal imbalances in one way or the other.

 

Mokele

[Nashyboyo]

Increasing the partial pressure of atmospheric oxygen by approximately 1% would cause the whole atmosphere to be flammable. The world would explode.