Do we breathe oxygen or air?

The air we breathe is made up of several gases. Oxygen is the most important for keeping us alive because body cells need it for energy and growth. Without oxygen, the body's cells would die. read more

We cannot breathe in pure oxygen because in air only 20.95% of oxygen is present . And in air we breathe easily without any resistance. By this percentage of oxygen in air shows that we cannot breathe in 100 % of oxygen. It's causes the death of a person. read more

Our blood has evolved to capture the oxygen we breathe in and bind it safely to the transport molecule called haemoglobin. If you breathe air with a much higher than normal O2 concentration, the oxygen in the lungs overwhelms the blood's ability to carry it away. read more

The nitrogen concentration in the blood and the alveolar air is about the same. The gases exchange across the alveolar wall and the air inside the alveoli becomes depleted of oxygen and rich in carbon dioxide. When you exhale, you breathe out this carbon dioxide enriched, oxygen-poor air. read more