Understanding Why We Breathe In Oxygen Though Air is Mostly Nitrogen

Have you ever wondered why we are often told to breathe in oxygen when we know that air is mainly composed of nitrogen? This article aims to clarify the distinction and shed light on the crucial role of oxygen in human respiration.

The Composition of Air

Air is not just a simple mix of oxygen and nitrogen; it is a complex gas composition, with nitrogen making up about 78% and oxygen about 21%. The remaining 1% consists of trace gases such as argon, carbon dioxide, and water vapor.

When people say we breathe in oxygen, they mean that oxygen is the gas we use for energy production and aerobic respiration. Here is a detailed breakdown of why this statement is accurate and why nitrogen, despite being a significant part of the air we breathe, does not play a role in our breathing processes.

The Crucial Role of Oxygen

Oxygen's Role in Cellular Respiration: Oxygen is essential for aerobic respiration, the primary method by which our cells generate energy. In this process, glucose is metabolized with the help of oxygen to produce energy, carbon dioxide, and water. This reaction can be simplified as:

Glucose Oxygen → Carbon Dioxide Water Energy

The Inert Nature of Nitrogen

Nitrogen's Inert Nature: Nitrogen, comprising about 79% of every breath we take, is largely inert and does not participate in the metabolic processes that occur in our bodies. Consequently, when we breathe in nitrogen, it is not consumed or chemically altered by the body.

Breathing and Gas Exchange: When we inhale, our respiratory system takes in a mixture of gases, including both oxygen and nitrogen. However, our bodies selectively use only the oxygen for energy production, and the rest, including nitrogen and carbon dioxide, are exhaled. This selective use and emission of gases is facilitated by the lungs and bloodstream.

The lungs and bloodstream facilitate the exchange of crucial gases, allowing oxygen to be absorbed into the blood while carbon dioxide is expelled when we exhale.

The Mechanism of Breathing

Respiratory Mechanism: Our respiratory system, including nostrils, trachea, lungs, and diaphragm, works together to enable us to breathe. Although we breathe in nitrogen-rich air, our body efficiently separates the needed oxygen from the nitrogen and other gases.

Fortunately, our lungs can separate and utilize as much oxygen as necessary, binding it chemically into our blood, while the excess nitrogen and other gases are expelled with the carbon dioxide and water vapor during exhalation.

Conclusion

In conclusion, while we do inhale and exhale air that is rich in nitrogen, the emphasis on oxygen in discussions about respiration is justified due to its critical role in energy production. Understanding the composition of air and the selective use of gases by our bodies is important for comprehending the intricate processes of respiration and maintaining overall health.