59 Introduction to the Respiratory System

The major function of the respiratory system is to obtain oxygen and remove carbon dioxide for metabolic processes in the body. The aerobic metabolic pathway of conversion of nutrients to energy requires oxygen, for example:

C₆H₁₂O₆ + O₂ → CO₂ + ₆H₂O + energy as ATP

So, for each molecule of glucose that is converted to energy, a molecule of oxygen is needed. Because the cells require a continuous supply of ATP, the body, in turn, needs a constant intake of oxygen and method for removal of carbon dioxide. Our respiratory system functions to accomplish these necessary gas exchanges.

Respiration

(definition)

Respiration is the transport of oxygen from the air to the cell in the tissue, and the removal of carbon dioxide in the opposite direction.