What process describes the inhalation of oxygen and exhalation of carbon dioxide?

The inhalation of oxygen and exhalation of carbon dioxide is specifically referred to as external respiration. This process occurs in the lungs, where oxygen from the air is transferred into the bloodstream, and carbon dioxide is expelled from the blood into the lungs to be exhaled. It is focused on the exchange of gases between the atmosphere and the body's internal environment.

In contrast, internal respiration involves the exchange of gases at the cellular level, where oxygen is used by cells to produce energy, and carbon dioxide is generated as a waste product that then needs to be transported back to the lungs. Cellular respiration is a biochemical process that occurs within cells, utilizing oxygen to convert glucose into ATP, the energy currency of the cell. Gas diffusion refers to the passive movement of gas molecules from areas of higher concentration to areas of lower concentration, which is a fundamental physical principle that underlies the processes of external and internal respiration, but lacks the specificity of the actual physiological processes involved in breathing and gas exchange.