Difference Between Breathing and Cellular Respiration

Breathing vs Cellular Respiration

Though, in physiology, there is a well defined difference between breathing and cellular respiration, many people used think that respiration and breathing are two equal terms to describe the oxygen intake and carbon dioxide elimination that take place in the respiratory system. In physiology, respiration has an extensive meaning. In this article, we focus on the difference between the two steps of the respiration process namely; breathing and cellular respiration. Respiration is a basic process of life and common to all plants and animals in the world. It is mainly characterized by the utilization of food molecules to produce energy and exchange of gasses. Based on the oxygen requirement, respiration is broadly categorized into two types; (a) aerobic respiration, which requires oxygen, and (b) anaerobic respiration, which does not require oxygen.

What is Cellular Respiration?

As the name implies, the cellular respiration takes place within the cells of organisms. Hence, it is often referred to as internal respiration. Cellular respiration involved biochemical processes. In this process, food molecules are decomposed by using oxygen to form energy (ATP) which is essential for all cellular activities. While deriving energy, water and carbon dioxides are produced as by-products and carbon dioxide is expelled from the body as a waste through breathing. Because of the release of energy, cellular respiration is known as a metabolic process. Cellular respiration can be measured by taking the ratio of CO2 produced to O2 consumed. This ratio is called the respiratory quotient (RQ) and it varies based on the foodstuff consumed.

Difference Between Breathing and Cellular Respiration

What is Breathing?

Breathing is the process of exchanging O2 and CO2 between the external environment and the tissue cells. Breathing is a physical process and does not release energy, unlike the cellular respiration. The intake of air is called inhalation and expel of air is called exhalation. During the inhalation, O2 is diffused into the blood and during the exhalation, CO2, that is formed by the cellular respiration is expelled as a waste. Both cellular respiration and breathing are interrelated processes and depend on each other.

Read more: Difference Between Inhalation and Exhalation

What are the differences between Cellular Respiration and Breathing?

• Breathing is also known as external respiration as it occurs outside the cells. Cellular respiration is called internal respiration because it occurs inside the cells.

• Breathing is a physical process, whereas cellular respiration is a biochemical process.

• During the breathing, exchange of gasses (oxygen and carbon dioxide) take place. Glucose is decomposed to carbon dioxide and water during cellular respiration.

• Energy is released in cellular respiration, unlike in breathing.

• Cellular respiration requires enzymes, but breathing does not.


Images Courtesy:

  1. Aerobic Respiration by  Mikael Häggström (CC BY-SA 3.0)