External vs Internal Respiration: Difference and Comparison

Science is a miracle subject not because it does any miracle but because it provides the reasoning behind each and everything that happens all across the globe. One such common activity is respiration.

Many people know the meaning of the given term, but very few know the exact thing it stands for. 

External Respiration and Internal Respiration are two such parts of respiration in living organisms which are many times used interchangeably and at each other’s place.

But it is important to know that while these two sound really similar, there are a ton of differences that lie between these two, upon which this article shall shed some light. 

Key Takeaways

1. External respiration refers to exchanging oxygen and carbon dioxide between the lungs and the environment, while internal respiration occurs at the cellular level within tissues.
2. External respiration requires the respiratory system, including the lungs and airways, while internal respiration relies on the circulatory system and cellular metabolism.
3. Both processes are crucial for maintaining proper oxygen and carbon dioxide levels to support healthy functioning.

External Respiration vs Internal Respiration 

The difference between External Respiration and Internal Respiration is that the former term, as its name itself suggests, refers to the activity of respiration between external phenomena and the body, while on the contrary, Internal Respiration refers to the respiration that takes place between the internal cells of the body only. Apart from this, there are many other differences laying between these two processes that make these different from one another. 

External Respiration, as the name itself suggests, occurs when external circumstances are involved. In simple words, this happens to be a very crucial activity undertaken by the body in which oxygen is inhaled and carbon dioxide is exhaled.

Not only this, but this respiration also occurs between the blood cells and the lungs. It includes the exchange of gases like oxygen and carbon dioxide. 

On the contrary, Internal Respiration, as suggested by the name itself, refers to the process in which respiration occurs inside the body without the involvement of the external environment or features.

Another term for this process is cellular respiration because it takes place inside the cells only.  

Comparison Table 

Parameters of Comparison	External Respiration	Internal Respiration
Meaning	This happens to be a very crucial activity undertaken by the body in which oxygen is inhaled, and carbon dioxide is exhaled. In this process, breathing and gas exchange takes place.	Refers to the process in which respiration occurs inside of the body without the involvement of the external environment or features.
Nature	It is a mechanical process looking at its nature.	It is a chemical process looking at its nature.
Occurs between	It occurs between the external environment and the body.	It involves no external interference and occurs inside of the body only.
Main action	The most crucial action is the exchange of oxygen and carbon dioxide.	The most crucial action happens to be the segregation of molecules to produce energy that is consumed by the cells.
Involves	The external environment, lungs, and mouth	Cells of the body
End result	It produces gas exchange only.	It produces energy along with gas exchange.
Voluntariness	It can be both voluntary or involuntary.	It has to be an involuntary process only.

What is External Respiration? 

External Respiration is a term of science given to a process performed by a body in which it derives pure and clean oxygen from the environment and surroundings and uses this oxygen for cellular respiration.

Not only this but in this process, polluted carbon dioxide is thrown away from the body to keep the body keep and off any pollutants. 

But it does not end here and involves the exchange of gases between the lungs and the blood particles. During this exchange, the inhaled oxygen, which is purely transported into the blood all over the body, and the polluting carbon dioxide from the body is transported to the lungs.

After receiving it, the lungs exhale this and make the body pollution-free. This exchange keeps taking place unless a balance is maintained. 

As per its nature, it happens to be a rather mechanical process because of the whole mechanism dedicated to it. And it is a voluntary process as well as an involuntary process depending on the situation.  

What is Internal Respiration? 

Internal Respiration, also referred to as Cellular Respiration, is another form of respiration that takes place in the body of living organisms, especially humans. Now, as the name itself suggests, it refers to a process that occurs inside the body without involving any external features. 

But in reality, this process is just a co-related step in the process of External Respiration because the oxygen that is derived during external respiration gets utilized in internal respiration.

This establishes an inseparable bond between the two processes.  

What happens in this process is that the oxygen inhaled gets transported to the blood, and then an exchange of gases happens between the blood and the cells.

After the oxygen reaches cells, they break down this gas into tiny molecules to make the release of ATP possible. This ATP happens to be the energy of the cells. 

By nature, this is an involuntary and chemical process that involves no external interference and occurs inside the body only. Oxygen happens to be a very crucial element in this process too. 

Main Differences Between External and Internal Respiration 

1. External Respiration is a process that happens to be a very crucial activity undertaken by the body in which oxygen is inhaled, and carbon dioxide is exhaled. In this process, breathing and gas exchange takes place. While on the other side, Internal Respiration refers to the process in which respiration occurs inside the body without the involvement of the external environment or features. 
2. External Respiration is a mechanical process looking at its nature. While on the other side, Internal Respiration is a chemical process looking at its nature. 
3. External Respiration occurs between the external environment and the body. While on the other side, Internal Respiration involves no external interference and occurs inside the body only. 
4. In External Respiration, the most crucial action is the exchange of oxygen and carbon dioxide. While in Internal Respiration, the most crucial action happens to be the segregation of molecules to produce energy that is consumed by the cells. 
5. External Respiration can be both voluntary and involuntary. While on the other side, Internal Respiration has to be an involuntary process only. 

References

1. https://www.atsjournals.org/doi/abs/10.1164/arrd.1984.129.2P2.S21
2. https://www.sciencedirect.com/science/article/pii/0025556468900813