Difference Between External and Internal Respiration: An Overview
Our body carries out two types of respiratory activities – external respiration and internal respiration. These are two distinct processes that are essential for our body to function properly. In this article, we will discuss the key differences between these two types of respiration.
External Respiration
External respiration is the process of exchanging gases between the lungs and the outside environment. In simple terms, it refers to the process of breathing, during which we inhale oxygen and exhale carbon dioxide. External respiration involves the following steps:
1. Inhalation: When we breathe in, the air enters our nose or mouth and travels down the trachea into the lungs.
2. Gas exchange: Once the air reaches the lungs, it passes through bronchioles into tiny air sacs called alveoli. Here, the oxygen from the air diffuses into the blood vessels surrounding the alveoli, while the carbon dioxide from the blood diffuses into the alveoli.
3. Exhalation: After the gas exchange, we breathe out, and the carbon dioxide is expelled from our body, completing the process of external respiration.
Internal Respiration
Internal respiration, on the other hand, refers to the process of exchanging gases between the blood and the body’s tissues. It involves the following steps:
1. Oxygen transport: The oxygen-rich blood from the lungs is carried to the body’s tissues by the circulatory system.
2. Gas exchange: In the tissues, the oxygen is released from the blood and diffuses into the cells, while the carbon dioxide produced by the cells diffuses into the blood.
3. Carbon dioxide transport: The carbon dioxide-rich blood is then transported back to the lungs for elimination via the process of external respiration.
Key Differences
The main differences between external and internal respiration are:
1. Location: External respiration occurs in the lungs, while internal respiration occurs in the body’s tissues.
2. Gas Exchange: In external respiration, the exchange of gases occurs between the lungs and the outside environment, while in internal respiration, it occurs between the blood and the body’s tissues.
3. Purpose: External respiration is necessary to provide the body with oxygen and eliminate carbon dioxide, while internal respiration is necessary to supply tissues with oxygen and remove carbon dioxide.
4. Process: External respiration involves breathing, while internal respiration involves the transport and exchange of gases between the blood and the tissues.
In conclusion, external and internal respiration are two distinct but interdependent processes that play a crucial role in maintaining the body’s overall health and functioning. Understanding the difference between the two is important to appreciate how our body operates and ensures the delivery of oxygen to the tissues that need it.
Table difference between external and internal respiration
| External Respiration | Internal Respiration |
|---|---|
| Refers to the exchange of gases between the lungs and the blood in the respiratory system | Refers to the exchange of gases between the blood and the tissues throughout the body |
| Oxygen is taken in and carbon dioxide is released | Oxygen is released from hemoglobin in red blood cells and carbon dioxide is absorbed into the blood |
| Occurs in the alveoli in the lungs | Occurs in the capillaries surrounding the tissues |
| Helps to oxygenate the blood and remove carbon dioxide | Helps to deliver oxygen to and remove carbon dioxide from the body’s cells |
| Considered an external process | Considered an internal process |