Difference Between Ventilation and Respiration

Main Difference – Ventilation vs Respiration

Ventilation and respiration are two processes that are involved in supplying oxygen to the body. The main difference between ventilation and respiration is that ventilation is the provision of fresh air into the lungs while respiration is the gas exchange between the body and the external environment. Lungs are the organs involved in both ventilation and respiration of most vertebrates. Breathing occurs through inhalation in animals. Lungs provide close contact between blood and atmospheric air, facilitating respiration.

Key Areas Covered

1. What is Ventilation
      – Definition, Process, Role
2. What is Respiration
      – Definition, Process, Role
3. What are the Similarities Between Ventilation and Respiration
      – Outline of Common Features
4. What is the Difference Between Ventilation and Respiration
      – Comparison of Key Differences

Key Terms: Carbon Dioxide, Expiration, External Respiration, Inspiration, Internal Respiration, Oxygen, Respiration, Ventilation

What is Ventilation

Ventilation is the provision of fresh air into the lungs. The conducting zones of the lungs are involved in ventilation. It includes nose, pharynx, larynx, trachea, primary bronchi, bronchial tree, and terminal bronchioles. Inspiration and expiration are the two events of ventilation. Inspiration and expiration are shown in figure 1.

Figure 1: Inspiration and Expiration

Both inspiration and expiration occur based on the pressure differences between the atmosphere and the lungs. Inspiration occurs when the pressure inside the lungs goes down. The atmospheric pressure is 760 mm Hg. The increased volume of the lungs causes the reduction of pressure. It is achieved by the contraction of the diaphragm and intercostal muscles. When the pressure goes down to 758 mm Hg, the atmospheric air comes into the lung. This is called inspiration. Once the diaphragm and intercostal muscles are relaxed, the space inside the lungs is reduced, forcing the air out of the lungs. This is called expiration.   

What is Respiration

Respiration refers to the gas exchange between the body and the external environment. It occurs by diffusion based on the partial pressure differences of the respiratory gases – oxygen and carbon dioxide. The internal and and external respiration are the two types of respiration in the body. External respiration occurs in the alveoli of the lungs. When compared to the air in the alveoli, the partial pressure of oxygen is less, and the partial pressure of carbon dioxide is high in the blood. Therefore, oxygen from the atmospheric air diffuses into the blood while carbon dioxide in the blood diffuses into the air in the alveoli. Oxygen External respiration is shown in figure 2.

Figure 2: External Respiration

Internal respiration occurs in metabolizing tissues. Oxygen is transported by the red blood cells to the tissues. The partial pressure of oxygen is low inside the tissue while that of the carbon dioxide is high when compared to the blood. Therefore, oxygen diffuses into the tissue and carbon dioxide diffuses into the blood. 

Similarities Between Ventilation and Respiration

• Both ventilation and respiration are two events involved in taking oxygen into the body.
• Both ventilation and respiration occur in lungs of most vertebrates.

Difference Between Ventilation and Respiration

Definition

Ventilation: Ventilation refers to the provision of fresh air into the lungs.

Respiration: Respiration refers to the gas exchange between the body and the external environment.

Consequence

Ventilation: Ventilation is the first event of respiration.

Respiration: Respiration is the taking up of oxygen by the red blood cells.

Significance

Ventilation: Ventilation is breathing, which takes air into the lungs.

Respiration: Respiration is the exchange of oxygen and carbon dioxide between blood and the atmospheric air.

Occurrence

Ventilation: Ventilation is carried out by lungs.

Respiration: Respiration occurs in the alveoli and walls of blood capillaries.

Gases

Ventilation: All gases in the atmospheric air are taken into the lungs during ventilation.

Respiration: Oxygen and carbon dioxide are involved in the respiration.

Physical/Chemical Process

Ventilation: Ventilation is a physical process.

Respiration: Respiration is a chemical process.

Voluntary/Involuntary Action

Ventilation: Ventilation is a voluntary action.

Respiration: Respiration is an involuntary action.

Events

Ventilation: Inspiration and expiration are the two events of ventilation.

Respiration: Internal and external respiration are the two events of respiration.

Base

Ventilation: Ventilation occurs based on the pressure differences of air between lungs and the atmosphere.

Respiration: Respiration occurs based on the partial pressure differences of respiratory gases between blood and the atmospheric air or tissues.

Conclusion

Ventilation and respiration are two processes involved in taking in oxygen into the body. Ventilation is carried out by the lungs while respiration occurs between the alveoli and blood. Atmospheric air is taken into the lungs during ventilation. Oxygen and carbon dioxide are exchanged during respiration. The main difference between ventilation and respiration is the role of each process in obtaining oxygen.   

Reference:

“What is ventilation? | AIVC.” AIVC – Air Infiltration and Ventilation Centre, Available here.
“Gas exchange.” Health Video: MedlinePlus Medical Encyclopedia, Available here.

Image Courtesy:

1. “2316 Inspiration and Expiration” By OpenStax College – Anatomy & Physiology, Connexions Web site. Available here, Jun 19, 2013 (CC BY 3.0) via Commons Wikimedia
2. “Alveoli” By helix84 – en:Image:Alveoli.jpg (CC BY 2.5) via Commons Wikimedia