Unit 2: Functional Diagnostics and Imaging Techniques

2.3 Pneumology



Section 1: Introduction to Pneumology


  • What are the main functions of the respiratory system?



During inhalation, air containing a high concentration of oxygen enters the lungs through the airways. At the same time, blood is returning to the lungs with high carbon dioxide and low oxygen levels. In the pulmonary capillaries, carbon dioxide is exchanged for oxygen from the alveoli. Blood then leaves the lungs with a high oxygen content and a relatively low carbon dioxide content to be distributed to the tissues of the body by the left side of the heart. During exhalation, gas with a high concentration of carbon dioxide is expelled from the body.

blood flow

Figure 2: The alveolus is a sac which allows gas exchange of oxygen and carbon dioxide by diffusion.
The alveoli have thin walls to aid this diffusion.
Source: MAMMOTHMEMORY; the pulmonary system.