Respiratory System Anatomy – Major Zones & Divisions

Author: Scott A. Sheffield MS

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Functionally, the respiratory system is separated into a conducting zone and respiratory zone.

The respiratory zone of the respiratory system
The conducting zone of the respiratory system labeled and highlighted
The conducting zone.
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Need a hand learning the anatomy of the respiratory system? Check out these free respiratory system quizzes and labeled diagrams.

  • The image descriptionrespiratory zone is found deep inside the lungs and is made up of the respiratory bronchioles, alveolar ducts, and alveoli. These thin-walled structures allow inhaled oxygen (O2) to diffuse into the lung capillaries in exchange for carbon dioxide (CO2).
The respiratory zone of the respiratory system
The respiratory zone of the respiratory system with the respiratory bronchiole, alveolar duct and alveoli labeled.
The respiratory zone.
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Anatomically, the same structures are often divided into the upper and lower respiratory tracts.

  • The image descriptionupper respiratory tract structures are found in the head and neck and consist of the nose, pharynx, and larynx.
The upper respiratory tract of the respiratory system
The upper respiratory tract of the respiratory system with the nose, pharynx and larynx labeled.
The upper respiratory tract
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  • The image descriptionlower respiratory tract structures are located in the thorax or chest and include the trachea, bronchi, and lungs (= bronchioles, alveolar ducts, and alveoli).
The lower respiratory tract of the respiratory system
The lower respiratory tract of the respiratory system labeled and highlighted
The lower respiratory tract
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Please note that many authorities include the larynx with the lower respiratory tract structures.

An Overview of the Major Zones and Divisions of the Respiratory System:

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