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Lung anatomy

Lung anatomy

Overview

When air is inhaled through the nose or mouth, it travels down the trachea to the bronchus, where it first enters the lung. From the bronchus, air goes through the bronchi, into the even smaller bronchioles and lastly into the alveoli.

Review Date 2/3/2024

Updated by: Frank D. Brodkey, MD, FCCM, Associate Professor, Section of Pulmonary and Critical Care Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.