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: 1/8/2002 12:00:00 AM Reviewed By:A.D.A.M. Medical Illustration Team and J. Gordon Lambert, MD, Associate Medical Director; G. Eric Morgan, MS3; RxRemedy

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