Air passes from a secondary bronchus into a(n) ______.Multiple choice question.trachearespiratory bronchiolealveolustertiary bronchus

To answer the question, let's break down the choices provided:

1. Trachea: This is the windpipe that connects the larynx (voice box) to the bronchi, but it is not the next structure air passes into from a secondary bronchus.

2. Respiratory bronchiole: This branch of the bronchial tree is where gas exchange begins, but it is not the direct next step from a secondary bronchus.

3. Alveolus: This is the tiny air sac in the lungs where gas exchange occurs. Air does reach the alveolus eventually, but it's not directly from a secondary bronchus.

4. Tertiary bronchus: This is the next division of the bronchi following the secondary bronchus.

In this case, the correct answer is tertiary bronchus; air passes from a secondary bronchus into a tertiary bronchus.

Final Answer

Air passes from a secondary bronchus into a tertiary bronchus.