Which structure divides the lungs into left and right?

Which structure divides the lungs into left and right?

• A. Pleura
• B. Alveoli
• C. Bronchi
• D. Diaphragm

Answer: (C)

The airway division from the trachea into two main bronchi creates the left and right lungs’ separation. The trachea splits into a right main bronchus and a left main bronchus, each entering its respective lung, so the bronchi establish the two-sided organization of the respiratory system. The other structures don’t perform this division: the pleura are membranes surrounding the lungs, the alveoli are the gas-exchange sacs inside the lungs, and the diaphragm is a muscle that helps drive breathing.

The airway division from the trachea into two main bronchi creates the left and right lungs’ separation. The trachea splits into a right main bronchus and a left main bronchus, each entering its respective lung, so the bronchi establish the two-sided organization of the respiratory system. The other structures don’t perform this division: the pleura are membranes surrounding the lungs, the alveoli are the gas-exchange sacs inside the lungs, and the diaphragm is a muscle that helps drive breathing.