The nurse is caring for a client at risk for a respiratory infection. Which of the following natural respiratory defense mechanisms help defend against infection? (Select all that apply).

Cilia lining the respiratory tract sweep debris upward in mucus to be swallowed.

The respiratory tract cools and dries the air being inhaled.

Cells in the respiratory tract secrete lysozymes that can destroy certain bacteria.

Macrophages engulf and destroy bacteria found in the alveoli.

High concentration of oxygen and carbon dioxide aid the defense mechanisms.