Gas exchange

What is the main function of the respiratory system?

• To digest food

• To exchange gases

• To circulate blood

• To transport nutrients

What happens to the trachea during inhalation?

• It contracts

• It bifurcates

• It closes

• It expands

What are the small tubes that can change diameter in the respiratory system called?

• Alveoli

• Bronchioles

• Bronchi

• Trachea

What marks the beginning of the respiratory zone?

• Trachea

• Secondary bronchi

• Terminal bronchioles

• Alveolar sacs

Where does gas exchange occur in the lungs?

• In the alveoli

• In the bronchi

• In the bronchioles

• In the trachea