Across
- 4. produce an unidirectional flow where air enters and exits the lung at the same time
- 6. more oxygen is available to diffuse into the blood
- 7. exchanges oxygen and carbon dioxide between the gas and blood
Down
- 1. moving the respiratory gases from the upper system to the organs
- 2. produces sounds without the vocal folds of mammals
- 3. a respiratory valve that protects the airway,lacks sound producing vocal folds
- 5. filter air that birds breathe