1 a) Please label the following diagram of the respiratory system. b) Describe the role of the diaphragm in the mechanism of breathing.

1 a) Trachea, bronchi, bronchioles, alveoli,diaphragm

b) It is a muscle important in the function of respiration

On inhalation, the diaphragm CONTRACTS and FLATTENS. Air is drawn INTO the lungs (INCREASE in volume of the lungs)

On exhalation the diaphragm RELAXES and becomes DOME SHAPED. Air is forced OUT of the lungs. (DECREASE in volume of lungs)