Question

practice ii
what is the role of the diaphragm in breathing?
the diaphragm contracts and flattens during inhalation, increasing the volume of the chest cavity and drawing air into the lungs. the diaphragm relaxes during exhalation, decreasing the volume of the chest cavity and pushing air out of the lungs.
the diaphragm is used for speech production.
the diaphragm is a bone in the chest that helps protect the heart.
the diaphragm helps the body digest food.
the diaphragm is responsible for filtering the air during inhalation.

Explanation:

The diaphragm is a muscle. During inhalation, it contracts and flattens, increasing chest cavity volume to draw air into lungs. During exhalation, it relaxes, decreasing chest cavity volume to push air out. Speech production (related to vocal cords etc., not main breathing role), diaphragm is muscle not bone, digestion (stomach etc. organs), air - filtering (nasal cavity etc.) are incorrect.

Answer:

The diaphragm contracts and flattens during inhalation, increasing the volume of the chest cavity and drawing air into the lungs. The diaphragm relaxes during exhalation, decreasing the volume of the chest cavity and pushing air out of the lungs.