Question

which of the following is correct ?
1.the diaphragm contracts volume of chest cavity increased
2.the diaphragm contracts volume of chest cavity decreased
3.the diaphragm expands volume of chest cavity increased
4.the diaphragm expands volume of abdominal cavity decreased​

Answer 1

Answer:

option A

Explanation:

the diaphragm separates the thoracic cavity containing the heart and lungs , from the abdominal cavity and perform an important function in respiratory.

As the diaphragm contracts, the volume of thoracic cavity increases ,creating a negative pressure there,which draws air into lungs . Hence the option A is the right answer