Question

Which of the following is correct
i) the diaphragm contracts - volume of chest cavity increased
ii) the diaphragm contracts - volume of chest cavity decreased
iii) the diaphragm expands - volume of chest cavity increased
iv) the diaphragm expands - volume of che st cavity decreased

a) i
b) i & ii
c) ii & iii
d) iv

Answer 1

Answer - Option - A. (i)

When the diaphragm contracts - volume of chest cavity increased.

Extra Information :-

What is Thoracic Diaphragm :-

• The diaphragm is the dome-shaped muscular organ which serves as the main muscle of respiration and plays an important role in the process of breathing.

• Diaphragm separates the thoracic cavity from the abdominal cavity.

What is Thoracic cavity :-

• Thoracic cavity, also known as chest cavity and is separated from the abdomenal cavity by the diaphragm.

• It is surrounded by the ribs, the vertebral column and the sternum.

• There are two openings of thoracic cavity - thoracic inlet and thoracic outlet.

During Inhale :-

• Diaphragm contracts and flattens
• Volume of the thoracic cavity increased
• Pressure in the lungs decreased, and air rushes in.

During Exhale :-

• Diaphragm relaxes
• Volume of the thoracic cavity decreased
• Pressure in the lungs increased, and air rushes out.

Hence, When the diaphragm contracts - volume of chest cavity increased.

Answer 2

option A is correct........