Question

What causes air to enter and leave the lungs?

Answer 1

Just beneath the lungs, there is a sturdy sac-like muscle called the Diaphragm. It influences the pressure in our Lungs to a large extent. When the Diaphragm contracts, it decreases the pressure in our Lungs as compared to the outer environment. Thus, the air enters our body through the Nasal Cavity and makes its way to our Lungs. When the Diaphragm relaxes, it increases the pressure in our Lungs as compared to the outer environment. Thus, the air moves out of the Lungs and finally goes out of our body via the Nasal Cavity.