Question

Arrange these statements in the right order to describe process of inhalation.
____ Air is drawn into the lungs
____ Air pressure in the chest cavity decreases
____ Lungs expand
____ The diaphragm contracts and flattens
____ The muscles between the ribs contract to move the ribs up and out

Answer 1

Answer:

1. The diaphragm contracts and flattens.
2. Air is drawn into the lungs
3. Lungs expand.
4. Air pressure in the chest cavity decreases.
5. The muscles between the ribs contract to move the ribs up and out.

Answer 2

Arrange these statements in the right order to describe process of inhalation.

____ The muscles between the ribs contract to move the ribs up and out

____ The diaphragm contracts and flattens

____ Air pressure in the chest cavity decreases

____ Lungs expand

-------Air is drawn into the lungs

Explanation:

Breathing

It is the exchange of gases taking in oxygen and giving out carbon dioxide.

Mechanism of breathing

Thoracic cavity

It is a cage like structure present in chest formed of :

RIBS,DIAPHRAGM,BACKBONE& ABDOMINAL MUSCLES.

During Inspiration

• Ribs: are pulled forward & upwards
• Diaphragm:becomes flat
• Ab.muscles: contract

Due to this, size of cavity increases thereby decreasing the pressure of air ,but outside pressure of air is high therefore air from outside moves to inside.

During Expiration  

Ribs: comes back to their original position

Diaphragm: again becomes dome shaped

Ab. Muscles :relax

Due to this size of cavity decreases thereby increasing the pressure of air but outside pressure of air is low therefore air from inside moves to outside.