Fill the blank spaces to complete the text.
Inspiration
1. The intercostal muscles while the intercostal muscles relax
2. The ribs are pulled and , increasing the volume in the
3. The diaphragm muscles contract causing it to , increasing the volume in the thorax
4. The increased thorax volume leads to a reduction of in the lungs
5. The pressure is greater than the pressure so air is forced into the lungs