How the repertory system with following physiological requirements

For Example:
Place your hand on your ribs and inhale deeply. You’ll notice that your chest expands and your back straightens. As this occurs, air is rushing through your windpipe and branches off to either your left or right lung. After 20 to 30 more branch , branch points, oxygen in the air ends up in the alveoli where it diffuses into the liquid that only surrounds the alveoli, and slips into the blood. This microscopic gas exchange occurs rapidly, oxygen is taken into the body and carbon dioxide is totally removed from the body, and then you exhale. 
Hope that this helps you! =)