Emphysema is a chronic lung disease that occurs when the air sacs in the lungs (called the alveoli) can no longer inflate and deflate to pump air in and out of the lungs as they should. Many ...

the ribs can move up and out to increase the volume of the thorax Balloons/lungs Can inflate and deflate, are elastic like the alveoli The balloons are large open spaces whereas the lungs are made ...