Look at the clip of the breathing in mammals.
Breathing in and out occurs due to changes taking place in the respiratory system structures of mammals. If any of this structures are damaged the mechanism of breathing in and out will not occur. Eventually, the organism will lack oxygen and suffocate.
From the clip you have watched:
1. Name the parts of the respiratory system of man.
2. Describe the change in volume and pressure of the lungs during breathing in and out process.