How do we sneeze?

A sneeze is a masterpiece of coordination:

1. The chest muscles and diaphragm force a rapid intake of air.
2. The windpipe closes, trapping the air in the lungs.
3. The stomach muscles force the air upwards, while the chest muscles increase the air pressure in the lungs.
4. The windpipe snaps open and the pressurised air explodes out.
5. Muscles at the back of the nasal channels contract, channelling most of the air out through the nostrils.