Answer :

diaphragm:
it is a sheet of muscle which is doomed shape....in thoracic cavity...
role in digestion:
it can increase intra abdominal pressure and help to expel
1 vomit
2 urine
3 feces...

diaphragam is a sheet of muscle situated below the lungs and it helps in regular breathing.the sheet contracts and expands when we breathe in and out