If food is directly introduced into the duodenum, which of the following would be most severely affected?

Mechanical digestion breaks large food particles down into smaller ones. As a result, food molecules become dissolved and thoroughly mixed with digestive enzymes. In the buccal cavity, teeth cut and grind food before it is swallowed and then smooth muscles of the stomach (and small intestine) churn the food. Mechanical digestion is severely affected if food is directly introduced into the duodenum.