1.digestion is mixing food with Silva, which is when Mechanical digestion starts.
2.digestion is chewing food, which is a means of chemical digestion.
3.digestion is a reversible process due to mechanical digestion.
4.digestion is the process of breaking down food into smaller molecules
Explanation: digestion is the process of breaking down food by mechanical and enzymatic action in the alimentary canal into substances that can be used by the body.