6.3.4 Mechanical and physical digestion (Unfinished)

Mechanical and physical digestion

Core

• Define digestion

• Describe the role of longitudinal and circular 

muscles in peristalsis

• Outline the role of bile in emulsifying fats, 

to increase the surface area for the action of 

enzymes

Digestion is the breaking down of food molecules into smaller food molecules in the Alimentary Canal. These molecules are broken down from large insoluble molecules into smaller water - soluble molecules using chemical and mechanical processes.