Physical Digestion (Cambridge (CIE) IGCSE Combined Science): Revision Note

Physical digestion (sometimes referred to as mechanical digestion) is the breakdown of food into smaller pieces without chemical change to the food molecules

It is mainly carried out by the chewing action of the teeth, the churning action of the stomach and the emulsification of fats by bile in the duodenum

The processes that take place during physical digestion help to increase the surface area of food

Increasing the surface area aids the action of enzymes during chemical digestion and speeds up the rate of digestion and absorption