Mechanical/ Physical Digestion

• During this process, food is broken down into smaller particles
• The smaller food particles have a larger surface area for digestive enzyme action to break the down further into simple molecules
• Chewing process (mastication)- food is broken down into smaller particles by the teeth and the tongue
• Bolus formation- the chewed food is mixed with saliva and rolled into a ball of food (bolus) using the tongue. The swallowing process starts with the tongue pushing the bolus through the pharynx, from where it enters the oesophagus
• Churning movements- these take place by contraction and relaxation of the muscles of the stomach wall. Food particles are broken down further for effective enzyme action and thoroughly mixed with gastric juice.
• Peristaltic movements- this is the rhythmic contraction and relaxation of the muscles in the wall of the alimentary canal. It helps move the food particles forward through the entire length of the alimentary canal