1. Breakdown of food happens mainly in the mouth + stomach, most of the absorption takes place in the duodenum and the small intestines
2. The has an extra layer of muscle (called oblique muscle), this enable it to mechanically breakdown churn the food with Hydrochloric acid
3.
MECHANICAL DIGESTION = M
CHEMICAL DIGESTION = C
- Teeth cut and crush food into smaller pieces (mastication or chewing), increasing surface area M
- Salivary amylase produced by the salivary glands breaks glucose into polysaccharides C
- The tongue moves to bolus (ball of food) to the pharynx (back of the mouth), the epiglottis moves to cover the trachea and the bolus is pushed down the oesophagus via peristalsis
- Churning occurs in the stomach as mentioned above to mix food with hydrochloric acid M
- Gastric enzymes produced in gastric pits in the stomach convert protein into polypeptides etc C
- The Chyme (after churning, the liquid produced is called Chyme) enters the duodenum via the pyloric sphincter
- Duodenum continues the breakdown of food into its monomers, mixing it with pancreatic enzymes C
- Emulsification takes place in the duodenum M, emulsification is not chemical digestion as the fats are being broken into smaller pieces and not yet being converted into lipids
- Chyle (liquid formed in the small intestine) to moved into the small intestine for absorption
- The small intestine also mixes the chyle with intestinal enzymes breaking it down further C
- It is absorbed via the villi, where capillary networks deliver nutrients to the rest of the body
- The remainder of the undigested food moves to the colon where is to broken down by the bacteria living there and water is absorbed
