1. What the body does with the food we eat!
Nutrition
What the body does with the
food we eat!

2. Processing of nutrients
Ingestion
Digestion
Absorption
Assimilation
Egestion

3. Ingestion Taking food into the alimentary canal
Starts with putting food in your mouth
Pulping with teeth
Mixing with saliva
Swallowing

4. Upper gastrointestinal tract
Mouth
Teeth
Tongue
Pharynx
Oesophogus
Accessory glands
Slaivary glands (submandibular, sublingual, parotid
Located around oral cavity
Produces amylase to act on polysaccharides

5. Digestion
The process of digestion is triggered by the sight, smell or taste of food.
The stomach is a storage bin:-
is a food mixer, the strong muscles contract and mash the food into a sticky, slushy mass
Is a sterilizing system, where the cells in the stomach produce an acid which kills germs in "bad" food
is a digestive tub, the stomach produces digestive fluid which splits and cracks the chemicals in food

6. Types of digestion
Mechanical – Food is physically broken down by teeth and segmentation (small intestines) peristalsis (large intestines)
Chemically – Food molecules are broken down by enzymes
Bacteria – ferment any remaining carbohydrates and convert proteins into amino acids. Decompose watse.

7. Chemical digestion Carbo-hydrates Amylases Fats Lipases Tri-glycerides
Starches and polysaccharides into disaccharides
Mono-saccharides
Fats
Lipases
Tri-glycerides
Fatty acids and glycerol
Proteins
Proteases
Peptones and polypeptides
Amino acids

8. Lower accessory organs
Gastric glands – produce pepsin and HCI
Pancreas – produces enzymes
Intestinal glands – produces enzymes to act in small intestine

9. The liver Produces bile Deactivates amino acids
Stores various fats and water soluble vits
Synthesises vit A
Detoxifies drugs
Metabolises alcohol
Desaturates fats
Produces heat
Breaks down worn out blood cells

10. The Gall Bladder Stores and concentrates bile.
Its function is to emulsify fats and neutralise stomach acids

11. Absorption Mostly happens in the small intestine
Ileum – water soluble nutrients, vitamins & minerals
Lipids – into lymph
Colon – re-absorbs water

12. Assimilation Happens at cell level Carbohydrates – energy
Proteins – structure & repair
Fat – insulation, protection & vitamins

13. Egestion Is expulsion from the alimentary canal
Undigested food remains are expelled
It occurs through the anus