nutrition

• 1: Hydrocloric acid
• 2: rennin
• 3: pepsinogen which is activated bu hydrocloric acids into pepsin

coagulates milk into curds (in infants)

• Neutralizes bacteria, 
• Activates pepsinogen (to convert into enzyme pepsin)
• Pepsin is secreted in the inactive form of pepsinogen to prevent it from damaging the cells that make it.

• Coagulates proteins into PEPTONS (or peptides)
• pepsinogen is secreted in a gastric glands in the stomach wall

• 1 - pancreatic juice
• 2 - bile

• 1: trypsin - 
• 2: lipase - 
• 3: amylase -

converts peptones into shorter chain polipeptides

converts fats into fatty acids and glycerol

converts polysaccharides into saccharides

action: emulsifies fats; neutralises the acid chyme from stomach

content: water, bile salts, bile pigments

• to include disaccharides digestion by:
• 1: maltase
• 2: sucrase
• 3: lactase
• 4: enterokinase
• 5: peptidases

converts polipeptides into amino acids

activates tripsin in pancreatic juice

to split disaccharides into monoaccharides

An enzyme is a substance consisting largely or wholly of PROTEIN that acts as a catalyst (a substance that speeds up the rate of chemical reaction without itself undergoing any permanent change).

building materials of the body  made up of interlinked polipeptide chains

a soluble protein formed in the early stage of protein breakdown during digestion.

• Polypeptides are groups of amino acids.
• Usually polypeptides are thousands of amino acids long. When polypeptides get long enough, they can fold over. The FIRST time they fold over on itself or to another polypeptide the sequence is then a protein.

• Amino acids are the building blocks of proteins. They are used a lot of body building as they are required for muscles to grow. 
•  An amino acid is smaller than a polypeptide. A polypeptide is usually smaller than a protein.

• energy giving nutrient syntesized by photosintesis in the plans.
• Made of carbon, hydrogen and oxygen
• C₆H₁₂O₆

• C₁₂H₂₂O₁₁
• Sucrose=1 glucose+1 fructose molecule
• Lactose=1glucose+1galactose
• Maltose=1glucose+1glucose
• two monoasaccharised chemically linked together

• Consists of many monosaccharides - formula (C₆H₁₀O₅)_n
• examples - starch - mainly in grains and veg foods,
• glycogen - form of animal starch storred in the liver and muscles
• cellulose - structural framework and fibrous parts of plants - steams, seeds, leaves and roots - not soluble, not providing the energy, acts as a roughage
• Pectin - in small quantities in many fruit and veg, no calorific value, gelly

• Fructose and galactose
• They have the same number of carbon and oxygen atoms (6) and 12 hydrogen atoms but they are arranged differently
• C₆H₁₂O₆

• a) three fatty acids+glycerole {has 3 hydroxyl(OH) groups which can combine with three fatty acid molecules}
• b)

• Acids found in lipids
• Differ in the amount of hydrogen they contain: 
• Saturated - all carbon atoms bond to hydrogen,
• Monounsaturated two carbon atoms have no hydrogen - therefore double bond in between them  - e.g in olive oil (oleic acid) , Polyunsaturated - more than one double bond in between carbon molecules 
• - linoleic acid (wheat germ oil) has 2 double bonds
• - linolenic acid in many veg oils has three double bonds
• polyunsaturated are essential fatty acids

• soft or oily in the room temp
• found mainly in veg foods and oils and fish