Presentation on theme: "A Balanced Diet nAnAnAnA balanced diet is the correct mixture and amount of the five food groups. nTnTnTnThey are: nPnPnPnProteins e.g.Beans, meat & poultry."— Presentation transcript:
A Balanced Diet nAnAnAnA balanced diet is the correct mixture and amount of the five food groups. nTnTnTnThey are: nPnPnPnProteins e.g.Beans, meat & poultry nFnFnFnFats e.g.Cheese milk & butter nCnCnCnCarbohydrates: Pasta, rice and cakes. nVnVnVnVitamins:e.g. A,B,B12,C,E&D nMnMnMnMinerals:e.g.Ca,Fe, Zn & I etc.
Carbohydrates n Carbohydrates are made up of three elements only i.e. Carbon, hydrogen and oxygen. n They have a General Formula of(C)x(H 2 O)y n Carbohydrates provide our bodies with energy.
There are 3 groups of Carbohydrate There are 3 groups of Carbohydrate n1n1. Monosaccharides (the simplest sugars) e.g. Glucose and Fructose, both have formula C 6 H 12 O 6 ie Isomers n2n2.Disaccharides e.g Sucrose & Maltose(made from two monosaccharides joining together)
n 3. n 3. Polysaccharides ( made up many monosaccharides joining together) egStarch & Cellulose.Approx 300 glucose units join together to make Starch. They join together by means of a CONDENSATION Reaction i.e.the removal of water molecules between monosaccharides. The Formula of starch is -(C 6 H 10 O 5 ) n -
Tests for Carbohydrates nnTnnTest for Glucose: Add Benedicts solution and heat in a water – bath. If glucose is present the solution will turn from blue to orange (brick-red). This also works for Fructose(which is an Isomer of glucose) There is no practicaltest for sucrose Test for Starch:Add Iodine solution. If Starch is present it will turn Blue/Black.
Breaking Carbohydrates Up nMnMnMnMonosaccharides join by the removal of water molecules.i.e.a Condensation Reaction. nnTnnTo break up Carbohydrates we ADD water.This is called Hydrolysis. nnInnInstead of water our bodies use Hydrochloric Acid Starch Glucose molecules
Digestion of Food n For us to receive the benefit of food it must be absorbed into our n For us to receive the benefit of food it must be absorbed into our bloodstream. n Digestion happens in a number of stages: n First broken down in mouth by chewing and use of Enzymes in saliva. n Passes down gullet into stomach where Hydrolysis begins (stomach contains Hydrochloric Acid). n Begins long journey through Small Intestine (22-26ft) and then into large intestine( 4-6ft ) where it finally absorbed into the blood.
Digestion(contd). nTnTnTnThe large Intestine or Gut can be regarded a long tube which contains tiny pores. nFnFnFnFor the food to get through to the other side i.e. the bloodstream the food molecules must be broken up into small enough units. nFnFnFnFor example Starch must be broken into Glucose molecules.
Alkanols (Alcohols) nTnTnTnThe Alkanols are another Homologous series with General Formula CnH2n+1OH nAnAnAnAlkanols are generally used as solvents and cleaning agents. nEnEnEnEthanol is the alkanol that is present in all alcoholic drinks. nInInInIt is made by a process called Fermentation in which sugar is turned into alcohol C 6 H 12 O 6 C 2 H 5 OH + CO 2 yeast Yeast acts as a Catalyst since it contains Enzymes (a Biological Catalyst) which will only work at a specific pH and Temperature The mixture is finally Distilled to purify it