2. Topic 15 Carbohydratesand Related Substances

3. A Balanced Diet Abalanced diet is the correct mixture and amount of the five food groups. They They are: Proteins Proteins e.g.Beans, meat & poultry Fats Fats e.g.Cheese milk & butter Carbohydrates: Carbohydrates: Pasta, rice and cakes. Vitamins:e.g. Vitamins:e.g. A,B,B12,C,E&D Minerals:e.g.Ca,Fe, Minerals:e.g.Ca,Fe, Zn & I etc.

4. Carbohydrates Carbohydrates are made up of three elements only i.e. Carbon, hydrogen and oxygen. Carbohydrates are made up of three elements only i.e. Carbon, hydrogen and oxygen. They have a General Formula of(C)x(H 2 O)y They have a General Formula of(C)x(H 2 O)y Carbohydrates provide our bodies with energy. Carbohydrates provide our bodies with energy.

5. 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)

6. 3. 3. Polysaccharides ( made up many monosaccharides joining together) eg Starch & 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 -

7. Breaking Carbohydrates Up Monosaccharides join by the removal of water molecules.i.e. Condensation Reaction. To break up Carbohydrates we ADD water.This is called Hydrolysis. Instead of water our bodies use Hydrochloric Acid Starch Glucose molecules

8. Digestion of Food For us to receive the benefit of food it must be absorbed into our For us to receive the benefit of food it must be absorbed into our bloodstream. Digestion happens in a number of stages: Digestion happens in a number of stages: First broken down in mouth by chewing and use of Enzymes in saliva. First broken down in mouth by chewing and use of Enzymes in saliva. Passes down gullet into stomach where Hydrolysis begins (stomach contains Hydrochloric Acid). Passes down gullet into stomach where Hydrolysis begins (stomach contains Hydrochloric Acid). Begins long journey through Small Intestine (22-26ft) and then into large intestine( 4-6ft ) where it finally absorbed into the blood. Begins long journey through Small Intestine (22-26ft) and then into large intestine( 4-6ft ) where it finally absorbed into the blood.

9. Digestion (continued) The large Intestine or Gut can be regarded a long tube which contains tiny pores. The large Intestine or Gut can be regarded a long tube which contains tiny pores. For the food to get through to the other side i.e. the bloodstream the food molecules must be broken up into small enough units. For the food to get through to the other side i.e. the bloodstream the food molecules must be broken up into small enough units. For example Starch must be broken into Glucose molecules. For example Starch must be broken into Glucose molecules.

10. Alkanols (Alcohols) The Alkanols are another Homologous series with General Formula C n H 2n+1 OH The Alkanols are another Homologous series with General Formula C n H 2n+1 OH Alkanols are generally used as solvents and cleaning agents. Alkanols are generally used as solvents and cleaning agents. Ethanol is the alkanol that is present in all alcoholic drinks. Ethanol is the alkanol that is present in all alcoholic drinks. It is made by a process called Fermentation in which sugar is turned into alcohol It 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 increase the alkanol concentration