Lesson 3 starch, glycogen and cellulose

Structure and function of carbohydrates

1. Starch, Glycogen and Cellulose To be able to relate the structure and function of the carbohydrates starch, glycogena dn cellulose

2. Polysaccharides…

3. Glycogen

4. Starch Vs Glycogen…

5. Cellulose Hydrogen Bonding

6. Relating Structure to Function Glucose – OH groups make it water soluble, easily coverted to pyruvate in glycolysis Starch ( amylose ) – easily broken down into glucose, linear structure allows for close packing, hence good energy store Glycogen – several branches of the carbohydrate can be cut off at once to supply energy quickly Cellulose – hydroxyl groups form hydrogen bonds with neighbouring chains, holding the chains firmly together forming microfibrils with high tensile strength

7. Summary ( P13-15 )… Carbohydrate Type of molecule Component monomers Structure Function and location Glucose Monomer α or ß glucose Linear or ring Aerobic respiration, bloodstream

8. Test next lesson… Be able to draw both glucose isomers Be able to show a glycosidic bond Be able to show hydrolysis and condensation reactions

9. 1) Choose colours for C, H , O Make 2 molecules of alpha glucose Join together by a glycosidic bond Join a 3 rd alpha glucose to make AMYLOSE

10. Modelling carbohydrates… Select a colour for C, H, O Use grey plastic attachments to show bonds Make a molecule of α and ß glucose Make a molecule of maltose with a 1,4-glycosidic bond Make a 1,4 glycosidic bond between 2 molecules of ß glucose Draw each structure on paper next to your model

11. Specification Points