Lesson 3 starch, glycogen and cellulose

Post on 22-Jan-2018

5,543 views 1 download

transcript

Starch, Glycogen and Cellulose

• To be able to relate the structure and function of the carbohydrates starch, glycogena dncellulose

Polysaccharides…

Glycogen

Starch Vs Glycogen…

Cellulose Hydrogen Bonding

Relating Structure to Function

1. Glucose – OH groups make it water soluble, easily coverted to pyruvate in glycolysis

2. Starch (amylose) – easily broken down into glucose, linear structure allows for close packing, hence good energy store

3. Glycogen – several branches of the carbohydrate can be cut off at once to supply energy quickly

4. Cellulose – hydroxyl groups form hydrogen bonds with neighbouring chains, holding the chains firmly together forming microfibrils with high tensile strength

Summary (P13-15)…Carbohydrate Type of

moleculeComponent monomers

Structure Function andlocation

Glucose Monomer α or ß glucose Linear or ring Aerobicrespiration, bloodstream

Test next lesson…

• Be able to draw both glucose isomers

• Be able to show a glycosidic bond

• Be able to show hydrolysis and condensationreactions

1) Choose colours for C, H , O

• Make 2 molecules of alpha glucose

• Join together by a glycosidic bond

• Join a 3rd alpha glucose to make AMYLOSE

Modelling carbohydrates…

• Select a colour for C, H, O

• Use grey plastic attachments to show bonds

1. Make a molecule of α and ß glucose

2. Make a molecule of maltose with a 1,4-glycosidic bond

3. Make a 1,4 glycosidic bond between 2 molecules of ß glucose

Draw each structure on paper next to your model

Specification Points