Bio-Unit 1.1:Polysaccharides

Feature

Starch

Glycogen

Cellulose

Glucose monomer

alpha

alpha

beta

Shape of molecules

-glycosidic bonds from condensation reactions-unbranched chains-tight coils

-glycosidic bonds from condensation reactions-branched

-glycosidic bonds from condensation reactions

Found in animals or plants

plants

animals

plants (cell wall)

Function

energy storage

energy storage

structural

Adaptations to function

-insoluble: no effect of osmosis-compact: can fit a lot into a small space-large and insoluble: doesn’t diffuse out of cell

-insoluble: no effect of osmosis-compact: can fit a lot into a small space-branched: many ends for enzymes to start hydrolysis reactions-large and insoluble: doesn’t diffuse out of cell

- strong: unbranched chains linked together by H bonds + microfibrils join together to form fibres i

Food test

iodine solution+: orange>blue/black