10.3 Starch, Glycogen And Cellulose Flashcards
In the plant, in what form is starch found?
As starch gains.
Starch is a mono/di/polysaccharide?
Polysaccharide.
Where do large amounts of starch occur?
Seeds and storage organs, such a potato tubers.
What is the major energy source in most diets?
Starch
What is starch made up of and what are they linked by?
Chains of alpha glucose monosaccharides linked by glycosidic bonds.
How are glycosidic bonds formed?
By condensation reactions.
What is the main role of starch?
Energy storage.
Why is starch suited to energy storage?
- it is insoluble and doesn’t draw water into the cells by osmosis
- being insoluble, it does not easily diffuse out of cells
- it is compact, so a lot of it can be stored in a small space
- when hydrolysed it forms alpha-glucose, which is both easily transported and readily used in respiration.
Starch is NEVER found in…
Animal cells.
Glycogen has a similar structure to …
Starch ( but has shorter chains and is more highly branched).
Glycogen is sometimes called ‘animal starch’ because…
It is the major carbohydrate storage product of animals.
How is glycogen stored?
In animals it is stored as small granules mainly in the muscles and liver.
Glycogens structure suits it’s functions for the same…
Reasons as starch but it is even more readily hydrolysed to alpha glucose because it is made up of smaller chains.
Glycogen is NEVER…
Found in plant cells.
How does cellulose differ from starch and glycogen?
It is made of monomers of beta glucose rather than alpha glucose.