Polysaccharides Flashcards
How is a polysaccharide formed?
When more than two monosaccharides are joined together by condensation reactions.
How can polysaccharides be broken down into their monosaccharides?
Hydrolysis reactions.
Examples of polysaccharides?
Starch.
Glycogen.
Cellulose.
Where do cells get energy from?
Glucose.
How do plants store excess glucose?
Starch. When a plant needs more glucose for energy it breaks down starch to release glucose.
Which two polysaccharides is starch a mixture of?
Two polysaccharides of alpha-glucose.
Amylose.
Amylopectin.
Starch
What is amylose?
A long, unbranched chain of alpha-glucose.
Starch
What is the structure of amylose?
The angles of the glycosidic bonds give it a coiled structure.
Starch
Why is the structure of amylose beneficial?
It is compact, which makes it good for storage as you can fit more into a small space.
Starch
What is amylopectin?
A long, branched chain of alpha-glucose.
Starch
What does the side branches of amylopectin allow?
The enzymes that break down the molecule to get at the glycosidic bonds more easily, which means that glucose can be released quickly.
Starch
How is starch good for storage?
It is insoluble in water and doesn’t affect water potential, so it doesn’t cause water to enter cells by osmosis, which would make them swell.
How do animals store excess glucose?
Glycogen.
What is the structure of glycogen?
It is very similar to the structure of amylopectin, except it has many more side branches coming off it.
How are the side branches of glycogen beneficial?
Glucose can be release quickly, which is important for energy release in animals. It is also very compact, so is good for storage.
