Polysaccharides Flashcards
What are polysaccharides?
Carbohydrates
What are polysaccharide molecules made from?
Large numbers of their monomers
How is a polysaccharide formed?
When two or more monosaccharides are joined together by condensation reactions
How are polysaccharides broken down into their constituent monosaccharides?
By a hydrolysis reaction
What are 3 polysaccharides?
Starch
Glycogen
Cellulose
Polysaccharide Starch - How do cells get energy?
Glucose
Polysaccharide Starch - What do plants store excess glucose as?
Starch
Polysaccharide Starch - When a plant needs more glucose for energy, what does it do?
Breaks down starch to release glucose
Polysaccharide Starch - How do plants get energy?
The cells get energy from glucose
The plants store the glucose as starch
When the plant needs more glucose for energy it breaks down the starch releasing the glucose
Polysaccharide Starch - What is starch a mixture of?
Two polysaccharides of alpha glucose: Amylose and Amylopectin
What is the structure of Amylopectin?
Long
Unbranched chain of a-glucose
Angles of glycosidic bonds give it a coiled structure
Hydrogen bonds hold its helical structure
Polysaccharide Starch - What is the function of Amylose?
Compact
Good for storage
Can fit more in a small space
Polysaccharide Starch - What is the structure of amylopectin?
Long
Branched chain of a-glucose
Side branches
Polysaccharide Starch - What is the function of amylopectin?
Side branches allow the enzymes to break down the molecule to get at the glycosidic bonds easily
Glucose can be released quickly
Polysaccharide Starch - What is starch in water?
Insoluble
Doesn’t affect water potential
Polysaccharide Starch - How is starch good for storage? (Water)
Doesn’t cause water to enter cells by osmosis which would make them swell
Polysaccharide Glycogen - How do animal cells get energy?
From glucose
Polysaccharide Glycogen - What do animals store excess glucose as?
Glycogen
Polysaccharide Glycogen - What is the structure of glycogen?
Long
Branched chain of a-glucose
Lots of side branches
Polysaccharide Glycogen - What is glycogen’s function?
Lots of side branches means stored Glucose can be released quickly
Compact so it is good for storage
Acts as an energy store
Polysaccharide Cellulose - What is the structure of cellulose?
Long
Unbranched chains of b-glucose
When b-glucose molecules bond they form straight cellulose chains
Chains linked together by hydrogen bonds to form microfibrils
Polysaccharide Cellulose - What is the function of cellulose?
Strong fibres (microfibrils) mean cellulose provides structural support for cells