Polysaccharides Flashcards
What is a polysaccharide?
a carbohydrate
How are polysaccharides broken down?
Hydrolysis
What is a polysaccharide made up of?
More than 2 monosaccharides
How are polysaccharides formed?
Condensation reaction
What are the three main polysaccharides?
Starch
Glycogen
Cellulose
What do plants store excess glucose as?
Starch
What two polysaccharides make up starch?
Amylose
Amylopectin
What is the structure of amylose?
Long, unbranched chains
Coiled structure
What type of bonds are there in amylose and how do these help?
Hydrogen
They hold its helical structure together
What is amylose good for and why?
Storage
It is compact so you can fit more into a small space
What type of glucose makes up amylose?
alpha
What is the structure of amylopectin?
Long, branched chains
How does the structure of amylopectin benefit it for releasing glucose quickly?
The side branches allow the enzymes to get at the glycosidic bonds easily
Is starch soluble or insoluble in water?
insoluble
What do animals store excess glucose as?
Glycogen
Which polysaccharide is glycogen similar to in its structure?
amylopectin
Which type of glucose does glycogen contain?
alpha
How is glycogen a good storage molecule?
It is compact
What is the structure of cellulose?
Long, unbranched chains
What type of glucose is cellulose made up of?
Beta
What bonds link cellulose chains together?
Hydrogen bonds
What is formed when cellulose chains link together?
Strong fibres called microfibrils
What does cellulose provide?
structural support
What is the function of glycogen?
Energy store
What is used to test for starch?
Iodine
Describe the test for starch.
1) Add iodine which has been dissolved in potassium iodide solution to the test sample
2)Positive =Blue/black
Negative= brown/orange
