carbohydrates Flashcards
What is a monomer?
A small single molecule, which can join many other similar molecules to make up a polymer.
What is a polymer?
A large molecule made up of many smaller similar monomers joined together.
What are the 3 elements carbohydrates are made from?
Carbon, hydrogen and oxygen.
what are the single monomer units of carbohydrates?
Monosaccharides,
What is sucrose made with?
A-glucose and fructose
What is lactose made with?
B-glucose and galactose
What is maltose made with?
A-glucose and a-glucose
What is the bond joining monosaccharides together?
Glycosidic bond
What type of reactions joins and splits monosaccharides?
Join - condensation
splits - hydrolysis
What are the two types of starch?
Amylose and amylopectin
Features of amylose
-Long, unbranched chain of a-glucose.
- coiled structure and compact so good for storage.
-1-4 bonds.
Features of amylopectin
-Long, branched chain of a-glucose.
-1-4 and 1-6 bonds.
-Contains side branches which allow the enzymes that break down molecules get to the glycosidic bonds easily. This means glucose is released faster.
What features makes starch good for storage?
- Compact
- Insoluble in water, so doesn’t cause water to enter by osmosis.
Where’s starch found?
Found in plants (main energy sorage)
Features of glycogen
-Polysaccharide of alpha-glucose.
-Lots of side branches coming off it. This means stored glucose can be released quickly, which is important for energy release in mammals.
- Compact molecule so good for storage.
- Bonds are 1-4 and 1-6.
Where is glycogen found?
Found in animals (main energy storage)
Features of cellulose
- Cellulose is made of long, unbranched chains of beta-glucose.
-1-4 bond
What is cellulose chains linked by and what does this form?
- Linked together by hydrogen bonds to form strong fibres called microfibrils.
- Strong fibres mean cellulose provides structural support for cells.
Where is cellulose found?
Major component of cell walls in plants.
What is the test for carbohydrates?
Benedict’s test (reducing sugars test)
How does the structure of glycogen differ from amylopectin to make it a better energy store in animals?
- More compact
- More coiled
- Has more side branches, so glucose is released faster
Three properties of cellulose that make it suitable as the basis of plant cell walls.
1- flexible
2- high tensile strength
3- insoluble
Why do mammals store glycogen instead of glucose?
- Compact
- Metabolically inactive
Name the carbohydrate molecules used to store energy in plants and animals.
plants - starch
animals - glycogen
