Carbohydrates Flashcards
What is the formula for a carbohydrate?
Cn H2n On
Eg glucose C6H12O6
What are the purposes of carbohydrates in an organism?
Store of energy
Source of energy
Structural units
Why are carbohydrates good energy sources?
They are soluble in water and insoluble in non polar solvents
Draw the structure of alpha glucose
OH and OH. At bottom
Draw the structure of beta glucose
H and OH at he bottom
What is a condensation reaction?
A reaction where 2 molecules join together forming a bond by the removal of a water molecule.
What is a hydrolysis reaction?
Adding water into a bond in order to break it.
How are disaccharides formed?
Via a condensation reaction between two monosaccharides
Eg maltose = glucose + glucose
Reverse reaction would be hydrolysis
What are the common disaccharides?
Alpha glucose + alpha glucose = maltose
Alpha glucose + fructose = sucrose
Beta glucose + beta glucose = cellulose
Alpha glucose + galactose = lactose
What is starch
A polysaccharide made from alpha glucose ( amylopectin and amylose) which is found within plants.
Why is starch a good storage molecule?
Due to the 1-4 glycosidic bonding between the alpha glucose molecules, the starch molecule is coiled and compact and therefore can store a large amount of glucose in a short space. Starch is also insoluble and therefore is a great storage molecule in an organism.
What is the structure of glycogen?
Glycogen is a polysaccharide made from alpha glucose which has both 1-4 and 1-6 glycosidic bonding giving glycogen an extensive branched structure. This is a storage molecule found in animals.
Why is glycogen a good storage molecule?
Due to the extensive branching from the 1-6 glycosidic bonding, glycogen is a compact molecule and therefore can store a lot of glucose in a small space. It is easily hydrolysed from multiple branches releasing large amounts of glucose for energy quickly.
What is the structure of cellulose?
Cellulose is a polysaccharide made from long straight chains of beta glucose is 1-4 beta glycosidic bonding between each monomer. Every alternate beta glucose molecule is inverted enabling hydrogen bonds to from between the polysaccharide layers creating microfibrils.
How is cellulose adapted for its function?
The abundance of hydrogen bonds forming microfibrils gives cellulose a very high tensile strength. Also addition strength comes from the cross crossing of the hydrogen bonding between the polysaccharide layers.
Cellulose is tough and insoluble therefore being a great strength and support molecule.
Eg cell wall component.
