Classification And Structure Flashcards
What are the functions of carbohydrates?
Energy storage, cell membrane structure
What are some simple (fast releasing) carbs?
Glucose, fructose, galactose, maltose, sucrose, and lactose
What are some complex (slow releasing) carbs?
Starch, glycogen, fiber
How are monosaccharides classified?
By the number of carbons and carbonyl groups
3 carbons = -triose
4 carbons = -tetrose
5 carbons = -pentose
6 carbons = -hexose
What is an example of a 3 carbon monosaccharide?
Glyceraldehyde
What is an example of 4 carbon monosaccharide?
Erythrose
What is an example of a 5 carbon monosaccharide?
Ribose
What is an example of a 6 carbon monosaccharide?
Glucose
What is the difference between an aldose and a ketose?
An aldose has an aldehyde group stuck at the end of the molecule
A ketose has a ketone group stuck in the middle of the molecule
What is an isomer?
molecules with the same chemical formula but different structures
What are epimers?
Molecules that differ in configuration around one carbon atom
What is an exmaple of an isomer?
Glucose and fructose
What is an example of an epimer?
Galactose and glucose
What are enantiomers?
Molecules that are mirror images of each other
What is a D-oriented enantiomer?
Molecules with functional groups that are oriented to the right
What is a L-oriented enantiomer?
Molecules with functional groups that are oriented to the left
Why are there such things as L-glucose and D-glucose?
Because different enzymes work on glucose that depends on the L and D configuration
Why are carbohydrates predominantly in a ring form?
Keto groups react with the hydroxyl groups on the same sugar and makes them more stable
Less than 1% are a straight chain
What is an anomeric carbon?
When the chain cyclizes the last and first carbon join together and create new pairs of isomers called alpha and beta
What are glycosidic bonds?
Bonds that link sugar molecules together
They are formed by glycosyltranferases
What determines if a sugar is in the alpha or beta configuration?
Alpha bond - the anomeric hydroxyl group is pointed downwards
Beta bond - the anomeric hydroxyl group is pointed upwards
What are some examples of disaccharides?
Maltose, sucrose, and lactose
What is maltose made of?
2 glucose molecules
What is sucrose made of?
A glucose and fructose molecule
