Carbohydrate Chemistry - MCAT Practice Questions
The convention used to designate the configurations of chiral carbons, based
on the forms of glyceraldehyde, is the:
D and L system
Nearly all carbohydrates found in nature are in which configuration?
D-configuration
The general chemical formula for carbohydrates is usually
Cm(H2O)n, leading to the common name:
Hydrates of carbon
A chiral molecule is defined as one that:
Lacks an internal plane of symmetry and has a non-superimposable mirror
image
Which type of stereoisomers are non-superimposable and are mirror images of
each other?
Enantiomers
Which type of stereoisomers are non-superimposable and are NOT mirror images
of each other?
Diastereomers
Epimers are a subtype of diastereomers that differ at exactly how many
chiral carbons?
One
Anomers are a subtype of epimers that specifically differ at the:
Anomeric carbon
What process is described as the formation of rings from straight-chain
carbohydrates?
Cyclization
A carbon that is not a stereocenter in the acyclic form, but becomes one in
the cyclic form, is called a(n):
Anomeric carbon
A cyclic carbohydrate structure where the group on the anomeric carbon is
pointing down is designated as a(n):
α-anomer
A cyclic carbohydrate structure where the group on the anomeric carbon is
pointing up is designated as a(n):
β-anomer
The spontaneous shift from one anomeric form (α or β) to another, often via
the straight-chain intermediate, is called:
Mutarotation
Haworth projections are structural formulas used to represent the cyclic
structure of:
Monosaccharides
What are single carbohydrate units called?
Monosaccharides
To be classified as a reducing sugar, the carbohydrate must have a(n):
-OH group attached to the anomeric carbon
What type of sugar is formed when a hydroxyl group is replaced with a
hydrogen atom?
Deoxy sugar
The reaction where a sugar reacts with a carboxylic acid or its derivative
to form an ester is known as:
Sugar esterification
The basis for building complex carbohydrates, which requires the anomeric
carbon to link to another sugar, is:
Glycoside formation
What forms as a result of a glycosidic bond between two monosaccharide
subunits?
Disaccharide