BB 450 Unit 4 questions well answered
to pass
What does carbohydrate mean? - correct answer ✔✔carbon and water
What are the prefixes that tell us how many carbons? - correct answer ✔✔Mono-
=1
Di- = 2
Tri- = 3
Tetr- = 4
Pent- = 5
Hex- = 6
Hept- = 7
Oct- = 8
What is the general formula for carbohydrates? - correct answer ✔✔Cx(H2O)x
What are ketoses and aldoses? - correct answer ✔✔Ketoses = monosaccharide
containing one ketone group per molecule. (in it's acyclic form) = Ketones
Aldoses = An aldose is a monosaccharide with a carbon backbone chain with a
carbonyl group on the endmost carbon atom, making it an aldehyde, and hydroxyl
groups connected to all the other carbon atoms. = Aldehyde
,Aldoses are more easily oxidized than ketones
Ketones have their carbonyl group in position 2
Orientation of the hydroxides is the same for both
What is a Haworth projection and what is a Fischer projection? - correct answer
✔✔Hawthorn: represents the cyclic structure of monosaccharides with a simple
three-dimensional perspective. Ring structure
Fischer: a two-dimensional representation of a three-dimensional organic
molecule by projection. Linear model
What is an asymmetric carbon? - correct answer ✔✔An asymmetric carbon is a
carbon attached to four different atoms or groups of atoms.
Position of the hydroxyl is how you tell the L and D forms apart
L = hydroxyl on the left
D = hydroxyl on the right
What is an enantiomer? - correct answer ✔✔Mirror Images
Each of a pair of molecules that are mirror images of each other.
What do you know if you see a sugar molecule with multiple asymmetric centers?
- correct answer ✔✔You know that that molecule has many isomers
,Multiple asymmetric centers = many isomers
What is a diastereomer? - correct answer ✔✔stereoisomers that are not mirror
images of each other
Some carbons are the same and some are different in their configurations
What is an epimer? - correct answer ✔✔Diastereomers differing in configuration
of one carbon only the rest are the same
Do sugars stay in rings all the time? - correct answer ✔✔No, cyclization of sugars
takes them from linear to cyclic form.
Linearly the first carbon is only bound to three things, oxygen, hydrogen, and the
carbon chain. When the ring structure happens it's now bound differently.
There will be a new asymmetric carbon and we refer to that as the ~anomer
carbon~ it's always the carbonyl carbon
The hydroxyl can be in two different configurations.
It can then go back and forth between the two forms
, Which is the anomeric carbon? - correct answer ✔✔An anomeric carbon can be
identified as the carbonyl carbon (of the aldehyde or ketone functional group) in
the open-chain form of the sugar. It can also be identified as the carbon bonded to
the ring oxygen and a hydroxyl group in the cyclic form.
Anomers: Only differ in the configuration of the anomer carbon
What are the alpha and beta configs for the -OH on the anomeric carbon?
If you see alpha or beta in front of a molecule name, can you picture where the -
OH is? - correct answer ✔✔Alpha: The -OH group is pointed downwards
Beta: The -OH group is pointed upwards
What are the chair and boat conformations? Which is most favorable and why? -
correct answer ✔✔Chair: A six-membered ring conformation in which atoms 2, 3,
5, and 6 lie in the same plane, atom 1 lies above the plane, and atom 4 lies below
the plane.
Boat: A six-membered ring conformation in which atoms 1, 2, 4, and 5 are
coplanar, and atoms 3 and 6 are bent out of the plane in the same direction.
Chair is the more favorable form because there is less steric hindrance
What modifications can be added to sugars? - correct answer ✔✔Amine groups
can be put on the Carbon 2 of sugars
to pass
What does carbohydrate mean? - correct answer ✔✔carbon and water
What are the prefixes that tell us how many carbons? - correct answer ✔✔Mono-
=1
Di- = 2
Tri- = 3
Tetr- = 4
Pent- = 5
Hex- = 6
Hept- = 7
Oct- = 8
What is the general formula for carbohydrates? - correct answer ✔✔Cx(H2O)x
What are ketoses and aldoses? - correct answer ✔✔Ketoses = monosaccharide
containing one ketone group per molecule. (in it's acyclic form) = Ketones
Aldoses = An aldose is a monosaccharide with a carbon backbone chain with a
carbonyl group on the endmost carbon atom, making it an aldehyde, and hydroxyl
groups connected to all the other carbon atoms. = Aldehyde
,Aldoses are more easily oxidized than ketones
Ketones have their carbonyl group in position 2
Orientation of the hydroxides is the same for both
What is a Haworth projection and what is a Fischer projection? - correct answer
✔✔Hawthorn: represents the cyclic structure of monosaccharides with a simple
three-dimensional perspective. Ring structure
Fischer: a two-dimensional representation of a three-dimensional organic
molecule by projection. Linear model
What is an asymmetric carbon? - correct answer ✔✔An asymmetric carbon is a
carbon attached to four different atoms or groups of atoms.
Position of the hydroxyl is how you tell the L and D forms apart
L = hydroxyl on the left
D = hydroxyl on the right
What is an enantiomer? - correct answer ✔✔Mirror Images
Each of a pair of molecules that are mirror images of each other.
What do you know if you see a sugar molecule with multiple asymmetric centers?
- correct answer ✔✔You know that that molecule has many isomers
,Multiple asymmetric centers = many isomers
What is a diastereomer? - correct answer ✔✔stereoisomers that are not mirror
images of each other
Some carbons are the same and some are different in their configurations
What is an epimer? - correct answer ✔✔Diastereomers differing in configuration
of one carbon only the rest are the same
Do sugars stay in rings all the time? - correct answer ✔✔No, cyclization of sugars
takes them from linear to cyclic form.
Linearly the first carbon is only bound to three things, oxygen, hydrogen, and the
carbon chain. When the ring structure happens it's now bound differently.
There will be a new asymmetric carbon and we refer to that as the ~anomer
carbon~ it's always the carbonyl carbon
The hydroxyl can be in two different configurations.
It can then go back and forth between the two forms
, Which is the anomeric carbon? - correct answer ✔✔An anomeric carbon can be
identified as the carbonyl carbon (of the aldehyde or ketone functional group) in
the open-chain form of the sugar. It can also be identified as the carbon bonded to
the ring oxygen and a hydroxyl group in the cyclic form.
Anomers: Only differ in the configuration of the anomer carbon
What are the alpha and beta configs for the -OH on the anomeric carbon?
If you see alpha or beta in front of a molecule name, can you picture where the -
OH is? - correct answer ✔✔Alpha: The -OH group is pointed downwards
Beta: The -OH group is pointed upwards
What are the chair and boat conformations? Which is most favorable and why? -
correct answer ✔✔Chair: A six-membered ring conformation in which atoms 2, 3,
5, and 6 lie in the same plane, atom 1 lies above the plane, and atom 4 lies below
the plane.
Boat: A six-membered ring conformation in which atoms 1, 2, 4, and 5 are
coplanar, and atoms 3 and 6 are bent out of the plane in the same direction.
Chair is the more favorable form because there is less steric hindrance
What modifications can be added to sugars? - correct answer ✔✔Amine groups
can be put on the Carbon 2 of sugars
