Lecture 11: Carbohydrates I

Question 0

Aldose-ketose pairs are examples of which type of isomers?

Answer 0

Constitutional isomers

Question 1

Name two different aldose-ketose pairs.

Answer 1

Glucose & Fructose

Glyceraldehyde & Dihydroxyacetone

Question 2

What are constitutional isomers?

Answer 2

Molecules that differ in the order of attachment of atoms

Question 3

Give an example of enantiomers.

Answer 3

D-glyceraldehyde & L-glyceraldehyde

Question 4

Give 2 examples of diastereoisomers

Answer 4

D-glucose & D-mannose (epimers)

alpha-D-glucose & beta-D-glucose (anomers)

Question 5

What are stereoisomers?

Answer 5

Molecules that have the same order, but the spatial arrangement is different.
Enantiomers & Diastereoisomers

Question 6

What are enantiomers?

Answer 6

Nonsuperimposable mirror image molecules

Question 7

What are diastereoisomers?

Answer 7

Isomers that are not mirror images

Question 8

What is the Fehling’s reagent?

Answer 8

It is used to test if reducing sugar is in the urine…b/c you have more than normal amount in blood stream

Question 9

What is Pyran?

Answer 9

A 6 atom ring with 5 C’s and an Oxygen

Question 10

What is Furan?

Answer 10

A 5 member ring with 4 C’s and an Oxygen

Question 11

What is a glycosidic bond?

Answer 11

When an anomeric C participates in bonding with a C of another sugar

Question 12

What is the Maltose bond?

Answer 12

Alpha-1,4 bond between two glucose molecules

Question 13

What is maltase?

Answer 13

The enzyme that breaks down maltose

Question 14

What is the sucrose bond?

Answer 14

Alpha-1, Beta-2 bond between glucose & fructose

It’s a non-reducing sugar

Question 15

What is the lactose bond?

Answer 15

Beta-1,4 galactose & glucose

Question 16

What makes a sugar a reducing sugar?

Answer 16

It has a free anomeric C

Question 17

What is lactase?

Answer 17

The enzyme that breaks down lactose

Question 18

What is sucrase?

Answer 18

The enzyme that breaks down sucrose

Question 19

What C position causes the difference between glucose/mannose?

Answer 19

The second C position is flipped (from anomeric C)

Question 20

What C position causes the difference between glucose/galactose?

Answer 20

The fourth C position is flipped (from anomeric C)

Question 21

T/F: Dihydroxyacetone and Glyceraldehyde are isomers.

Answer 21

True

Question 22

T/F: Glucose relates to Fructose as an aldose-ketose pair.

Answer 22

True

Question 23

What is an epimer?

Answer 23

An isomer that differs at one of several asymmetric C’s

Question 24

What is an anomer?

Answer 24

Molecules that differ at new asymmetric C upon ring closer

Question 25

What is Glycation?

Answer 25

Covalent bonding of protein or lipid with broken down sugar (3DG or MG), such as fructose or glucose, without controlling action of enzyme…