Question 1

Which is not a glycoconjugate?

Accepted Answer

A)  proteoglycan 
B)  glycolipid 
C)  glycoprotein 
D)  homoglycan 
A)  proteoglycan 
B)  glycolipid 
C)  glycoprotein 
D)  homoglycan D

Question 2

a-amylases hydrolyze (a-1→4) linkages and β-amylases hydrolyze (β-1→4) linkages, but neither attack (a-1→6) linkages.

Accepted Answer

A) True 
 B)False  False

Question 3

Heteroglycan chains may or may not be covalently bound to proteins in proteoglycans.

Accepted Answer

A) True 
 B)False  True

Question 4

Enzymatic lengthening and degradation of glycogen occurs only at the non-reducing ends.

Accepted Answer

A) True 
 B)False

Question 5

The main difference between structures of amylopectin and glycogen is the specific sugar subunit.

Accepted Answer

A) True 
 B)False

Question 6

An oligosaccharide nodulation factor from one species can stimulate symbiosis in another species.

Accepted Answer

A) True 
 B)False

Question 7

You have two bottles, each of which contains a white, crystalline substance. Your lab director tells you that one contains lactose and the other sucrose. Your job is to determine which bottle contains which sugar. Which procedure would you use?

Accepted Answer

A)  Test both for solubility in water. Sucrose is very soluble; lactose is only minimally soluble. 
B)  Test for the ability to reduce Ag+. Only lactose will react. 
C)  Dissolve each in water and record the pH. Lactose is far more acidic than sucrose. 
D)  React each with bromine Br2) water. Only sucrose will react. 
A)  Test both for solubility in water. Sucrose is very soluble; lactose is only minimally soluble. 
B)  Test for the ability to reduce Ag+. Only lactose will react. 
C)  Dissolve each in water and record the pH. Lactose is far more acidic than sucrose. 
D)  React each with bromine Br2) water. Only sucrose will react.

Question 8

The intramolecular cyclization reaction of glucose in solution .

Accepted Answer

A)  generates a chiral center 
B)  yields a hemiacetal 
C)  usually forms a pyranose 
D)  All of the above 
A)  generates a chiral center 
B)  yields a hemiacetal 
C)  usually forms a pyranose 
D)  All of the above

Question 9

contain NeuNAc residues and sulfated sugars, and their negative charges contribute to the viscosity of mucins.

Accepted Answer

A)  Proteoglycans 
B)  N-linked polysaccharides 
C)  O-linked polysaccharides 
D)  Hyaluronic acid 
E)  All of the above 
A)  Proteoglycans 
B)  N-linked polysaccharides 
C)  O-linked polysaccharides 
D)  Hyaluronic acid 
E)  All of the above

Question 10

Pyranose rings are usually most stable when the ring adopts a conformation with the bulkiest ring substituents in positions.

Accepted Answer

A)  chair; equatorial 
B)  chair; axial 
C)  boat; equatorial 
D)  boat; axial 
A)  chair; equatorial 
B)  chair; axial 
C)  boat; equatorial 
D)  boat; axial

Question 11

Enzymes that hydrolyze cellulose cannot hydrolyze amylopectin.

Accepted Answer

A) True 
 B)False

Question 12

DNA could be referred to as a glycoside.

Accepted Answer

A) True 
 B)False

Question 13

The structure of a disaccharide is shown below. Which statement applies?

Accepted Answer

A)  Both rings A and B are in equilibrium with an open chain form. 
B)  Only ring A is in equilibrium with an open chain form. 
C)  Only ring B is in equilibrium with an open chain form. 
D)  Neither ring is in equilibrium with an open chain form. 
A)  Both rings A and B are in equilibrium with an open chain form. 
B)  Only ring A is in equilibrium with an open chain form. 
C)  Only ring B is in equilibrium with an open chain form. 
D)  Neither ring is in equilibrium with an open chain form.

Question 14

Amylase is a hydrolase that is an .

Accepted Answer

A)  endonuclease 
B)  endoglycosidase 
C)  exonuclease 
D)  exoglycosidase that removes maltose 
E)  exoglycosidase that removes glucose monomers 
A)  endonuclease 
B)  endoglycosidase 
C)  exonuclease 
D)  exoglycosidase that removes maltose 
E)  exoglycosidase that removes glucose monomers

Question 15

The bacterial cell wall is sensitive to penicillin because it

Accepted Answer

A)  blocks the linkage of the MurNAc and GlcNAc subunits. 
B)  blocks the pentaglycine bridge cross linkage. 
C)  binds to an enzyme which recognizes D-alanine-D-alanine dipeptide. 
D)  is not attacked by enzymes in animal cells. 
E)  All of the above 
A)  blocks the linkage of the MurNAc and GlcNAc subunits. 
B)  blocks the pentaglycine bridge cross linkage. 
C)  binds to an enzyme which recognizes D-alanine-D-alanine dipeptide. 
D)  is not attacked by enzymes in animal cells. 
E)  All of the above

Question 16

Below is the structure for a cyclic D-monosaccharide. Which is the anomeric carbon atom?

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
E)  5 
A)  1 
B)  2 
C)  3 
D)  4 
E)  5

Question 17

Monosaccharide derivatives in which an amino group replaces one of the hydroxyl groups may have important roles in

Accepted Answer

A)  DNA structure. 
B)  intermediary metabolisms. 
C)  vitamin C. 
D)  sialic acids. 
E)  All of the above 
A)  DNA structure. 
B)  intermediary metabolisms. 
C)  vitamin C. 
D)  sialic acids. 
E)  All of the above

Question 18

Which statement is false about the sugar units in DNA?

Accepted Answer

A)  They are cyclic in DNA. 
B)  It is a deoxy form of ribose 
C)  It is an epimer of glucose. 
D)  It has a D-configuration 
A)  They are cyclic in DNA. 
B)  It is a deoxy form of ribose 
C)  It is an epimer of glucose. 
D)  It has a D-configuration

Question 19

The Fischer projections of linear D-glucose and D-galactose are shown below. These two molecules are .

Accepted Answer

A)  epimers 
B)  enantiomers 
C)  anomers 
D)  structural constitutional) isomers 
A)  epimers 
B)  enantiomers 
C)  anomers 
D)  structural constitutional) isomers

Question 20

In solution only one anomeric form of a monosaccharide will be present.

Accepted Answer

A) True 
 B)False

Exam 8: Carbohydrates

Which is not a glycoconjugate?

a-amylases hydrolyze (a-1→4) linkages and β-amylases hydrolyze (β-1→4) linkages, but neither attack (a-1→6) linkages.

Heteroglycan chains may or may not be covalently bound to proteins in proteoglycans.

Enzymatic lengthening and degradation of glycogen occurs only at the non-reducing ends.

The main difference between structures of amylopectin and glycogen is the specific sugar subunit.

An oligosaccharide nodulation factor from one species can stimulate symbiosis in another species.

You have two bottles, each of which contains a white, crystalline substance. Your lab director tells you that one contains lactose and the other sucrose. Your job is to determine which bottle contains which sugar. Which procedure would you use?

The intramolecular cyclization reaction of glucose in solution .

contain NeuNAc residues and sulfated sugars, and their negative charges contribute to the viscosity of mucins.

Pyranose rings are usually most stable when the ring adopts a conformation with the bulkiest ring substituents in positions.

Enzymes that hydrolyze cellulose cannot hydrolyze amylopectin.

DNA could be referred to as a glycoside.

The structure of a disaccharide is shown below. Which statement applies?

Amylase is a hydrolase that is an .

The bacterial cell wall is sensitive to penicillin because it

Below is the structure for a cyclic D-monosaccharide. Which is the anomeric carbon atom?

Monosaccharide derivatives in which an amino group replaces one of the hydroxyl groups may have important roles in

Which statement is false about the sugar units in DNA?

The Fischer projections of linear D-glucose and D-galactose are shown below. These two molecules are .

In solution only one anomeric form of a monosaccharide will be present.

Introduction to Biochemistry

Water

Amino Acids and the Primary Structures of Proteins

Proteins: Three-Dimensional Structure and Function

Properties of Enzymes

Mechanisms of Enzymes

Coenzymes and Vitamins

Lipids and Membranes

Introduction to Metabolism

Glycolysis

Gluconeogenesis, the Pentose Phosphate Pathway, and Glycogen Metabolism

The Citric Acid Cycle

Electron Transport and Oxidative Phosphorylation

Photosynthesis

Lipid Metabolism

Amino Acid Metabolism

Nucleotide Metabolism

Nucleic Acids

Dna Replication, Repair, and Recombination

Transcription and Rna Processing

Protein Synthesis

Recombinant Dna Technology

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