Question 1

Why is methyl iodide used in the classical method of exhaustive methylation to determine the positions of glycosidic bonds in a linear polysaccharide?

Accepted Answer

A)  All free hydroxyls become unstable, allowing hydrolysis of only glycosidic bonds to occur in acid. 
B)  All free hydroxyls become stable, allowing hydrolysis of only glycosidic bonds to occur in acid. 
C)  All glycosidic bonds react with methyl iodide. 
D)  All glycosidic bonds become stable for treatment with acid. 
E)  All glycosidic bonds are hydrolyzed with methyl iodide. 
A)  All free hydroxyls become unstable, allowing hydrolysis of only glycosidic bonds to occur in acid. 
B)  All free hydroxyls become stable, allowing hydrolysis of only glycosidic bonds to occur in acid. 
C)  All glycosidic bonds react with methyl iodide. 
D)  All glycosidic bonds become stable for treatment with acid. 
E)  All glycosidic bonds are hydrolyzed with methyl iodide.

Question 2

Define each in 20 words or fewer:
(a) anomeric carbon
(b) enantiomers
(c) furanose
(d) pyranose
(e) glycoside
(f) epimers
(g) aldose
(h) ketose

Accepted Answer

(a) Anomeric carbon: The carbon in a car

Question 3

Explain why all mono- and disaccharides are soluble in water.

Accepted Answer

Mono- and disaccharides are soluble in w

Question 4

Which factor is NOT a part of determining the complete structure of an oligosaccharide or polysaccharide?

Accepted Answer

A)  determination of linear sequence 
B)  determination of lectin partners 
C)  determination of branching positions 
D)  determination of glycosidic linkages 
E)  determination of monosaccharide configuration 
A)  determination of linear sequence 
B)  determination of lectin partners 
C)  determination of branching positions 
D)  determination of glycosidic linkages 
E)  determination of monosaccharide configuration

Question 5

Which sequence is the CORRECT one for leukocyte extravasion in the inflammatory response?

Accepted Answer

A)  integrin binding $\rightarrow$ selectin binding $\rightarrow$adhesion $\rightarrow$ arrest $\rightarrow$ extravasion 
B)  adhesion $\rightarrow$ integrin binding $\rightarrow$ selectin binding$\rightarrow$ arrest $\rightarrow$extravasion 
C)  selectin binding $\rightarrow$integrin binding $\rightarrow$ adhesion $\rightarrow$ arrest $\rightarrow$ extravasion 
D)  integrin binding $\rightarrow$ adhesion $\rightarrow$selectin binding $\rightarrow$ arrest $\rightarrow$ extravasion 
E)  selectin binding $\rightarrow$ adhesion $\rightarrow$ integrin binding $\rightarrow$arrest $\rightarrow$extravasion 
A)  integrin binding $\rightarrow$ selectin binding $\rightarrow$adhesion $\rightarrow$ arrest $\rightarrow$ extravasion 
B)  adhesion $\rightarrow$ integrin binding $\rightarrow$ selectin binding$\rightarrow$ arrest $\rightarrow$extravasion 
C)  selectin binding $\rightarrow$integrin binding $\rightarrow$ adhesion $\rightarrow$ arrest $\rightarrow$ extravasion 
D)  integrin binding $\rightarrow$ adhesion $\rightarrow$selectin binding $\rightarrow$ arrest $\rightarrow$ extravasion 
E)  selectin binding $\rightarrow$ adhesion $\rightarrow$ integrin binding $\rightarrow$arrest $\rightarrow$extravasion

Question 6

It is useful to analyze hemoglobin glycation to determine a(n):

Accepted Answer

A)  single-time measurement of blood glucose levels. 
B)  single-time measurement of blood glycogen levels. 
C)  average blood glucose level over days or weeks. 
D)  average blood glycogen level over days or weeks. 
E)  None of the answers is correct. 
A)  single-time measurement of blood glucose levels. 
B)  single-time measurement of blood glycogen levels. 
C)  average blood glucose level over days or weeks. 
D)  average blood glycogen level over days or weeks. 
E)  None of the answers is correct.

Question 7

Which statement is FALSE about the enzyme lysozyme?

Accepted Answer

A)  It is the active ingredient in penicillin. 
B)  It is found in human tears. 
C)  It is produced by some bacterial viruses. 
D)  It hydrolyzes the ($\beta$1$\rightarrow$ 4) glycosidic bond of peptidoglycan. 
E)  It causes osmotic lysis of bacterial cells. 
A)  It is the active ingredient in penicillin. 
B)  It is found in human tears. 
C)  It is produced by some bacterial viruses. 
D)  It hydrolyzes the ($\beta$1$\rightarrow$ 4) glycosidic bond of peptidoglycan. 
E)  It causes osmotic lysis of bacterial cells.

Question 8

When two carbohydrates are epimers:

Accepted Answer

A)  one is a pyranose, the other a furanose. 
B)  one is an aldose, the other a ketose. 
C)  they differ in length by one carbon. 
D)  they differ only in the configuration around one carbon atom. 
E)  they rotate plane-polarized light in the same direction. 
A)  one is a pyranose, the other a furanose. 
B)  one is an aldose, the other a ketose. 
C)  they differ in length by one carbon. 
D)  they differ only in the configuration around one carbon atom. 
E)  they rotate plane-polarized light in the same direction.

Question 9

Which statement about dextrans is FALSE?

Accepted Answer

A)  Dextrans are bacterial and yeast polysaccharides. 
B)  All dextrans are made up of ($\alpha$1$\rightarrow$ 4)-linked poly-D-glucose. 
C)  All dextrans have ($\alpha$1$\rightarrow$ 3) branches. 
D)  Some dextrans have ($\alpha$1$\rightarrow$ 2) branches. 
E)  All statements are true. 
A)  Dextrans are bacterial and yeast polysaccharides. 
B)  All dextrans are made up of ($\alpha$1$\rightarrow$ 4)-linked poly-D-glucose. 
C)  All dextrans have ($\alpha$1$\rightarrow$ 3) branches. 
D)  Some dextrans have ($\alpha$1$\rightarrow$ 2) branches. 
E)  All statements are true.

Question 10

Which statement is NOT true regarding phosphorylated sugar?

Accepted Answer

A)  It is trapped inside the cell membrane. 
B)  It is relatively stable at neutral pH. 
C)  It is activated for subsequent chemical transformation 
D)  It can be a component of a nucleotide. 
E)  All of the statements are true. 
A)  It is trapped inside the cell membrane. 
B)  It is relatively stable at neutral pH. 
C)  It is activated for subsequent chemical transformation 
D)  It can be a component of a nucleotide. 
E)  All of the statements are true.

Question 11

A microarray of oligosaccharides can be used to determine:

Accepted Answer

A)  specificity of lectin binding. 
B)  affinity of lectin binding. 
C)  conformational flexibility of lectin binding. 
D)  both specificity and affinity of lectin binding. 
E)  both specificity and conformational flexibility of lectin binding. 
A)  specificity of lectin binding. 
B)  affinity of lectin binding. 
C)  conformational flexibility of lectin binding. 
D)  both specificity and affinity of lectin binding. 
E)  both specificity and conformational flexibility of lectin binding.

Question 12

When drawing a Haworth perspective formula from a Fisher projection, which statement is TRUE regarding anomers?

Accepted Answer

A)  It is $\alpha$ if the hydroxyl group on the anomeric carbon is up. 
B)  It is $\alpha$ if the hydroxyl group on the anomeric carbon is down 
C)  It is $\alpha$ if the hydroxyl group on the anomeric carbon on the same side of the ring as the C6 
D)  It is $\alpha$ if the hydroxyl group on the anomeric carbon on the opposite side of the ring as the C6 
E)  None of the answers is correct. 
A)  It is $\alpha$ if the hydroxyl group on the anomeric carbon is up. 
B)  It is $\alpha$ if the hydroxyl group on the anomeric carbon is down 
C)  It is $\alpha$ if the hydroxyl group on the anomeric carbon on the same side of the ring as the C6 
D)  It is $\alpha$ if the hydroxyl group on the anomeric carbon on the opposite side of the ring as the C6 
E)  None of the answers is correct.

Question 13

Describe the differences between a proteoglycan and a glycoprotein.

Accepted Answer

Proteoglycans and glycoproteins are both

Question 14

In the following structure:   (a) How many of the monosaccharide units are furanoses and how may are pyranoses? (b) What is the linkage between the two monosaccharide units? (c) Is this a reducing sugar?
Explain.

Accepted Answer

The answer of In the following structure:   (a)...

Question 15

Hemoglobin glycation is a process where _____ is _____ attached to hemoglobin.

Accepted Answer

A)  glycerol; covalently 
B)  glucose; enzymatically 
C)  glucose; nonenzymatically 
D)  N-acetyl-galactosamine; enzymatically 
E)  galactose; nonenzymatically 
A)  glycerol; covalently 
B)  glucose; enzymatically 
C)  glucose; nonenzymatically 
D)  N-acetyl-galactosamine; enzymatically 
E)  galactose; nonenzymatically

Question 16

Which statement about cellulose is TRUE?

Accepted Answer

A)  Cellulose is the main storage polysaccharide of animal cells. 
B)  Cellulose is a highly branched polysaccharide. 
C)  Cellulose is a homopolysaccharide. 
D)  Cellulose glucose residues contain the same configuration as amylose glucose residues. 
E)  Cellulose cannot be broken down by invertebrate animals. 
A)  Cellulose is the main storage polysaccharide of animal cells. 
B)  Cellulose is a highly branched polysaccharide. 
C)  Cellulose is a homopolysaccharide. 
D)  Cellulose glucose residues contain the same configuration as amylose glucose residues. 
E)  Cellulose cannot be broken down by invertebrate animals.

Question 17

In a(n) _____ the carbonyl group is at the end of the carbon chain, but in a(n) _____ the carbonyl group can be at any other position.

Accepted Answer

A)  aldose; ketose 
B)  ketose; aldose 
C)  hexose; heptose 
D)  aldose; hexose 
E)  ketose; tetrose 
A)  aldose; ketose 
B)  ketose; aldose 
C)  hexose; heptose 
D)  aldose; hexose 
E)  ketose; tetrose

Question 18

Why is it surprising that the side chains of tryptophan residues in lectins can interact with sugars?

Accepted Answer

A)  because the side chain of tryptophan is hydrophilic and sugars are hydrophobic 
B)  because the side chain of tryptophan is (-) charged and sugars are generally (+) charged or neutral 
C)  because the side chain of tryptophan can make hydrogen bonds and sugars cannot 
D)  because the side chain of tryptophan is hydrophobic and sugars are generally hydrophilic 
E)  None of the answers is correct. 
A)  because the side chain of tryptophan is hydrophilic and sugars are hydrophobic 
B)  because the side chain of tryptophan is (-) charged and sugars are generally (+) charged or neutral 
C)  because the side chain of tryptophan can make hydrogen bonds and sugars cannot 
D)  because the side chain of tryptophan is hydrophobic and sugars are generally hydrophilic 
E)  None of the answers is correct.

Question 19

Describe the structure of the repeating basic unit of (a) amylose and (b) cellulose.

Accepted Answer

The repeating basic unit of amylose is a

Question 20

_____ could be used to determine human blood group type.

Accepted Answer

A)  Lipopolysaccharides 
B)  Globoside 
C)  Glycoproteins 
D)  Lipoproteins 
E)  Mucins 
A)  Lipopolysaccharides 
B)  Globoside 
C)  Glycoproteins 
D)  Lipoproteins 
E)  Mucins

Exam 7: Carbohydrates and Glycobiology

Why is methyl iodide used in the classical method of exhaustive methylation to determine the positions of glycosidic bonds in a linear polysaccharide?

Define each in 20 words or fewer: (a) anomeric carbon (b) enantiomers (c) furanose (d) pyranose (e) glycoside (f) epimers (g) aldose (h) ketose

Explain why all mono- and disaccharides are soluble in water.

Which factor is NOT a part of determining the complete structure of an oligosaccharide or polysaccharide?

Which sequence is the CORRECT one for leukocyte extravasion in the inflammatory response?

It is useful to analyze hemoglobin glycation to determine a(n):

Which statement is FALSE about the enzyme lysozyme?

When two carbohydrates are epimers:

Which statement about dextrans is FALSE?

Which statement is NOT true regarding phosphorylated sugar?

A microarray of oligosaccharides can be used to determine:

When drawing a Haworth perspective formula from a Fisher projection, which statement is TRUE regarding anomers?

Describe the differences between a proteoglycan and a glycoprotein.

In the following structure: (a) How many of the monosaccharide units are furanoses and how may are pyranoses? (b) What is the linkage between the two monosaccharide units? (c) Is this a reducing sugar? Explain.

Hemoglobin glycation is a process where _____ is _____ attached to hemoglobin.

Which statement about cellulose is TRUE?

In a(n) _____ the carbonyl group is at the end of the carbon chain, but in a(n) _____ the carbonyl group can be at any other position.

Why is it surprising that the side chains of tryptophan residues in lectins can interact with sugars?

Describe the structure of the repeating basic unit of (a) amylose and (b) cellulose.

_____ could be used to determine human blood group type.

The Foundations of Biochemistry

Water

Amino Acids, Peptides, and Proteins

The Three-Dimensional Structure of Proteins

Protein Function

Enzymes

Nucleotides and Nucleic Acids

DNA-Based Information Technologies

Lipids

Biological Membranes and Transport

Biosignaling

Bioenergetics and Biochemical Reaction Types

Glycolysis, Gluconeogenesis, and the Pentose Phosphate Pathway

Principles of Metabolic Regulation

The Citric Acid Cycle

Fatty Acid Catabolism

Amino Acid Oxidation and the Production of Urea

Oxidative Phosphorylation and Photophosphorylation

Carbohydrate Biosynthesis in Plants and Bacteria

Lipid Biosynthesis

Biosynthesis of Amino Acids, Nucleotides, and Related Molecules

Hormonal Regulation and Integration of Mammalian Metabolism

Genes and Chromosomes

DNA Metabolism

RNA Metabolism

Protein Metabolism

Regulation of Gene Expression

Filters

Hemoglobin glycation is a process where _ is _ attached to hemoglobin.

In a(n) _ the carbonyl group is at the end of the carbon chain, but in a(n) _ the carbonyl group can be at any other position.