Question 1

Describe one biological advantage of storing glucose units in branched polymers (glycogen, amylopectin) rather than in linear polymers.

Accepted Answer

One biological advantage of storing gluc

Question 2

Which statement is NOT a reason that it is difficult to study oligosaccharide composition from biological systems?

Accepted Answer

A)  Oligosaccharides are often branched. 
B)  Oligosaccharides often have a high negative charge density. 
C)  Oligosaccharides have a variety of linkages . 
D)  Oligosaccharides have too much conformational flexibility. 
E)  There are no specific glycosidase enzymes that can be used to selectively digest oligosaccharides. 
A)  Oligosaccharides are often branched. 
B)  Oligosaccharides often have a high negative charge density. 
C)  Oligosaccharides have a variety of linkages . 
D)  Oligosaccharides have too much conformational flexibility. 
E)  There are no specific glycosidase enzymes that can be used to selectively digest oligosaccharides.

Question 3

The primary amino group of hemoglobin can react with glucose to form products that, downstream, generate advanced glycation end products (AGEs). Briefly explain why these AGEs are a problem in people with diabetes.

Accepted Answer

AGEs are a problem in people with diabet

Question 4

D-Glucose is called a reducing sugar because it undergoes an oxidation-reduction reaction at the anomeric carbon. One of the products of this reaction is:

Accepted Answer

A)  D-galactose. 
B)  D-gluconate. 
C)  D-glucuronate. 
D)  D-ribose. 
E)  muramic acid. 
A)  D-galactose. 
B)  D-gluconate. 
C)  D-glucuronate. 
D)  D-ribose. 
E)  muramic acid.

Question 5

To possess optical activity, a compound must be:

Accepted Answer

A)  a carbohydrate. 
B)  a hexose. 
C)  asymmetric. 
D)  colored. 
E)  D-glucose. 
A)  a carbohydrate. 
B)  a hexose. 
C)  asymmetric. 
D)  colored. 
E)  D-glucose.

Question 6

In most cases, in order for an informational carbohydrate to become a biologically active molecule, it must:

Accepted Answer

A)  be an asymmetric molecule. 
B)  contain a reducing sugar. 
C)  contain an O-glycosidic bond. 
D)  be covalently joined to a protein or lipid. 
E)  be present in the extracellular matrix. 
A)  be an asymmetric molecule. 
B)  contain a reducing sugar. 
C)  contain an O-glycosidic bond. 
D)  be covalently joined to a protein or lipid. 
E)  be present in the extracellular matrix.

Question 7

In glycoproteins, the carbohydrate moiety is always attached through the amino acid residues:

Accepted Answer

A)  asparagine, serine, or threonine. 
B)  aspartate or glutamate. 
C)  glutamine or arginine. 
D)  glycine, alanine, or aspartate. 
E)  tryptophan, aspartate, or cysteine. 
A)  asparagine, serine, or threonine. 
B)  aspartate or glutamate. 
C)  glutamine or arginine. 
D)  glycine, alanine, or aspartate. 
E)  tryptophan, aspartate, or cysteine.

Question 8

Why does the cyclization of sugars create an additional chiral center in that molecule? What is the nomenclature of the stereoisomer produced by this reaction?

Accepted Answer

The cyclization of sugars creates an add

Question 9

Which commonality does NOT exist between peptides, nucleic acids, and poly- and oligosaccharides?

Accepted Answer

A)  They are all synthesized from a template. 
B)  They are all information-carrying molecules. 
C)  They are all created from multiple building blocks. 
D)  The sequence of monomers is important for function. 
E)  All of the answer choices are commonalities between peptides, nucleic acids, and poly- and oligosaccharides. 
A)  They are all synthesized from a template. 
B)  They are all information-carrying molecules. 
C)  They are all created from multiple building blocks. 
D)  The sequence of monomers is important for function. 
E)  All of the answer choices are commonalities between peptides, nucleic acids, and poly- and oligosaccharides.

Question 10

Why are ruminant animals like cows able to digest cellulose?

Accepted Answer

A)  Their teeth are able to grind the polysaccharide into smaller saccharides. 
B)  Their stomachs secrete the enzyme cellulose. 
C)  They have a stomach compartment that houses symbiotic microorganisms that can hydrolyze cellulose. 
D)  Their small intestine contains an environment suitable to hydrolyze cellulose. 
E)  All animals can digest cellulose. 
A)  Their teeth are able to grind the polysaccharide into smaller saccharides. 
B)  Their stomachs secrete the enzyme cellulose. 
C)  They have a stomach compartment that houses symbiotic microorganisms that can hydrolyze cellulose. 
D)  Their small intestine contains an environment suitable to hydrolyze cellulose. 
E)  All animals can digest cellulose.

Question 11

Briefly explain the procedure involved in using an oligosaccharide microarray to identify the binding specificity for a potential lectin.

Accepted Answer

An oligosaccharide microarray is a high-

Question 12

What is the biological advantage to an organism that stores its carbohydrate reserves as starch or glycogen rather than as an equivalent amount of free glucose?

Accepted Answer

Storing carbohydrate reserves as starch

Question 13

Which monosaccharide is NOT a six-carbon monosaccharide?

Accepted Answer

A)  fructose 
B)  ribose 
C)  mannose 
D)  glucose 
E)  galactose 
A)  fructose 
B)  ribose 
C)  mannose 
D)  glucose 
E)  galactose

Question 14

Which glycosaminoglycan is found in the synovial fluid of joints?

Accepted Answer

A)  chondroitin sulfate 
B)  dermatan sulfate 
C)  hyaluronan 
D)  keratin sulfate 
E)  heparan sulfate 
A)  chondroitin sulfate 
B)  dermatan sulfate 
C)  hyaluronan 
D)  keratin sulfate 
E)  heparan sulfate

Question 15

Which compound is a heteropolysaccharide?

Accepted Answer

A)  cellulose 
B)  chitin 
C)  glycogen 
D)  hyaluronate 
E)  starch 
A)  cellulose 
B)  chitin 
C)  glycogen 
D)  hyaluronate 
E)  starch

Question 16

The two monosaccharides shown below could BEST be described as:

Accepted Answer

A)  ketoses. 
B)  anomers. 
C)  rotamers. 
D)  epimers. 
E)  enantiomers. 
A)  ketoses. 
B)  anomers. 
C)  rotamers. 
D)  epimers. 
E)  enantiomers.

Question 17

Which pair is anomeric?

Accepted Answer

A)  D-glucose and D-fructose 
B)  D-glucose and L-fructose 
C)  D-glucose and L-glucose 
D)  $\alpha$-D-glucose and$\beta$-D-glucose 
E)  $\alpha$-D-glucose and $\beta$-L-glucose 
A)  D-glucose and D-fructose 
B)  D-glucose and L-fructose 
C)  D-glucose and L-glucose 
D)  $\alpha$-D-glucose and$\beta$-D-glucose 
E)  $\alpha$-D-glucose and $\beta$-L-glucose

Question 18

Which statement about starch and glycogen is FALSE?

Accepted Answer

A)  Amylose is unbranched; amylopectin and glycogen contain many ($\alpha$1$\rightarrow$ 6) branches. 
B)  Both are homopolymers of glucose. 
C)  Both serve primarily as structural elements in cell walls. 
D)  Both starch and glycogen are stored intracellularly as insoluble granules. 
E)  Glycogen is more extensively branched than starch. 
A)  Amylose is unbranched; amylopectin and glycogen contain many ($\alpha$1$\rightarrow$ 6) branches. 
B)  Both are homopolymers of glucose. 
C)  Both serve primarily as structural elements in cell walls. 
D)  Both starch and glycogen are stored intracellularly as insoluble granules. 
E)  Glycogen is more extensively branched than starch.

Question 19

Which statement is FALSE regarding proteoglycans?

Accepted Answer

A)  Both syndecans and glypicans can be shed into the extracellular space. 
B)  Proteoglycan shedding is unregulated in cells. 
C)  A protease or phospholipase is responsible for releasing proteoglycans. 
D)  Proteoglycan shedding is activated in cancerous cells. 
E)  Cell features such as proteoglycans can be changed quickly. 
A)  Both syndecans and glypicans can be shed into the extracellular space. 
B)  Proteoglycan shedding is unregulated in cells. 
C)  A protease or phospholipase is responsible for releasing proteoglycans. 
D)  Proteoglycan shedding is activated in cancerous cells. 
E)  Cell features such as proteoglycans can be changed quickly.

Question 20

Explain how it is possible that a polysaccharide molecule, such as glycogen, may have only one reducing end, and yet have many nonreducing ends.

Accepted Answer

Polysaccharide molecules, such as glycog

Exam 7: Carbohydrates and Glycobiology

Describe one biological advantage of storing glucose units in branched polymers (glycogen, amylopectin) rather than in linear polymers.

Which statement is NOT a reason that it is difficult to study oligosaccharide composition from biological systems?

The primary amino group of hemoglobin can react with glucose to form products that, downstream, generate advanced glycation end products (AGEs). Briefly explain why these AGEs are a problem in people with diabetes.

D-Glucose is called a reducing sugar because it undergoes an oxidation-reduction reaction at the anomeric carbon. One of the products of this reaction is:

To possess optical activity, a compound must be:

In most cases, in order for an informational carbohydrate to become a biologically active molecule, it must:

In glycoproteins, the carbohydrate moiety is always attached through the amino acid residues:

Why does the cyclization of sugars create an additional chiral center in that molecule? What is the nomenclature of the stereoisomer produced by this reaction?

Which commonality does NOT exist between peptides, nucleic acids, and poly- and oligosaccharides?

Why are ruminant animals like cows able to digest cellulose?

Briefly explain the procedure involved in using an oligosaccharide microarray to identify the binding specificity for a potential lectin.

What is the biological advantage to an organism that stores its carbohydrate reserves as starch or glycogen rather than as an equivalent amount of free glucose?

Which monosaccharide is NOT a six-carbon monosaccharide?

Which glycosaminoglycan is found in the synovial fluid of joints?

Which compound is a heteropolysaccharide?

The two monosaccharides shown below could BEST be described as:

Which pair is anomeric?

Which statement about starch and glycogen is FALSE?

Which statement is FALSE regarding proteoglycans?

Explain how it is possible that a polysaccharide molecule, such as glycogen, may have only one reducing end, and yet have many nonreducing ends.

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

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