Question 1

Which of the following statements is NOT correct regarding cyclic sugars?

Accepted Answer

A) The a-anomer has the -OH of the anomeric carbon positioned on the opposite side of the sugar ring from the -CH₂OH. 
B) The 5- and 6-membered rings are more frequently observed due to stability. 
C) In a chair conformation,the predominant form has the bulkiest substituents occupying axial positions. 
D) They can be formed by the intramolecular reactions to hemiacetals or hemiketals. 
A) The a-anomer has the -OH of the anomeric carbon positioned on the opposite side of the sugar ring from the -CH₂OH. 
B) The 5- and 6-membered rings are more frequently observed due to stability. 
C) In a chair conformation,the predominant form has the bulkiest substituents occupying axial positions. 
D) They can be formed by the intramolecular reactions to hemiacetals or hemiketals.

Question 2

Neither α-amylase nor β-amylase can cleave the α(1→6)glycosidic bonds of amylopectin.Which of the following enzymes is required to completely hydrolyze starch?

Accepted Answer

A) α(1→6)-glucosidase 
B) glycogen phosphorylase 
C) maltase 
D) sucrase 
A) α(1→6)-glucosidase 
B) glycogen phosphorylase 
C) maltase 
D) sucrase

Question 3

Which of the following represents an example of a proteoglycan?

Accepted Answer

A) attachment of several molecules of heparin to the peptide antithrombin III 
B) attachment of a Gal-β(1,3)-GalNAc disaccharide to the fish antifreeze protein 
C) attachment of a small oligosaccharide to an immunoglobulin 
D) attachment of a small antigenic determinant to a membrane-bound protein of a cell 
A) attachment of several molecules of heparin to the peptide antithrombin III 
B) attachment of a Gal-β(1,3)-GalNAc disaccharide to the fish antifreeze protein 
C) attachment of a small oligosaccharide to an immunoglobulin 
D) attachment of a small antigenic determinant to a membrane-bound protein of a cell

Question 4

In plant cells,starch is hydrolyzed by starch phosphorylase.Which of the following is released upon hydrolysis?

Accepted Answer

A) glucose-1-phosphate and a starch molecule with 1 less glucose unit 
B) glucose-6-phosphate and a starch molecule with 1 less glucose unit 
C) maltose-1-phosphate and a starch molecule with 2 less glucose units 
D) maltose-6-phosphate and a starch molecule with 2 less glucose units 
A) glucose-1-phosphate and a starch molecule with 1 less glucose unit 
B) glucose-6-phosphate and a starch molecule with 1 less glucose unit 
C) maltose-1-phosphate and a starch molecule with 2 less glucose units 
D) maltose-6-phosphate and a starch molecule with 2 less glucose units

Question 5

Which of the following disaccharides contains an a(14)O-glycosidic bond?

Accepted Answer

A) sucrose 
B) lactose 
C) maltose 
D) cellobiose 
A) sucrose 
B) lactose 
C) maltose 
D) cellobiose

Question 6

Which of the following statements explains why cooked starch is more digestible than uncooked starch?

Accepted Answer

A) It has been partially hydrolyzed during cooking. 
B) The amylopectin is converted to amylose during cooking. 
C) The enzymes that hydrolyze the starch are active only when the starch is hot. 
D) The starch granules take up water,swell,and are more accessible to the enzymes. 
A) It has been partially hydrolyzed during cooking. 
B) The amylopectin is converted to amylose during cooking. 
C) The enzymes that hydrolyze the starch are active only when the starch is hot. 
D) The starch granules take up water,swell,and are more accessible to the enzymes.

Question 7

Which of the following enzymes is found in liver and muscle tissue and is used to catalyze the hydrolysis of glycogen to glucose-1-phosphate?

Accepted Answer

A) glycogen phosphorylase 
B) β(1→6)-glucosidase 
C) α-amylase 
D) glycogen maltase 
A) glycogen phosphorylase 
B) β(1→6)-glucosidase 
C) α-amylase 
D) glycogen maltase

Question 8

Which of the following are important components of the vitreous humour of the eye and of synovial fluid that lubricates the joints?

Accepted Answer

A) heparins 
B) hyaluronates 
C) chondroitins 
D) keratin sulfates 
A) heparins 
B) hyaluronates 
C) chondroitins 
D) keratin sulfates

Question 9

Which of the following sugars is NOT a homodisaccharide?

Accepted Answer

A) lactose 
B) maltose 
C) isomaltose 
D) cellobiose 
A) lactose 
B) maltose 
C) isomaltose 
D) cellobiose

Question 10

If carbon 1 is the carbonyl group of an aldohexose,which of the following carbons determines if the sugar is a D- or an L-stereoisomer?

Accepted Answer

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

Question 11

Which of the following pair of glycosamines is linked to 3-carbon acids at the C-1 or C-3 positions,and are components of the polysaccharides of higher organisms and bacterial cell walls?

Accepted Answer

A) glucosides and galactosides 
B) muramic acid and neuraminic acid 
C) gluconic acid and glucuronic acid 
D) sorbitol and ribitol 
A) glucosides and galactosides 
B) muramic acid and neuraminic acid 
C) gluconic acid and glucuronic acid 
D) sorbitol and ribitol

Question 12

Which of the following is a characteristicof cellulose fibre?

Accepted Answer

A) It is a linear polymer of β(1→4)glycosidic-linked glucose and galactose residues. 
B) It is extremely susceptible to hydrolysis. 
C) It is made up of very weak microfibrils. 
D) Intermolecular hydrogen bonds play a major role in the stabilization of microfibrils. 
A) It is a linear polymer of β(1→4)glycosidic-linked glucose and galactose residues. 
B) It is extremely susceptible to hydrolysis. 
C) It is made up of very weak microfibrils. 
D) Intermolecular hydrogen bonds play a major role in the stabilization of microfibrils.

Question 13

Which of the following pairs of molecules is found in tendons,cartilage,and other connective tissue?

Accepted Answer

A) heparin and chondroitins 
B) chondroitins and keratin sulfate 
C) keratin sulfate and dermatan sulfate 
D) hyaluronate and keratin sulfate 
A) heparin and chondroitins 
B) chondroitins and keratin sulfate 
C) keratin sulfate and dermatan sulfate 
D) hyaluronate and keratin sulfate

Question 14

?-D-Glucopyranose in the chair form is the most widely occurring form of glucose in nature.Which of the following is one of its characteristics?

Accepted Answer

A) The anomeric carbon has a hydroxyl that is below the plane of the chair. 
B) It forms a 5-membered ring. 
C) Carbon 6 is below the plane of the chair. 
D) All the -OH groups are equatorial. 
A) The anomeric carbon has a hydroxyl that is below the plane of the chair. 
B) It forms a 5-membered ring. 
C) Carbon 6 is below the plane of the chair. 
D) All the -OH groups are equatorial.

Question 15

Which of the following sugars is commonly referred to as cellulose?

Accepted Answer

A) (1→4)-α-D-mannopyranan 
B) (1→4)-β-D-glucopyranan 
C) (1→6)-α-D-mannopyranan 
D) (1→6)-α-D-glucopyranan 
A) (1→4)-α-D-mannopyranan 
B) (1→4)-β-D-glucopyranan 
C) (1→6)-α-D-mannopyranan 
D) (1→6)-α-D-glucopyranan

Question 16

Which of the following does NOT apply to both cellulose and chitin?

Accepted Answer

A) Both are polymers of glucose. 
B) Both are structural polysaccharides. 
C) Both have extended ribbon conformations. 
D) Both have extensive hydrogen bonding. 
A) Both are polymers of glucose. 
B) Both are structural polysaccharides. 
C) Both have extended ribbon conformations. 
D) Both have extensive hydrogen bonding.

Question 17

Glycosaminoglycans are unbranched polysaccharides consisting of alternating residues of uronic acid and hexosamine.Which of the following is NOT a glycosaminoglycan?

Accepted Answer

A) agaropectin 
B) heparin 
C) dermatan sulfate 
D) hyaluronate 
A) agaropectin 
B) heparin 
C) dermatan sulfate 
D) hyaluronate

Question 18

Which of the following alcohols is NOT a sugar alcohol?

Accepted Answer

A) ribitol 
B) sorbitol 
C) glycerol 
D) mannitol 
A) ribitol 
B) sorbitol 
C) glycerol 
D) mannitol

Question 19

Individuals with uncontrolled diabetes mellitus may have elevated levels of blood glucose.As a result of this,which of the following is their blood normally tested for?

Accepted Answer

A) reducing sugars 
B) oxidizing sugars 
C) fructose 
D) gluconic acid 
A) reducing sugars 
B) oxidizing sugars 
C) fructose 
D) gluconic acid

Question 20

Which of the following disaccharides is NOT a reducing sugar?

Accepted Answer

A) lactose 
B) maltose 
C) sucrose 
D) cellulose 
A) lactose 
B) maltose 
C) sucrose 
D) cellulose

Exam 7: Carbohydrates and the Glycoconjugates of Cell Surfaces

Which of the following statements is NOT correct regarding cyclic sugars?

Neither α-amylase nor β-amylase can cleave the α(1→6)glycosidic bonds of amylopectin.Which of the following enzymes is required to completely hydrolyze starch?

Which of the following represents an example of a proteoglycan?

In plant cells,starch is hydrolyzed by starch phosphorylase.Which of the following is released upon hydrolysis?

Which of the following disaccharides contains an a(14)O-glycosidic bond?

Which of the following statements explains why cooked starch is more digestible than uncooked starch?

Which of the following enzymes is found in liver and muscle tissue and is used to catalyze the hydrolysis of glycogen to glucose-1-phosphate?

Which of the following are important components of the vitreous humour of the eye and of synovial fluid that lubricates the joints?

Which of the following sugars is NOT a homodisaccharide?

If carbon 1 is the carbonyl group of an aldohexose,which of the following carbons determines if the sugar is a D- or an L-stereoisomer?

Which of the following pair of glycosamines is linked to 3-carbon acids at the C-1 or C-3 positions,and are components of the polysaccharides of higher organisms and bacterial cell walls?

Which of the following is a characteristicof cellulose fibre?

Which of the following pairs of molecules is found in tendons,cartilage,and other connective tissue?

?-D-Glucopyranose in the chair form is the most widely occurring form of glucose in nature.Which of the following is one of its characteristics?

Which of the following sugars is commonly referred to as cellulose?

Which of the following does NOT apply to both cellulose and chitin?

Glycosaminoglycans are unbranched polysaccharides consisting of alternating residues of uronic acid and hexosamine.Which of the following is NOT a glycosaminoglycan?

Which of the following alcohols is NOT a sugar alcohol?

Individuals with uncontrolled diabetes mellitus may have elevated levels of blood glucose.As a result of this,which of the following is their blood normally tested for?

Which of the following disaccharides is NOT a reducing sugar?

The Facts of Life: Chemistry Is the Logic of Biological Phenomena

Water: the Medium of Life

Thermodynamics of Biological Systems

Amino Acids

Proteins: Their Primary Structure and Biological Functions

Proteins: Secondary, tertiary, and Quaternary Structure

Lipids

Lipid Biosynthesis

Membranes and Membrane Transport

The Reception and Transmission of Extracellular Information

Enzymes Kinetics and Specificity

Mechanisms of Enzyme Action

Enzyme Regulation

Molecular Motors

Nutrition and the Organization of Metabolism

Glycolysis

The Tricarboxylic Acid Cycle

Electron Transport and Oxidative Phosphorylation

Photosynthesis

Gluconeogenesis, glycogen Metabolism, and the Pentose Phosphate Pathway

Fatty Acid Catabolism

Nitrogen Acquisition and Amino Acid Metabolism

Nucleotides and Nucleic Acids

Structure of Nucleic Acids

Synthesis and Degradation of Nucleotides

Recombinant Dna: Cloning and Creation of Chimeric Genes

DNA Metabolism: Replication, recombination, and Repair

Transcription and the Regulation of Gene Expression

Protein Synthesis

Post-Transcriptional Regulation of Gene Expression

Completing the Protein Life Cycle: Folding, processing, and Degradation

Metabolic Integration and Organ Specialization

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