Question 1

In aldohexoses,it is the -OH group on C5 that reacts with the aldehyde carbonyl to form two cyclic hemiacetals called anomers.

Accepted Answer

A) True 
 B)False  True

Question 2

Carbohydrates that are oxidized with Benedict's reagent are called reducing sugars,because they reduce the Cu2+ in Benedict's reagent to Cu+ during the reaction.

Accepted Answer

A) True 
 B)False  True

Question 3

In the monosaccharide given,which of the labeled carbons are chiral centers?

Accepted Answer

A) C1 is the only chiral center. 
B) C1 and C2 are both chiral centers. 
C) C2 and C3 are both chiral centers 
D) C3 is the only chiral center 
A) C1 is the only chiral center. 
B) C1 and C2 are both chiral centers. 
C) C2 and C3 are both chiral centers 
D) C3 is the only chiral center C

Question 4

How many chirality centers are present in the compound shown below?

Accepted Answer

A) 2 
B) 4 
C) 5 
D) 6 
A) 2 
B) 4 
C) 5 
D) 6

Question 5

Which statement concerning carbohydrates is incorrect?

Accepted Answer

A) Carbohydrates serve important energy and structural roles for both plants and animals. 
B) Monosaccharides are the simplest carbohydrates and are known as simple sugars. 
C) Humans store excess glucose for short term energy requirements in the polysaccharide cellulose. 
D) Carbohydrates that can be oxidized by Benedict's reagent are called reducing sugars. 
A) Carbohydrates serve important energy and structural roles for both plants and animals. 
B) Monosaccharides are the simplest carbohydrates and are known as simple sugars. 
C) Humans store excess glucose for short term energy requirements in the polysaccharide cellulose. 
D) Carbohydrates that can be oxidized by Benedict's reagent are called reducing sugars.

Question 6

How many chirality centers are present in the compound shown below?

Accepted Answer

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

Question 7

A hemiacetal is a compound that contains a hydroxyl group (-OH)and an alkoxy group (-OR)on adjacent carbon atoms.

Accepted Answer

A) True 
 B)False

Question 8

All carbohydrates,except for dihydroxyacetone,contain one or more chirality centers.

Accepted Answer

A) True 
 B)False

Question 9

What is the classification of the monosaccharide shown?

Accepted Answer

A) L 
B) D 
C) A sugar this large is not classified as L or D. 
A) L 
B) D 
C) A sugar this large is not classified as L or D.

Question 10

The disaccharide shown below has an α-glycosidic linkage.

Accepted Answer

A) True 
 B)False

Question 11

Carbohydrates are structurally defined as polyhydroxyaldehydes and polyhydroxyketones,or compounds that can be hydrolyzed to them.

Accepted Answer

A) True 
 B)False

Question 12

The two monosaccharides shown below are related as enantiomers.

Accepted Answer

A) True 
 B)False

Question 13

The structure shown has four (4)chirality centers and is a D monosaccharide.

Accepted Answer

A) True 
 B)False

Question 14

Individuals who are lactose intolerant no longer produce the enzyme ________.

Accepted Answer

The answer of Individuals who are lactose intolerant no longer...

Question 15

All aldoses and ketoses are reducing sugars.

Accepted Answer

A) True 
 B)False

Question 16

Certain monosaccharides-notably aldopentoses and ketohexoses-form five-membered rings,not six-membered rings,in solution.

Accepted Answer

A) True 
 B)False

Question 17

What is the difference between the disaccharides lactose and maltose?

Accepted Answer

A) Lactose contains two glucose units,while maltose contains two galactose units. 
B) The two monosaccharides in lactose are joined by a 1→4-β-glycoside bond,while the two monosaccharides in maltose are joined by a 1→4-α-glycoside bond. 
C) Lactose contains both an acetal and a hemiacetal,while maltose contains two acetals. 
D) Lactose can be hydrolyzed in the body,but maltose cannot. 
A) Lactose contains two glucose units,while maltose contains two galactose units. 
B) The two monosaccharides in lactose are joined by a 1→4-β-glycoside bond,while the two monosaccharides in maltose are joined by a 1→4-α-glycoside bond. 
C) Lactose contains both an acetal and a hemiacetal,while maltose contains two acetals. 
D) Lactose can be hydrolyzed in the body,but maltose cannot.

Question 18

The β anomer of a cyclic monosaccharide has the -OH group drawn down,below the ring.

Accepted Answer

A) True 
 B)False

Question 19

All disaccharides contain at least one acetal that joins the rings together.

Accepted Answer

A) True 
 B)False

Question 20

What is the classification of the compound shown below?

Accepted Answer

A) A tetraketose 
B) A ketotriose 
C) A ketotetrose 
D) An aldotriose 
A) A tetraketose 
B) A ketotriose 
C) A ketotetrose 
D) An aldotriose

Exam 20: Carbohydrates

In aldohexoses,it is the -OH group on C5 that reacts with the aldehyde carbonyl to form two cyclic hemiacetals called anomers.

Carbohydrates that are oxidized with Benedict's reagent are called reducing sugars,because they reduce the Cu2+ in Benedict's reagent to Cu+ during the reaction.

In the monosaccharide given,which of the labeled carbons are chiral centers?

How many chirality centers are present in the compound shown below?

Which statement concerning carbohydrates is incorrect?

How many chirality centers are present in the compound shown below?

A hemiacetal is a compound that contains a hydroxyl group (-OH)and an alkoxy group (-OR)on adjacent carbon atoms.

All carbohydrates,except for dihydroxyacetone,contain one or more chirality centers.

What is the classification of the monosaccharide shown?

The disaccharide shown below has an α-glycosidic linkage.

Carbohydrates are structurally defined as polyhydroxyaldehydes and polyhydroxyketones,or compounds that can be hydrolyzed to them.

The two monosaccharides shown below are related as enantiomers.

The structure shown has four (4)chirality centers and is a D monosaccharide.

Individuals who are lactose intolerant no longer produce the enzyme ________.

All aldoses and ketoses are reducing sugars.

Certain monosaccharides-notably aldopentoses and ketohexoses-form five-membered rings,not six-membered rings,in solution.

What is the difference between the disaccharides lactose and maltose?

The β anomer of a cyclic monosaccharide has the -OH group drawn down,below the ring.

All disaccharides contain at least one acetal that joins the rings together.

What is the classification of the compound shown below?

Matter and Measurement

Atoms and the Periodic Table

Ionic Compounds

Covalent Compounds

Chemical Reactions

Energy Changes,reaction Rates,and Equilibrium

Gases,liquids,and Solids

Solutions

Acids and Bases

Nuclear Chemistry

Introduction to Organic Molecules and Functional Groups

Alkanes

Unsaturated Hydrocarbons

Organic Compounds That Contain Oxygen,halogen,or Sulfur

The Three-Dimensional Shape of Molecules

Aldehydes and Ketones

Carboxylic Acids,esters,and Amides

Amines and Neurotransmitters

Lipids

Amino Acids,proteins,and Enzymes

Nucleic Acids and Protein Synthesis

Metabolism and Energy Production

Carbohydrate,lipid,and Protein Metabolism

Filters

Carbohydrates that are oxidized with Benedict's reagent are called reducing sugars,because they reduce the Cu²⁺ in Benedict's reagent to Cu⁺ during the reaction.