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1 . The minimum number of carbon atoms that should be present in a monosaccharite is :

(A) 2 (B) 3 (C) 4 (D) 6

2 . Carbohydrates that, on attempted hydrolysis, are not cleaved to smaller carbohydrates are called :

(A) oligosaccharides (B) polysaccharides (C) disaccharides (D) monosaccharides

3 . The IUPAC name of the ketotriose is :

(A) 1, 3-dihydroxypropanone (B) 1-3-dihydroxy-2-oxopropane

(C) 2-oxo-1, 3-propanediol (C) dihydroxyacetone

4 . The number of chiral centres in the open chain structure of glucose is :

(A) 3 (B) 4 (C) 5 (D) 6

5 . Cane sugar on hydrolysis gives :

(A) glucose and galactose (B) glucose and fructose

(C) glucose only (D) fructose only

6 . In D-erythrose, the configurations at C-2 and C-3 are respectively :

(A) 2R, 3R (B) 2S, 3S (C) 2R, 3S (D) 2S, 3R

7 . Glucose and fructose are :

(A) diastereomers (B) anomers (C) epimers (D) functional isomers

8 . Which of the following structures represents -D-glucopyranose?

(A)

HOCH2O

OH

HO

HOOH (B)

HOCH2OOH

OH

HOOH (C)

HOCH2O

OHHO

OH

HO (D)

HOCH2O

OHHO

OHOH

9 . Sorbitol can be obtained by the reduction of -

(A) sorbose (B) glucose (C) fructose (D) all of these

1 0 . Freshly prepared solution of cane sugar, under the influence of acid catalyst, undergoes change in optical

rotation with laps of time. This phenomenon is called -

(A) mutarotation (B) inversion

(C) racemization (D) optical rotatory dispersion

1 1 . In the formation of osazone derivatives of aldohexoses and ketohexoses, the carbon atom (s) that participate

(s) in the reactions is -

(A) C-1 (B) C-2 (C) C-1 and C-2 (D) C-2 and C-3

1 2 . Glucose gives positive silver mirror test with ammoniacal silver nitrate because it contains -

(A) hydroxyl group (B) aldehyde group

(C) ketone group (D) vicinal diol group

1 3 . Fructose reduces fehling's solution due to the presence of -

(A) hydroxy group (B) aldehyde group

(C) ketone group (D) -hydroxyketone group

EXERCISE-01 CHECK YOUR GRASP

SELECT THE CORRECT ALTERNATIVE (ONLY ONE CORRECT ANSWER)

1 4 . In the multi-step conversion of an aldose into next higher aldose by Kiliani-Fischer synthesis, the reagent

employed in the first step is -

(A) C6H5NHNH2 (B) NH2OH (C) Br2/H2O (D) HCN

1 5 . When methyl D-Glucopyranoside is oxidized with periodic acid, how many moles of the oxidizing agent are

consumed per mole of the sugar ?

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

1 6 . -D-glucose is represented as -

(A)

HO OH

HO OHHO

O(B)

HOOH

HO OHHO

O(C)

HO OH

HO

OHHO

O

(D)HO

OH

HO OH

OOH

1 7 . The number of carbon atoms and oxygen atoms present in the ring of the D-glucopyranose are respectively:

(A) 5 and 1 (B) 4 and 1 (C) 4 and 2 (D) 3 and 2

1 8 . Glucose is oxidized by nitric acid to give

(A) gluconic acid (B) glucaric acid (C) glucuronic acid (D) glycolic acid

1 9 . D-()- Erythrose and D-()- threose are separately reduced with NaBH4 to give the products (A) and (B)

respectively. Which of the following statements is correct about (A) and (B) ?

(A) Both (A) and (B) will be optically active.

(B) Both (A) and (B) will be optically inactive.

(C) (A) will be optically inactive but (B) will be optically active

(D) Neither (A) not (B) possesses any asymmetric carbon atom.

2 0 . The products expected from the reaction are :

CHO

CH2

H C OH

HCOH

CHOH22-Deoxy-D-ribose

HIO4

(excess)

(A) OHCCH2CHO, HCOOH and HCHO (B) HOOCCHOHCHOHCOOH and HCOOH

(B) HOOCCH2COOH, HCOOH and HCHO (D) HOOCCOOH, HCOOH and HCHO

2 1 . Glucose does not react with

(A) C6H5NHNH2 (B) NH2OH (C) HCN (D) NaHSO3

2 2 . Which one among the following is a peptide linkage ?

(A) CN

O H

(B) CON

R H

(C) C=NH

R

(D) N=CO

R

2 3 . The pH at which an amino acids carries no net charge is called its :

(A) isoelectric point (B) Inversion point (C) Neutralization point (D) triple point

2 4 . The configurations of the compounds I and II

COOH COOH

H HNH2 NH2

CH3 CHSH2

I II

are respectively

(A) R and R (B) R and S (C) S and S (D) S and R

2 5 . Consider the following sequence of reactions.

C

C

NK

O

O

2 2 2 2

2 25

1. BrCH (CO Et ) 1. PhCH Cl

2. C H ONa 2. HCl, H O, heatA B

The major final product (B) is

(A) H2NCH2COOH (B) PhCH(NH2)COOH

(C) PhCH2CH(NH2)COOH (D) PhCHC(COOEt)2 2

NH2

CHECK YOUR GRASP EXERCISE -1ANSWER KEYQ u e . 1 2 3 4 5 6 7 8 9 10 1 1 1 2 1 3 1 4 1 5 1 6 1 7 1 8 19 2 0

An s . B D A B B A D A D B C B D D A A A B C A

Q u e . 2 1 2 2 2 3 24 25

An s . D A A B C

SELECT THE CORRECT ALTERNATIVES (ONE OR MORE THEN ONE CORRECT ANSWERS)

1 . Which of the following carbohydrates is a disaccharide?

(A) Glucose (B) Fructose (C) Maltose (D) Lactose

2 . -D-Glucopyranose and -D-glucopyranose are :

(A) Anomer (B) Epimer (C) Diastereomers (D) enantiomers

3 . Consider the following structures.

H H HO HOHO HO H HHO H H HOH OH OH H

H H OH OHOH OH H H

C=O C=O C=O C=O

CHOH2 CHOH2 CHOH2 CHOH2

CHOH2 CHOH2 CHOH2 CHOH2

I II III IV

Which of the following pairs represent D- and L-fructose respectively?

(A) II and I (B) I and III (C) III and IV (D) II and IV

4 . (+) - sucrose is made up of -

(A) D-glucose and L-fructose (B) D-glucose and D-frucotse

(C) D-fructose and L-glucose (D) L-fructose and L-glucose

5 . Glucose cannot be classified as -

(A) a carbohydrate (B) a hexose

(C) an aldose (D) an oligosaccharide

6 . D-Glucose and D-mannose are -

(A) anomers (B) epimers (C) diastereomers (D) enantiomers

7 . D-Glucose reacts with anhydrous methyl alcohol in the presence of dry HCl gas to form -

(A) 2,3,4,5,6-penta-O-methyl D-glucose (B) -methyl D-glucopyranoside

(C) -methyl D-glucopyranoside (D) Both (B) and (C)

8 . When glucose is treated with an excess of HIO4, the products formed are -

(A) one mole of glyoxal (CHOCHO), one mole of HCHO and three moles of HCOOH

(B) five moles of HCOOH and one mole of HCOH

(C) one mole of oxalic acid (COOHCOOH), three moles of HCOOH and one mole of HCHO

(D) six moles of HCOOH

9 . Methyl D-glucoside on reaction with HIO4 consume two moles of the reagent and produces the dialdehyde

(A) and one mole of HCOOH :

HOCHCHOCHO2 CH3

CHOCHO

The result of this reaction proves that glucose has :

(A) a pyranose structure (B) a furanose structure

(C) an open-chain structure (D) a four-membered ring structure

EXERCISE02 BRAIN TEASERS

1 0 . Following are the structure of D-glucose and D-galactose-

CHO CHO

CHOH2 CHOH2

H H

H HO

H H

OH HO

OH H

OH OH

H H

OH OH

D-Glucose D-Galactose

which of the statement is correct about these compounds :

(A) They are diastereomers (B) both are components of lactose

(C) They are C-4 epimers (D) they are enantiomers

1 1 . D-Glucose is treated with an excess of acetic anhydride in the presence of pyridine. Identify the products

formed.

(A)

CHO

CHOAc2

H

H

H

AcO

OAc

OAc

H

OAc

(B)

O

OAcOAc

AcO

OAc

CHOAc2

(C)

O OAc

OAcAcO

OAc

CHOAc2

(D)

CHO

CHOAc2

H

H

H

AcO

OAc

OAc

H

OAc

1 2 . The product formed in the reaction is :

6 5 2C H NHNH6 5 6 5

(excess )C H CHOHCOC H

(A)

CH6 5

CHOH

C

CH6 5 NNHCH6 5

(B)

CH6 5

C

C

CH6 5 NNHCH6 5

NNHCH6 5

(C)

CH6 5

C

C

CH6 5 O

O

(D)

CH6 5

CH

CH

CH6 5 OH

OH

1 3 . (+)-Sucrose has a specific rotation of +66.5, while D-(+)-glucose and D-()-fructose have specific rotations

of +52.5 and 92.4 respectively. After complete hydrolysis of (+)surcose by dilute acid, what will be the

specific rotation of the hydrolysis product, called invert sugar [a 1 : 1 mixture of D-(+)-glucose and

D-()-fructose]?

(A) 39.9 (B) 72.4 (C) 19.9 (D) 34.9

Qu e. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

An s . C, D A,B,C C B D B,C D B A A,B,C B,C B C A,C,D A,B,C

Qu e. 16 17 18 19 20

An s . C D A,B,D D A,B,C

BRAIN TEASERS EXERCISE -2ANSWER KEY

1 4 . Consider the following statements :

(A) Monosaccharides are optically active polyhydroxy carbonyl compounds.

(B) Fructose does not reduce Fehling's solution because it is a ketose.

(C) -D(+)Glucose and -D(+)-glucose are anomers.

(D) D-Glucose and D-mannose are C-2 epimers.

1 5 . Consider the following statements about sucrose.

(A) Hydrolysis of surcose with dilute acid yields an equimolar mixture of D-gluvose and D-fructose

(B) Acid h

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