Carbohydrate MCQs

By: Prof. Dr. Fazal Rehman | Last updated: May 22, 2025

1. : What are the constituents of the structure of ‘Agar’, the common culture medium for microbes in the laboratory?
(A) D-Glucose derivative and L-Galactose
(B) D-Mannose derivative and D-Galactose
(C) D-Galactose and an L-Galactose derivative
(D) An L-Mannose derivative and D-Galactose

2. : Treatment of sucrose with conc. HNO₃ provides which of the following?
(A) Oxalic acid
(B) Glucose + Fructose
(C) Nitrosucrose
(D) Laevulinic acid

3. : Glucose and fructose react with which reagent to give similar product?
(A) Tollen’s reagent
(B) Hydroxyl amine
(C) Phenyl hydrazine
(D) All of these

4. : Epimers are compounds that vary in
(A) Functional group
(B) Configuration at any carbon
(C) Ring size
(D) Configuration at α-carbon

5. : Method used to ascent the series of aldoses is called
(A) Weerman’s reaction
(B) Ruff’s method
(C) Kilian synthesis
(D) Wohl’s synthesis

6. : Mutarotation is exhibited by
(A) All carbohydrates
(B) All disaccharides
(C) All polysaccharides
(D) All monosaccharides

7. : In ______ a freshly prepared solution of glucose has a specific rotation of +110° but on keeping for some time it changes to +52.7°.
(A) Mutarotation
(B) Alternation
(C) Epimerization
(D) None of these

8. : Though fructose is laevorotatory yet its name is written as D-fructose. This ‘D’ prefix indicates which of the following?
(A) Specific rotation
(B) Generic relationship with D-glyceraldehydes
(C) Generic relationship with D-glucose
(D) Mutarotation

9. : Configuration of carbohydrates relative to glyceraldehydes was suggested by which of the following?
(A) Rosanoff
(B) Hirst
(C) Howarth
(D) Fischer

10. : A specific diagnostic test for carbohydrates is
(A) Molisch’s test
(B) Tollen’s test
(C) Fehling’s test
(D) Osazone formation

11. : Glucose and mannose may be obtained by Kiliani synthesis from which of the following?
(A) D-ribose
(B) D-xylose
(C) D-arabinose
(D) D-lyxose

12. : Acetylation of fructose yields a
(A) Pentacetyl derivative
(B) Diacetyl derivative
(C) Tetraethyl derivative
(D) Monodactyl derivative

13. : Although glucose has an aldehydic group it does not restore pink colour of Schiff’s reagent. It is because
(A) There is steric hindrance
(B) -I effect of hydroxyl groups
(C) Aldehydic group is involved in hemiacetal formation
(D) There is no aldehydic group in glucose

14. : In _______ Isomers differ in configuration at the asymmetric carbon produced due to hemiacetal ring formation in carbohydrates.
(A) Epimers
(B) Anomers
(C) Conformers
(D) Tautomers

15. : The ring structure of glucose does not explain _______.
(A) Stereochemistry of glucose
(B) Mutarotation phenomenon
(C) Existence of two forms of glucose
(D) No reaction with Schiff’s reagent

16. : Hydrolysis of methyl glucoside tetramethyl-D followed by oxidation provides which of the following?
(A) Arabinotrimethoxy glutaric acid
(B) Ribotrimethoxy glutaric acid
(C) Xylotrimethoxy glutaric acid
(D) Dimethoxy succinic acid

17. : Which of the polysaccharide on hydrolysis provides only fructose?
(A) Cellulose
(B) Amylopectin
(C) Inulin
(D) Amylose

18. : Which of the following is the test that may be used to distinguish between glucose and fructose?
(A) Schiff’s reagent test
(B) Selivenoff’s test
(C) Tollen’s reagent test
(D) Fehling’s solution test

19. : Which is not a method for determining ring size in carbohydrates?
(A) Haworth and Hirst method
(B) Lactone formation method
(C) Molisch method
(D) Periodic acid oxidation method

20. : Nucleoside adenosine on hydrolysis gives which of the following?
(A) Purine base + Deoxyribose
(B) Purine base + Ribose
(C) Pyrimidine base + Ribose
(D) Pyrimidine base + Deoxyribose

21. : Carbohydrates are characterized by the presence of which of the following?
(A) Asymmetric carbon
(B) Carbonyl group
(C) Hydroxyl group
(D) All of these

22. : Which is not a polysaccharide?
(A) Insulin
(B) Cellulose
(C) Cellobiose
(D) Amylase

23. : Which interaction is not a stabilizing factor in the 3-D structure of polysaccharides?
(A) Hydrophobic interactions
(B) Disulphide bonds
(C) Hydrogen bonding
(D) Electrostatic interactions

24. : Which is an epimer of glucose?
(A) Fructose
(B) Ribose
(C) Galactose
(D) Maltose

25. : Which is true regarding open chain structure of glucose?
(A) There are four asymmetric carbons
(B) There are five asymmetric carbons
(C) There are six asymmetric carbons
(D) There are three asymmetric carbons

26. : Which disaccharide contains α-1→1-glycosidic linkage?
(A) Sucrose
(B) Lactose
(C) Trehalose
(D) Maltose

27. : Honey is rich in the hydrolytic product of which of the following?
(A) Inulin
(B) Maltose
(C) Lactose
(D) Starch

28. : Which of the following is a polymeric unit of starch which has branched structure?
(A) Chitin
(B) Amylose
(C) Glycogen
(D) Amylopectin

29. : Which disaccharide is not a plant product?
(A) Maltose
(B) Lactose
(C) Sucrose
(D) None

30. : Which is true about the structure of cellulose?
(A) The main backbone of α-1→4-linkages and branches with β-1→6-linkages
(B) The main backbone of β-1→4-linkages and no branches
(C) The main backbone of β-1→6-linkages and branches with β-1→4-linkages
(D) The main backbone of α-1→4-linkages and no branches

31. : What is the general formula for polysaccharides?
(A) (CH₂O)n
(B) (CH₁₂O)n
(C) (C&H₁Os)n
(D) (C₆H₁₀O₆)n

32. : Which is the distinguishing test between monosaccharides and disaccharides?
(A) Barfoed’s Test
(B) Bial’s Test
(C) Seliwanoff’s Test
(D) Hydrolysis Test

33. : The copper in Barfoed’s Solution is not reduced by which of the following?
(A) Glucose
(B) Sucrose
(C) Mannose
(D) Ribose

34. : Iodine solution provides no colour with which of the following?
(A) Glycogen
(B) Starch
(C) Dextrin
(D) Cellulose

35. : Which is not a polymer of D-Glucose?
(A) Inulin
(B) Amylose
(C) Starch
(D) Glycogen

36. : What is the reason for the selection of furanose (ribose) rather than pyranose (glucose) for nucleic acids?
(A) Furanose ring is more stable than pyranose
(B) Furanose ring is more flexible than pyranose
(C) It is sterically difficult to incorporate a pyranose ring in the double helix
(D) Furanose phosphodiesters are easier to form

37. : Which has been isolated from human heart muscles?
(A) D-Arabinose
(B) D-Ribose
(C) D-Lyxose
(D) D-Xylose

38. : Benedict’s test is likely to give weakly positive results with concentrated urine due to the action of
(A) Uric acid
(B) Ammonium salts
(C) Urea
(D) Phosphates

39. : Dextran is a polymer of glucose units. What type of linkages is predominant in its structure?
(A) α-1,6-glycosidic linkages
(B) β-1,4-glycosidic linkages
(C) α-1,2 and β-1,3 glycosidic linkages
(D) All of these

40. : Which carbohydrate makes the terminal residue in ‘O’ substance (H-antigen) – the mother antigen of ‘ABO’ blood group substances?
(A) N-AcGlu
(B) Fucose
(C) Gal
(D) Xylose

41. : Chitin that forms the exoskeleton of crustaceans consists of:
(A) β-1,4-linkages between glucose residues
(B) α-1,4-linkages between N-acetyl-glucosamine residues
(C) β-1,4-linkages between N-acetyl-glucosamine and glucose residues
(D) β-1,4-linkages between N-acetyl-glucosamine residues

42. : Which is considered as the most abundant organic compound in the biosphere?
(A) Starch
(B) Chitin
(C) Hyaluronidase
(D) Cellulose

43. : Which carbohydrate is polymerized through β-1,4 glycosidic linkages?
(A) Amylose
(B) Lactose
(C) Sucrose
(D) Maltose

44. : β-Amylase of malt hydrolyzes starch by:
(A) Hydrolyzing the internal glycosidic linkages
(B) Removing glucose molecules from the reducing end
(C) Removing maltose units from the non-reducing end
(D) Hydrolyzing glycosidic linkages

45. : Phosphorylation of carbohydrates makes the molecule anionic. What could be the purpose of this ionization?
(A) The negative charge results in better interaction with enzyme active sites
(B) It prevents sugars from leaking out of the plasma membranes
(C) It creates reactive intermediates for glycosidic linkage formation
(D) All of these

46. : What is the systematic name of sucrose?
(A) 1-α-D-glucopyranosyl-2-β-D-fructofuranoside
(B) 1-α-D-glucopyranosyl-2-β-D-fructopyranoside
(C) 1-β-D-glucofuranosyl-2-α-D-fructopyranoside
(D) 1-β-D-glucofuranosyl-2-α-D-fructofuranoside

47. : Which oligosaccharide mediates the binding of H. pylori to the gastric mucosa?
(A) Oligosaccharide from Blood Group ‘O’ substance
(B) Oligosaccharide from Blood Group ‘A’ substance
(C) Oligosaccharide from Blood Group ‘B’ substance
(D) Oligosaccharide of ganglioside GM1

48. : In patients with uncontrolled diabetes mellitus, which metabolic change is true?
(A) Impaired uptake of glucose
(B) Increased rate of fatty acid oxidation
(C) Impaired synthesis of fatty acids
(D) All of these

49. : During the synthesis of sucrose, glucose is activated to which moiety?
(A) UDP-Glucose
(B) Glucose-1-Phosphate
(C) Phospho-glucosyl-1-phospho-pyrophosphate
(D) Glucose-6-Phosphate

50. : In the presence of dilute alkali, monosaccharides undergo reversible isomerisation. What is the name of this reaction?
(A) Kiliani reaction
(B) Weermann rearrangement
(C) Lobry de Bruyn van Ekenstein rearrangement
(D) Mutarotation