FREE BIOCHEMISTRY MCQs WITH ANSWER

FREE BIOCHEMISTRY MCQs WITH ANSWER

      1.  All proteins contain the
      (A) Same 20 amino acids 
      (B) Different amino acids
      (C) 300 Amino acids occurring in nature
      (D) Only a few amino acids

     2. Proteins contain
      (A) Only L- α - amino acids
      (B) Only D-amino acids
      (C) DL-Amino acids
      (D) Both (A) and (B)

     3. The optically inactive amino acid is
      (A) Glycine 
      (B) Serine
      (C) Threonine
      (D) Valine

     4. At neutral pH, a mixture of amino acids in solution would be predominantly:
         (A) Dipolar ions
         (B) Nonpolar molecules
         (C) Positive and monovalent
         (D) Hydrophobic

    5. The true statement about solutions of amino acids at physiological pH is
       (A) All amino acids contain both positive and negative charges
       (B) All amino acids contain positively charged side chains
       (C) Some amino acids contain only positive charge
       (D) All amino acids contain negatively charged side chains

    6. pH (isoelectric pH) of alanine is
       (A) 6.02
       (B) 6.6
       (C) 6.8
       (D) 7.2

   7. Since the pK values for aspartic acid are 2.0, 3.9 and 10.0, it follows that the isoelectric (pH) is
      (A) 3.0
      (B) 3.9
      (C) 5.9
      (D) 6.0

     8. Sulphur containing amino acid is
       (A) Methionine
       (B) Leucine
       (C) Valine
       (D) Asparagine

    9. An example of sulphur containing amino acid is
        (A) 2-Amino-3-mercaptopropanoic acid 
        (B) 2-Amino-3-methylbutanoic acid 
        (C) 2-Amino-3-hydroxypropanoic acid
        (D) Amino acetic acid

    10. All the following are sulphur containing amino acids found in proteins except 
      (A) Cysteine 
      (B) Cystine 
      (C) Methionine
      (D) Threonine 

     11. An aromatic amino acid is
         (A) Lysine 
         (B) Tyrosine 
         (C) Taurine 
         (D) Arginine

12. The functions of plasma albumin are
(A) Osmosis
(B) Transport
(C) Immunity
(D) both (A )and (B)

 13. Amino acid with side chain containing basic groups is
(A) 2-Amino 5-guanidovaleric acid
(B) 2-Pyrrolidine carboxylic acid
(C) 2-Amino 3-mercaptopropanoic acid
(D) 2-Amino propanoic acid

 14. An example of α-amino acid not present in proteins but essential in mammalian metabolism is (A) 3-Amino 3-hydroxypropanoic acid
(B) 2-Amino 3-hydroxybutanoic acid
(C) 2-Amino 4-mercaptobutanoic acid
(D) 2-Amino 3-mercaptopropanoic acid

15. An essential amino acid in man is
(A) Aspartate
(B) Tyrosine
(C) Methionine
(D) Serine

 16. Non essential amino acids
(A) Are not components of tissue proteins
(B) May be synthesized in the body from essential amino acids
(C) Have no role in the metabolism
(D) May be synthesized in the body in diseased states

 17. Which one of the following is semiessential amino acid for humans?
(A) Valine
(B) Arginine
(C) Lysine
(D) Tyrosine

18. An example of polar amino acid is
(A) Alanine
(B) Leucine
(C) Arginine
(D) Valine

19. The amino acid with a nonpolar side chain is
(A) Serine
(B) Valine
(C) Asparagine
(D) Threonine

20. A ketogenic amino acid is
(A) Valine
(B) Cysteine
(C) Leucine
(D) Threonine

21. An amino acid that does not form an α- helix is
(A) Valine
(B) Proline
(C) Tyrosine
(D) Tryptophan

22. An amino acid not found in proteins is
(A) β-Alanine
(B) Proline
(C) Lysine
(D) Histidine

23. In mammalian tissues serine can be a biosynthetic precursor of
(A) Methionine
(B) Glycine
(C) Tryptophan
(D) Phenylalanine

24. The conversion of pyruvate to acetyl CoA and CO2
(A) Is reversible
(B) Involves the participation of lipoic acid
(C) Depends on the coenzyme biotin
(D) Occurs in the cytosol

25. Pasteur effect is
(A) Inhibition of glycolysis
(B) Oxygen is involved
(C) Inhibition of enzyme phosphofructokinase
(D) All of these

26. How many ATPs are produced in the conversion of phosphoenol pyruvate to citrate?
(A) 1
(B) 2
(C) 4
(D) 6

27. Reduced glutathione functions in R.B.Cs to
(A) Produce NADPH
(B) Reduce methemoglobin to hemoglobin
(C) Produce NADH
(D) Reduce oxidizing agents such as H2O2

 28. Phenylalanine is the precursor of
(A) L-DOPA
(B) Histamine
(C) Tyrosine
(D) Throxine

29. D-Mannose is present in some plant products like
(A) Resins
(B) Pectins
(C) Mucilage
(D) Gums

30. Galactose is a main constituent of
(A) Milk sugar
(B) Honey
(C) Cane sugar
(D) Chitin

 31. Glucosamine is an important constituent of
(A) Homopolysaccharide
(B) Heteropolysaccharide
(C) Mucopolysaccharide
(D) Dextran

32. Glycogen is present in all body tissues except
(A) Liver
(B) Brain
(C) Kidney
(D) Stomach

33. Iodine test is positive for starch, dextrin and
(A) Mucoproteins
(B) Agar
(C) Glycogen
(D) Cellulose

34. The general formula for polysaccharide is
(A) (C6H10O5)n
(B) (C6H12C6)n
(C) (C6H12O5)n
(D) (C5H10O5)n

35. Epimers of glucose is
(A) Fructose
(B) Galactose
(C) Ribose
(D) Deoxyribose

36. Human heart muscle contains
(A) D-Arabinose
(B) D-Ribose
(C) D-Xylose
(D) L-Xylose

37. The intermediate n hexose monophosphate shunt is
(A) D-Ribulose
(B) D-Arabinose
(C) D-xylose (D)
D-Lyxose

38. On boiling Benedict’s solution is not reduced by
(A) Sucrose
(B) Lactose
(C) Maltose
(D) Fructose

39. The distinguishing test between monosaccharides and dissaccharide is
(A) Bial’s test
(B) Seliwanoff’s test
(C) Barfoed’s test
(D) Hydrolysis test

40. Barfoed’s solution is not reduced by
(A) Glucose
(B) Mannose
(C) Sucrose
(D) Ribose

41. Cori cycle is
(A) Synthesis of glucose
(B) reuse of glucose
(C) uptake of glycose
(D) Both (A) & (B)

42. Cane sugar is known as
(A) Galactose
(B) Sucrose
(C) Fructose
(D) Maltose

43. Which of the following is not reducing sugar?
(A) Lactose
(B) Maltose
(C) Sucrose
(D) Fructose

44. α−D-Glucose and β−D-glucose are related by
 (A) Epimers
 (B) Anomers
 (C) Multirotation
 (D) Ketoenol pair

 45. The stable ring formation in D-Glucose involves
(A) C-1 and C-4
(B) C-1 and C-2
(C) C-1 and C-5
(D) C-2 and C-5

 46. Reduction of Glucose with Ca++ in water produces
(A) Sorbitol
(B) Dulcitol
(C) Mannitol
(D) Glucuronic acid

47. Starch and glycogen are polymers of
(A) Fructose
(B) Mannose
(C) α−D-Glucose
(D) Galactose

48. Reducing ability of carbohydrates is due to
(A) Carboxyl group
(B) Hydroxyl group
(C) Enediol formation
(D) Ring structure

49. Which of the following is not a polymer of glucose?
(A) Amylose
(B) Inulin
(C) Cellulose
(D) Dextrin

50. Invert sugar is
(A) Lactose
(B) Mannose
(C) Fructose
(D) Hydrolytic product of sucrose

51 The carbohydrate reserved in human body is
(A) Starch
(B) Glucose
(C) Glycogen
(D) Inulin

52 A dissaccharide linked by α-1-4 Glycosideic linkages is
(A) Lactose
(B) Sucrose
(C) Cellulose
(D) Maltose