Biochemistry MCQ Quiz Hub

1. PCR can be used to amplify a specific fragment of DNA from which of the following?"
A drop of blood
A hair follicle
A fragment of skin
All of these

2. Transformation means
formation of a pilus
acquiring DNA from the bacterial cell environment
plasmid containing a F factor
F+ and F- strains of bacteria

3. Restriction maps
allows comparison between DNA molecules without the need to determine nucleotide sequence
allows comparison between DNA molecules but requires to determine nucleotide sequence
does not allow comparison between DNA molecules
none of the above

4. Which of the following is correct?
HIV is a retrovirus that kills human helper T cells
Causes acquired immune deficiency syndrome (AIDS)
Cripples the immunity systems
All of the above

5. A PCR cycle consists of
three steps, denaturation, primer annealing and elongation
three steps, denaturation, initiation and elongation
three steps, primer annealing, elongation and termination
three steps, initiation, elongation and termination

6. How many ds DNA molecule can be produced, which comprise precisely the target region in double strand form during 4th cycle of PCR?
Two ds DNA molecule
Three ds DNA molecule
Eight ds DNA molecule
Four ds DNA molecule

7. PCR can be used in
cloning
sequencing
medical diagnosis and forensic medicine
all of the above

8. PCR (Polymerase Chain Reaction) can make multiple copies of
DNA
RNA
protein
carbohydrate

9. PCR is an abbreviation for
Protein Change Reaction
Polymerase Chain Reaction
Positive Charge Reaction:
Preliminary Change Rate

10. PCR amplifies millions of copies of
a short fragment of DNA
the entire genome (all the DNA in a sample)
both (a) and (b)
short chain RNA

11. Southern blotting involves
electrophoresis of DNA molecules and then blotting the separated DNA bands followed by incubation
electrophoresis of DNA molecules and then blotting the separated RNA bands followed by incubation
electrophoresis of DNA molecules followed by incubation
electrophoresis of RNA molecules and then blotting the separated RNA bands followed by incubation

12. Bactriophages absorb to a bacterial surface and inject the phage DNA through the
cell wall into cytosol
cell wall into plasmamembrane
both (a) and (b)
cell wall into endoplasmic reticulum

13. In a PCR reaction after four cycles, each molecule of a duplex DNA will give rise to
16 single strands of DNA
16 double stranded DNA
18 single strands of DNA
18 double stranded DNA

14. Additional mono saccharides are added in Golgi to produce
either high mannose type oligosaccharide or a complex type
either fructose type monosaccharide or a complex type
either high sucrose type polysaccharide or a complex type
none of the above

15. The PCR, polymerase chain reaction is becoming the method of choice for
Alteration of gene
screening gene
sterilization of gene
all of these

16. Northern blotting is
widely different than southern blotting
another name for southern blotting
analogous to southern blotting
none of the above

17. What technique can be used to determine the murderer who left blood with the victim?
DNA sequencing
PCR amplification
Western blot
RFLP mapping

18. DNA fragments in a restriction digest can be separated by electrophoresis in
poly acrylamide
agarose gel
both (a) and (b)
none of these

19. Glycolytic pathway regulation involves
allosteric stimulation by ADP
allosteric inhibition by ATP
feedback, or product, inhibition by ATP
all of the above

20. During catabolism, only about 40% of the energy available from oxidizing glucose is used to synthesize ATP. Remaining 60%
is lost as heat
is used to reduce NADP
remains in the products of metabolism
is stored as fat.

21. Why does the glycolytic pathway continue in the direction of glucose catabolism?
There are essentially three irreversible reactions that act as the driving force for the pathway
High levels of ATP keep the pathway going in a forward direction
The enzymes of glycolysis only function in one direction
Glycolysis occurs in either direction

22. The released energy obtained by oxidation of glucose is stored as
a concentration gradient across a membrane
ADP
ATP
NAD+

23. A kinase is an enzyme that
removes phosphate groups of substrates
uses ATP to add a phosphate group to the substrate
uses NADH to change the oxidation state of the substrate
removes water from a double bond

24. During catabolism, only about 40% of the energy available from oxidizing glucose is used to synthesize ATP. Remaining 60%
is lost as heat
is used to reduce NADP
remains in the products of metabolism
is stored as fat.

25. Why does the glycolytic pathway continue in the direction of glucose catabolism?
There are essentially three irreversible reactions that act as the driving force for the pathway
High levels of ATP keep the pathway going in a forward direction
The enzymes of glycolysis only function in one direction
Glycolysis occurs in either direction

26. For every one molecule of sugar glucose which is oxidized __________ molecule of pyruvic acid are produced.
1
2
3
4

27. In the glycogen synthase reaction, the precursor to glycogen is
glucose-6-P
UTP-glucose
UDP-glucose
glucose-1-P

28. The active form of glycogen phosphorylase is phosphorylated, while the dephosphorylation of which active form occurs?
Glycogen synthase
Glycogen semisynthase
Glycogen hydrolase
Glycogen dehydrogenase

29. The amount of energy received from one ATP is
76 kcal
7.3 kcal
760 kcal
1000 kcal

30. The enzymes of glycolysis in a eukaryotic cell are located in the
intermembrane space
plasma membrane
cytosol
mitochondrial matrix

31. When concentration of the reactants is higher than the equilibrium concentration then
the gibbs free energy will be positive
the gibbs free energy will be negative
more products will be formed
Both (b) and (c)

32. Which of the following is not true of glycolysis?
ADP is phosphorylated to ATP via substrate level phosphorylation
The pathway does not require oxygen
The pathway oxidizes two moles of NADH to NAD+ for each mole of glucose that enters
The pathway requires two moles of ATP to get started catabo-lizing each mole of glucose

33. In glycolysis, ATP is formed by the transfer of a high-energy phosphate from 1,3-bisphosphoglycerate to ADR No such high-energy phosphate donor has ever been isolated in mitochondria because
the techniques for isolating the phosphate donor are not refined enough
no such phosphate donor exists
the high-energy phosphate donor is very short-lived and difficult to isolate
None of the above

34. ATP is from which general category of molecules?
Polysaccharides
Proteins
Nucleotides
Amino acids

35. The glycolytic pathway (glucose → 2 pyruvate) is found
in all living organisms
primarily in animals excluding particles
only in eukaryotes
only in yeast

36. Which of the following could act as an uncoupler of electron transport and ATP synthesis?
The Fo base-piece of ATP synthase (without the Fl subunit)
Dinitrophenol
neither (a) nor (b)
Both (a) and (b)

37. Which of the following is not a mechanism for altering the flux of metabolites through the rate-determining step of a pathway?
Allosteric control of the enzyme activity
Diffusional coupling between adjacent active sites
Genetic control of the enzyme concentration
Covalent modification of the enzyme

38. Phosphofructokinase, the major flux-controlling enzyme of glycolysis is allosterically inhibited and activated respectively by
ATP and PEP
AMP and Pi
ATP and ADP
Citrate and ATP

39. Which of the following regulates glycolysis steps?
Phosphofructokinase
Hexose kinase
Pyruvate kinase
All of these

40. During glycolysis, the major energy generating step involves
pyruvate kinase
phosphoglycerate kinase
glyceraldehyde-3 -dehydrogenase
Phosphofructokinase

41. Fructose-2,6-bisphosphate
activates fructose-1,6-bisphosphatase
activates phosphofructokinase
inhibits fructose-1,6-bisphosphatase
both (b) and ©

42. Glucose from the breakdown of glycogen is obtained in
the liver by phosphorolysis
the muscles by phosphorolysis
the muscles by hydrolysis
both (a) and (b)

43. Glycogen has
α-1,4 linkag
α-1,6 linkages
α-1,4 and α-1,6 linkages
α-1,4 and β-1,6 linkage

44. Membrane potential and the proton gradient
are both required to make ATP
are sufficient, separately, to make ATP from ADP + Pi;
reinforce one another when respiratory inhibitors are present
cancel one another when uncouplers are present

45. The irreversibility of the thiokinase reactions (formation of initial acyl-CoA)
make this activation reaction the committed step on the pathway
is due to the subsequent hydrolysis of the product
applies only to even-chain fatty acids
both (a) and (b)

46. Long-chain fatty acids are oxidized step-wise in one carbon units starting from the
carboxyl end
aliphatic end
both (a) and (b)
none of these

47. How many molecules of acetyl-CoA are produced in oxidation of palmitic acid (C16), which involves seven rounds of oxidation?
6
7
8
9

48. he oxidation of methanol (wood alcohol) in human retina tissue leads directly to the formation of
formaldehyde
sugars
CO2
none of these

49. The maximum energy per gram on oxidization is yielded from
fat
protein
glycogen
starch

50. The oxidation of methanol (wood alcohol) in human retina tissue indirectly leads to
pressure builds up
colour blindness
blindness
all of these

51. Each cycle of β-oxidation produces
1 FADH2, 1 NAD+, and 1 acetyl-CoA
1 FADH2, 1 NADH and 1 acetyl-CoA
1 FADH2, 1 NADH and 2 CO2 molecules
1 FAD, 1 NAD+ and 2 CO2 molecules

52. The three identical b subunits of the F1, complex during ATP synthesis have
different affinities for ATP but not for ADP
different affinities for ADP but not for ATP
different affinities for ATP and for ADP
similar affinities for ADP and ATP

53. Where the acyl-CoA formed in the cytosol is transported for oxidation?
Mitochondrial matrix
Microsomes
Endoplasmic reticulum
Remains in cytosol

54. The transport of acyl-CoA for oxidation using a shuttle involves formation of the intermediate
3 acetyl-CoA
Acyl-coenzyme A
acyl-carnitine
None of these

55. FAD is reduced to FADH2 during
electron transport phosphorylation
lactate fermentation
Krebs cycle
glycolysis

56. During glycolysis, electrons removed from glucose are passed to
FAD
NAD+
acetyl CoA
pyruvic acid

57. A biological redox reaction always involves
an oxidizing agent
a gain of electrons
a reducing agent
all of these

58. Coenzyme Q is involved in electron transport as
directly to O2
a water-soluble electron donor
covalently attached cytochrome cofactor
a lipid-soluble electron carrier

59. The carbon dioxide is primary a product of
Krebs cycle
glycolysis
electron transport phosphorylation.
lactate fermentation.

60. Which of the following is not a feature of oxidative phosphorylation?
Direct transfer of phosphate from a substrate molecule to ADP
An electrochemical gradient across the inner mitochondrial membrane
A membrane bound ATP synthase
A protonmotive force