🧪 Biotechnology MCQ Quiz Hub

1. What are the effects of increasing concentration of reaction components?
It increases chances of ligation in both intramolecular and intermolecular reactions
It increases chances of ligation only in intermolecular and no effect on intramolecular
It decreases chances of ligation in intramolecular and increases in that of intermolecular
It decreases chances of ligation in both types of reaction

2. Enzyme commonly used for carrying out ligation reaction is ____________
Transferase
Reverse transciptase
Ligase
DNase

3. Which of the following statements is correct with respect to T4 DNA ligase?
It can carry out only blunt ended ligations
It doesn’t requires ATP
It requires a phosphate group at 3’ end and a hydroxyl group at 5’ end for the molecule to be joined
It is obtained from T4 bacteriophage upon infection by E. coli

4. If blunt ended ligations are to be carried out. Which of the following enzymes can be used?
E. coli DNA ligase
T4 DNA ligase
Both of these enzymes act equally in carrying out blunt ended ligations
None of them is able to carry out blunt ended ligations

5. Mechanism of ligation for both T4 DNA ligase and E. coli DNA ligase makes use of Adenosine Monophosphate (AMP). Which of the steps is involved in the ligation mechanism?
AMP is added to the 5’ phosphate of one of the DNA molecule
It leads to the liberation of pyrophosphate from NAD and nicotinamide mononucleotide from ATP
The AMP is further displaced by an electrophilic attack
The AMP is further displaced by nucleophilic attack by 3’ hydroxyl of the same DNA molecule

6. Topoisomerase is also an enzyme which is used for carrying out ligation. The correct statement for topoisomerase is?
They act only on double stranded molecules
They alter the degree of supercoiling of DNA molecules
They are less effective than conventional DNA ligase
There are three types of topoisomerases

7. Phage based recombination systems are used for ____________
cleaving the molecules at specific sites
adding the molecules at specific sites
breakage and rejoining the molecules at specific sites
breakage at random sites

8. Bacteriophage lambda is having a phage recombination system. Following are the characteristics of this system ____________
It is used for inserting phage genome into the bacterium
It is used for inserting bacterial genome into the phage
The specific site in bacteria is attB and that in phage is attP
The specific sites in both of them are called as attP

9. Ligation enzymes are used for ligating newly synthesized okazaki fragments. What holds true for okazaki fragments?
Okazaki fragments are short fragments of DNA formed on the leading strand
Okazaki fragments are large fragments of DNA formed on the lagging strand
Okazaki fragments are short fragments of DNA formed on the lagging strand
Okazaki fragments are large fragments of DNA formed on the leading strand

10. Introduction of DNA molecules into the recipient organism is termed as ____________
transformation
translation
transduction
transcription

11. Many bacterial species are having a natural ability to take up the exogenous DNA material. Which of the statement is not correct in regard to it?
This ability is termed as competence
It is not limited to particular growth phases
The bacteria may develop new biochemical abilities under special conditions such as nutrient deprivation
Induction of specific set of bacterial proteins may take place

12. Which of the statements hold true for conjugation?
Conjugation is the natural process of transferring DNA from one species to another
It is the artificial process in case the cells are not able to take them up naturally
The plasmids are transferred from one cell to another by physical contact
The plasmids are transferred from one cell to another by chemical means

13. F plasmid is often used in conjugation. The correct statement is?
The F plasmid encodes the factor which is transferred from one cell to another
The factor encoded by the F plasmid is called as Filamentous (F) factor
It is transferred from one cell to another by filament
The bacteria must belong to same species to carry out the conjugation

14. Plasmids can be classified into how many types depending on the genes present for their transformation?
1
2
3
4

15. Chemical transformation refers to the methods which use chemicals in order to carry out transformation. Which of the following statements is true with respect to it?
Chemical transformation decreases the efficiency of transformation as compared to natural transformation
Ice cold calcium solution followed by heat shock is responsible for affecting the efficiency of DNA uptake
The mechanism responsible for it named as ‘the heat shock model’
Other complex mixtures such as those containing Manganese and hexamine cobalt can’t be used to affect the efficiency

16. Electroporation is also used for taking up the DNA by the cells. It constitutes of ____________
inserting the DNA into the cells via an electric shock
increased efficiency than both natural and chemical methods
causing the least amount of damage in comparison to other methods
decreased efficiency than both natural and chemical methods

17. Transformation carried out using a particle gun is known as biolistic transformation. It falls under which category of transformation?
Physical
Chemical
Electroporation
Natural

18. The particle gun method consists of which of the following steps?
The DNA of interest is absorbed onto microprojectile beads
These beads are often made of aluminium
The explosion in a gun propels a macroprojectile forward which in turn propels microprojectile beads
The macroprojectiles and microprojectiles both cross the perforated plate and hit the target tissue behind it

19. Isolation of genomic DNA follows the same principles as that of obtaining plasmid from E. coli. Which of the following is not included in it?
Cell lysis
Removal of proteins
Removal of chromosomal DNA
Dissolving plasmid in water

20. How many methods are there for obtaining the plasmid DNA from the bacteria?
1
2
3
4

21. Cell lysis is carried out by which substance?
Lysozyme and detergents
Water
Sugar solution
Suphuric Acid

22. Chromosomal or genomic DNA is separated by ____________
Sedimentation
Dissolution in water
Centrifugation
Distillation

23. Proteins can be removed via treatment by?
Phenol and chloroform treatment
Treatment with sodium hydroxide
Chloroform treatment alone
Centrifuging

24. Nucleic acid precipitated constitutes of ____________
plasmid DNA
plasmid DNA, along with RNA and chromosomal DNA
rna alone
chromosomal DNA only

25. Treatment with exonuclease leads to removal of ____________
remnants of chromosomal DNA
RNase
plasmid DNA which is circularized
proteins

26. Adsorption onto a solid phase support followed by elution is used as an alternative for separation of which component?
chromosomal DNA
plasmid DNA
RNA alone
other impurities

27. Which of the following components bind to the solid column made of silica, under high salt concentration?
Proteins
Polysaccharides
Both proteins and polysaccharides
Plasmid DNA

28. Purification of DNA by using silica derivatized groups by DEAE is termed as ____________
ion exchange resin based method.
silica based purification
atom based resin exchange method
packed bed purification

29. Which of the following is correct with respect to caesium chloride centrifugation?
Caesium is light in weight
The dissolution of caesium and nucleic acids leads to the formation of gradients
According to the amount of supercoiling and A+T content, the DNA settles
Nicked DNA settles below than supercoiled DNA

30. Which of the following components settles at the bottom?
RNA
Proteins
Nicked DNA
Supercoiled DNA

31. The location of plasmid DNA can be visualized by addition of:
bromophenol blue
ethidium bromide
ortho xylene
texas red

32. Sand does not show any bulking when:
Completely saturated
Partially saturated
Contains small amount of impurities
Voids are partially filled with air

33. What effect does bulking have on fresh concrete?
Strength reduces
Shrinkage increases
Volume reduces
Workability increases

34. Why is natural cement used very limitedly?
Brown in Colour
Standard consistency is not met with
Sets too quickly
Particle size is too fine

35. Who invented Portland cement and in which year?
William Aspdin, 1824
William Aspdin, 1840s
Joseph Aspdin, 1840s
Joseph Aspdin, 1824

36. What is the average particle size of cement?
15 microns
45 microns
75 microns
100 microns

37. What is the meaning of soundness of cement?
Ability to flow when mixed
Ability to make ringing noise when struck
Ability to form strong and sound structure
Ability to retain volume after setting.

38. Time elapsed from the instance of adding water until paste ceases to behave as fluid is called:
Initial setting time
Final setting time
Intermediate setting time
Absolute setting time

39. Which of the below mentioned is not a result of field test performed on cement?
There should not be any lumps
It should feel cold when you put your hand in bag of cement
The colour should be blackish grey
It should not be gritty when rubbed with finger

40. Which equipment is used to test the setting time of cement?
Core cutter
Vibrator
Universal testing machine (UTM)
Vicat apparatus

41. What is the initial setting time of cement?
1 hour
30 minutes
15 minutes
30 hours

42. Use of coarser cement particles leads to:
Low durability
Higher strength
Low consistency
Higher soundness

43. Green cement is:
Green coloured cement
Cement mixed with plant products
Cement mixed with recycled materials
Cement mixed with green algae

44. What is the depth the needle in Vicat apparatus should penetrate into the cement paste in consistency test?
33-35 cm from bottom of the mould
33-35 mm from top of the mould
33-35 cm from top of the mould
33-35 mm from bottom of the mould

45. What is the most dominant constituent of cement?
Silica
Lime
Magnesia
Alumina

46. Deficiency of lime in cement leads to:
Unsound cement
Disintegration of cement
Quick setting of cement
Expansion of cement

47. What effect does calcium sulphate have on cement?
Retards setting action
Acts as flux
Imparts colour
Reduces strength

48. Which of the following adds a quick-setting property to cement?
Magnesium oxide
Silicon dioxide
Iron oxide
Aluminium oxide

49. Which of the following imparts greenish grey colour to cement?
Calcium silicate
Calcium aluminate
Calcium aluminate ferrite
Calcium carbonate

50. Excess of Alkali in cement results in:
Dry cement paste
Efflorescence
Less plasticity
Unsound cement