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Biochemisty Main > 7th-Biochemistry-Exam-DNA-and-RNA-Metabolism-Batch-2026 > Flashcards

7th-Biochemistry-Exam-DNA-and-RNA-Metabolism-Batch-2026 Flashcards

1
Q

Which ganglioside serves as the receptor for cholera toxin in the intestinal cells?
A. GM2
B. GM1
C. GM3
D. GM4

A

B. GM1

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2
Q

The enzyme that is deficient in Niemann Pick’s disease?
A.glucocerebrosidase
B.hexosaminidase A
C. sphingomyelinase
D. §-gaIactocerebrosidase

A

C. sphingomyelinase

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3
Q

Among the following special lipids, which utilizes sphingosine for it synthesis?
A.cardiolipin
B.plasmalogen
C.lecithin
D.sphingomyelin

A

D.sphingomyelin

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4
Q

Which of the following phospholipids acts as a lipotropic agent?
A. phosphatidyl choline
B.phosphatidyl inositol
C.phosphatidyl serine
D.cardiolipin

A

A. phosphatidyl choline

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5
Q

Degradation of a galactocerebroside generates which components?
A.sphingosine + fatty acid + galactose
B.glycerol + fatt:y acids + phosphoric acid + galactose
C.glycerol + fatt:y acids + phosphoric acid + nitrogenous base + galactose
D.sphingosine + fatty acid + phosphoric acid + galactose

A

A.sphingosine + fatty acid + galactose

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6
Q

What is the major component of the lung surfactant?
A.dipalmitoyl lecithin
B.dipalmitoylphosphatidyl serine
C.dipalmtoylcephalin
D.dipalmitoylphosphatidyl inositol

A

A.dipalmitoyl lecithin

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7
Q

Ethanolamine is the nitrogenous base of which phospholipid?
A. cardiolipin
B.phosphatidyl inositol
C.lecithin
D.cephalin

A

D.cephalin

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8
Q

What does semiconservative replication mean?
A.replication of DNA takes place at S phase of the cell cycle
B.a DNA molecule is a hybrid of an old strand and one new strand
C.number of DNA molecules is doubled with every other replication
D.replication of DNA never takes place with 100% accuracy

A

B.a DNA molecule is a hybrid of an old strand and one new strand

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9
Q

What are the components of the final product of DNA replication?
A.mRNA, tRNA, and rRNA molecules
B.a wide variety of proteins
C. DNA molecule
D. 2 DNA molecules, each of which contains one new & one old DNA strand

A

D. 2 DNA molecules, each of which contains one new & one old DNA strand

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10
Q

Meselson and StahI used which technique to prove the semi-conservative manner of replication?
A. equilibrium density gradient centrifugation
B. isopycnic centrifugation
C. differential centrifugation
D. diPerential radioisotope labeling

A

A. equilibrium density gradient centrifugation

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11
Q

Which protein unwinds the DNA double helix in E. coli?
A. Dna A
B. Dna B
C. Dna C
D. DnaG

A

B. Dna B

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12
Q

What is the replication fork?
A. only seen in bacterial cells
B. a Y-shaped structure representing the separated strands of DNA to be replicated simultaneously
C. a site where one DNA strand serves as a template, but the other strand is not replicated
D. is created by the action of the enzyme RNA polymerase

A

B. a Y-shaped structure representing the separated strands of DNA to be replicated simultaneously

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13
Q

Which protein prevents the renaturation of the DNA strands once separated to be used as templates in replication?
A.DNA helicase enzyme
B.SSB proteins
C.DNA polymerases
D . ATP

A

B.SSB proteins

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14
Q

Which enzymes used in replication releases the positive supercoil to form negative supercoils?
A. topoisomerases
B.DNA polymerases
C.RNA polymerases
D.DNA ligases

A

A. topoisomerases

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15
Q

Which is the major polymerizing enzyme of replication in E. coli?
A. DNA polymerase III
B. DNA polymerase I
C. DNA polymerase II
D. DNA polymerase IV

A

A. DNA polymerase III

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16
Q

Why does DNA synthesis only proceed in the 5 to 3 direction?
A.DNA polymerases reads the template strand from a 3’ to 5’ direction
B.the 3 “ end of the polynucleotide molecule is more electronegative than the 5 “ end ’G
C. that is the direction in which the two strands of DNA unzip
D. that is the only direction that the polymerase can be oriented

A

A.DNA polymerases reads the template strand from a 3’ to 5’ direction

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17
Q

Which starts the polymerization of each Okazaki fragment?
A.the same RNA primer that began synthesis on the leading strand
B.a DNA primer binding to the template DNA
C. DNA polymerase binding to the template DNA
D. a separate RNA primer

A

D. a separate RNA primer

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18
Q

What is the action of primase in replication?
A. introducing nicks into the DNA double strand in order to prevent the formation of knots
B. hydrolyzing ATP to facilitate DNA unwinding
C. synthesizes short strands of RNA at the site of replication initiation
D. forming a replication fork in the DNA double helix.

A

C. synthesizes short strands of RNA at the site of replication initiation

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19
Q

Which enzyme creates the phosphodiester bonds between Okazaki fragment?
A.RNA polymerase
B.DNA ligase
C. DNA polymerase
D. RNA ligase

A

B.DNA ligase

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20
Q

How is the E. coli chromosome replicated?
A. linear DNA molecule is replicated from multiple origins of replication bidirectionally.
B. linear DNA molecule is replicated from one origin of replication bidirectionally.
C. circular DNA molecule is replicated from one origin of replication bidirectionally
D. circular DNA molecule is replicated from one origin of replication unidirectionally

A

C. circular DNA molecule is replicated from one origin of replication bidirectionally

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21
Q

In which way are the chromosomes of eukaryotic cells replicated?
A. the linear DNA, from multiple origins of replication bidirectionally
B. the linear DNA, from one origin of replication bidirectionally
C. the circular DNA from multiple origins of replication bidirectionally
D. the circular DNA from one origin of replication bidirectionally

A

A. the linear DNA, from multiple origins of replication bidirectionally

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22
Q

Use the figure to answer the corresponding questions.
Which is the correct designation for the DNA strand labeled C is:
A. the leading strand
B. a parental strand
C. Okazaki fragments
D. DNA polymerase

A

C. a parental strand

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23
Q

What molecule are the segments labeled F in the figure above and what are their function?

A.DNA pol 1, synthesizing the leading strand
B.DNA B,forming the replication fork
C.RNA, initiating DNA synthesis
D.helicase, unwinding the DNA double helix

A

C.RNA, initiating DNA synthesis

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24
Q

Capable of folding back on itself like a hairpin and thus acquiring double-stranded characteristics
A. DNA
B. RNA
C. Both DNA and RNA
D. Neither

A

B.RNA

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25
Q

The renal stones in the Pediatric patient with classic xanthinuria were analyzed using?
a.KUB ultrasound
b.X-ray diffractometer
c.ESWL
d.Urine microscopy

A

b.X-ray diffractometer

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26
Q

What detail, that is included in the history of the child with urinary stones found in his diaper, would point to a gene defect?
a. Nausea, vomiting, discomfort
b. Hematuria and passage of stones
c. Parents are relatives
d. Seven months of UTI

A

c. Parents are relatives

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27
Q

Which intermediate is shared both for the synthesis of phospholipids and triacylglycerols?
A. 1,2 diacyglycerol
B.cholesterol
C.HMGCoA
D.glycerol 3 PO4

A

A. 1,2 diacyglycerol

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28
Q

A 3 year old child was brought to the medical center and found to have hepatosplenomegaly, with ataxia, dysarthria, dysphagia, dystonia sometime going into gelastic cataplexy with laughing, supranuclear gaze, dementia and sometimes seizures. What is the nature of the dis- ease?
A. Guacher‘s
B. Niemann Pick’s
C. Krabbe’s
D. Tay Sach‘s

A

B. Niemann Pick’s

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29
Q

Among the following special lipids, which is a glycerophospholipid?
A.cardiolipin
B.galactosyl ceramide
C. GN2
D. sphingomyelin

A

A.cardiolipin

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30
Q

Which protein forms the segment labelled letter D in the figure above and what is its function?
A.DNA ligase, linking short DNA segments
B.DNA pol III, synthesizing the leading strand
C.Helicase, forming the replication fork G
D. Histones, forming nucleosomes

A

A.DNA ligase, linking short DNA segments

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31
Q

What are the segments signified by the letter E in the figure above are, and give how many nucleotides make them?
A.leading fragments, many
B.Okazaki fragments, 1000
C.replication forks, two
D.nucleosomes, eight forming an octamer

A

B.Okazaki fragments, 1000

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32
Q

Which is an important feature of the E. coli DNA polymerase III?
A.can initiate replication without a primer
B.is efficient at nick translation
C.is the major polymerizing enzyme in DNA replication
D.represents over 90% of the DNA polymerase activity in E. coli cells

A

C.is the major polymerizing enzyme in DNA replication

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33
Q

Which is the activity carried by 5’ to 3’ exonuclease actvity of E. coli DNA polymerase I?
A. synthesis of the primers at the DNA replication origin
B. synthesizing the lagging strand
C. proofreading of the replication process
D. polymerizing the gaps in between Okazaki fragments

A

D. polymerizing the gaps in between Okazaki fragments

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34
Q

Which enzyme removes the RNA primer during replication?
A.DNA polymerase IV
B.RNaseH of the DNA polymerase I
C. DNA ligase
D. DNA polymerase II

A

B.RNaseH of the DNA polymerase I

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35
Q

The lagging daughter strand of DNA is synthesized in what appears to be the “wrong” direction. How is this synthesis accomplished?
A.synthesizing short Okazaki fragments in a 5’ — to 3’ direction & forming a loop toward the replication forks
B.synthesizing one short RNA primer to initiate DNA replication
C. using DNA polymerase II to remove RNA primers from Okasaki fragments
D. All of the choices

A

A.synthesizing short Okazaki fragments in a 5’ — to 3’ direction & forming a loop toward the replication forks

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36
Q

Which differentiate Pol I from Pol III?
A. Pol I is an RNA polymerase, while Pol III is a DNA polymerase
B. Pol I has a 3’-5’ exonuclease activity, the other does not
C. Pol I has a lower turnover number, the other has 9000 as its turn over #
D. Pol I utilizes RNA primers, the other does not

A

C. Pol I has a lower turnover number, the other has 9000 as its turn over #

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37
Q

During replication in E. coli, unwinding of DNA is caused by forming positive supercoils which are removed by:
A. DNA ligase, DNA Gyrase
B.DnaB, DNA polymerase
C.DnaB, DNA Gyrase
D.DnaA, DNA Gyrase

A

C.DnaB, DNA Gyrase

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38
Q

Which are the more common secondary structures that might form in the separated DNA strands of replication?
A.basic helix-loop-helix
B.Greek key
C.beta meander
D.stem-loops

A

D.stem-loops

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39
Q

The reaction in DNA replication catalyzed by DNA ligase is:
A.Addition of new nucleotides to the leading strand
B.Addition of new nucleotide to the lagging strand
C.Formation of a phosphodiester bond between the 3’-OH of one Okazaki fragment and the 5’-phosphate of the next on the lagging strand
D.Base pairing of the template and the newly formed DNA strand

A

C.Formation of a phosphodiester bond between the 3’-OH of one Okazaki fragment and the 5’-phosphate of the next on the lagging strand

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40
Q

Which of the following enzymes remove supercoiling in replicating DNA ahead of the replication fork?
A.DNA polymerases
B.Helicases
C.Primases
D.Topoisomerases

A

D.Topoisomerases

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41
Q

A major difference between DNA replication in prokaryotes and eukaryotes is:
A.replication is conservative in prokaryotes
B.there is only one replication origin in prokaryotes
C.prokaryotes do not use Topoisomerase in the replication process
D.DNA amylase performs the function of DNA helicase in prokaryotes

A

B.there is only one replication origin in prokaryotes

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42
Q

What happens after the DNA polymerase laying down a new DNA strand meed up with the RNA primer of a preceding Okazaki fragment?
A. the other strand is then replicated in the 3 to 5’ direction
B.DNA polymerase reverses direction and performs error checking
C.DNA ligase couples the two fragments together
D.the RNA primer is removed and is replaced by DNA

A

D.the RNA primer is removed and is replaced by DNA

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43
Q

Why is an RNA primer necessary for DNA replication?
A. RNA primer is necessary for the activity of DNA ligase
B. RNA primer creates the 5’ and 3’ ends of the strand
C. DNA polymerase can only add nucleotides to RNA molecules
D. DNA polymerase can only add nucleotides to an existing strand with a free 3’ OH group

A

D. DNA polymerase can only add nucleotides to an existing strand with a free 3’ OH group

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44
Q

Patients with no effective medications will develop which long term complication of Von Gierke’s disease:
A.Hyperuricemia
B.Hypercholesterolemia
C.Hepatic adenomas
D.Lactic acidosis

A

C.Hepatic adenomas

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45
Q

Ribonucleotides consist of the following except:
A.Nitrogenous base
B.Ribose sugar
C.Deoxyribose sugar
D.Phosphate group

A

C.Deoxyribose sugar

46
Q

The product of DNA transcription is called:
A.Mature mRNA
B.Introns
C.Exons
D.Primary transcript

A

D.Primary transcript

47
Q

What forces hold the double-stranded DNA together?
A.Hydrophobic interactions
B.Covalent linkages
C.Dipole-dipole interactions
D. Hydrogen bonds

A

D. Hydrogen bonds (will be reviewed)

48
Q

Nucleic acids are polymers of nucleoside monophosphates. They consist of the following, except:
A.A pentose sugar in the furanose form
B.A phosphate group esterified to the sugar
C.A sulfide group ahached to the sugar
D.A nitrogenous base

A

C.A sulfide group ahached to the sugar

49
Q

All the following composes nucleosides, except:
A.Phosphate groups
B.Deoxyribose sugar
C.Ribose sugar
D.Purine bases

A

A.Phosphate group

50
Q

Which of the following has catalytic activity?
A. Nucleotides
B. Phospholipids
C. RNA
D. Phosphate group

A

C. RNA

51
Q

Which of the following statement regarding a double helical molecule of DNA is true?
A.All hydroxyl groups of pentoses are involved in linkages
B.Bases are perpendicular to the axis
C.Each strand is identical
D.Each strand is parallel

A

B.Bases are perpendicular to the axis

52
Q

Transient breaks made by _________ enable the strands of DNA to separate in the absence of he- lix rotation.
A. DNA topoisomerases
B.D-loops
C.5’–>3’ exonucleases
D.DNA gyrases

A

A. DNA topoisomerases

53
Q

Which of the following adds new nucleotides to a growing DNA chain?
A.DNA polymerase
B.DNA helicase
C.primase
D.RNA polymerase

A

A. DNA Polymerase

54
Q

2.Endonucleases, a group of enzymes cleave DNA:
A. Externally
B. Internally
C. Both A and B
D. Neither A nor B

A

B. Internally

55
Q

3.A plasmid consisting of its own DNA with a foreign DNA inserted into it is called:
A. junk DNA
B. recombinant DNA
C. non-coding DNA
D. none of the above

A

B. recombinant DNA

56
Q

4.The first human protein produced through recombinant DNA technology is:
A. somatostatin
B. erythropoeitin
C. interferon
D. insulin

A

D. insulin

57
Q

5.Prior to the production of recombinant insulin, insulin obtained from cows and pigs were given to patients. Some of the problems faced by this treatment was:
A. the insulin was not active
B. in some humans it induced antibody production
C. it reduces the weight of patients
D. loss of memory power

A

B. in some humans it induced antibody production

58
Q

6.An example for autonomously replicating mini chromosome is:
A. virus
B. plasmid
C. phage
D. lichen

A

B. plasmid

59
Q

7.Electrophoresis, a technique used in DNA fingerprinting helps to separate:
A. Tissues
B. DNA segments
C. cells from DNA
D. RNA from DNA

A

B. DNA segments

60
Q

8.cDNA, a term used in recombinant DNA technology means
A. competetive DNA
B. complementary DNA
C. chemical DNA
D. complex DNA

A

B. complementary DNA

61
Q

57.Which of the following statements is true of RNA interference?
a. is a normal way for organisms to regulate gene expression
b. is a mechanism for combating virus infection in plants
c. occurs only in vertebrates
d. is already used therapeutically in many disorders

A

a. is a normal way for organisms to regulate gene expression

62
Q

58.Which of the following is true of the lac operon in E. Coli?
a. The operon is only switched on in the absence of lactose in the growth medium
b. The lac operon messenger RNA is a polycistronic mRNA
c. The enzyme B galactosidase is only produced in large quantities when the lac repressor is bound to the operator
d. The promoter is the binding site for the lac repressor

A

b. The lac operon messenger RNA is a polycistronic mRNA

63
Q

59.Which of the following statements regarding the regulation of trp operon expression by attenuation is correct?
a. The leader peptide sequence encodes enzymes related to tryptophan synthesis
b. The leader peptide sequence contains no tryptophan residues
c. Rapid translation of the leader peptide allows completion of the mRNA transcript
d. Rapid translation of the leader peptide prevents completion of the mRNA transcript

A

d. Rapid translation of the leader peptide prevents completion of the mRNA transcript

64
Q

60.In terms of lac operon regulation, what happens when E. coli is grown in medium containing glucose and lactose?
a. both CAP and the lac repressor are bound to the DNA
b. CAP is bound to the DNA but the lac repressor is not
c. Lac repressor is bound to the DNA but CAP is not
d. Neither CAP nor the lac repressor gene are bound to the DNA

A

d. Neither CAP nor the lac repressor gene are bound to the DNA

65
Q

61.A type of base pair substitution that converts purine-pyrimidine to a
pyrimidine-purine
A. Transition
B. Base analogs
C. Transversions
D. Viruses

A

C. Transversions

66
Q

62.This mutation result from deletion or insertion of nucleotides in DNA that generates altered mRNAs
A. Silent mutations
B. Missense mutations
C. Nonsense mutations
D. Frameshift mutations

A

D. Frameshift mutations

67
Q

63.The type of mutation that only affects the individual in which the mutation arises
A. Somatic mutations
B. Missense mutations
C. Germline mutations
D. Frameshift mutations

A

A. Somatic mutations

68
Q

64.This type of mutation may have no detectable effect because of the
degeneracy of the genetic code
A. Silent mutations
B. Missense mutations
C. Nonsense mutations
D. Frameshift mutations

A

A. Silent mutations

69
Q

65.This type of mutation results in the premature termination of amino acid incorporation into a peptide chain and leads to a shorter polypeptide chain
A. Silent mutations
B. Missense mutations
C. Nonsense mutations
D. Splice site mutations

A

C. Nonsense mutations

70
Q

66.What is the role of the A site in translation?
A. binds to the tRNA holding the growing polypeptide chain of amino acids.
B. binds to incoming to aminoacyl-tRNA which has the anti-codon for the corresponding codon in the mRNA
C. binds to the amino acid that corresponds to the amino terminal end of the growing peptide chain
D. binds to the t-RNA on the acceptor arm of the translation exit site

A

B. binds to incoming to aminoacyl-tRNA which has the anti-codon for the corresponding codon in the mRNA

71
Q

67.The wobble hypothesis allows for non-standard base pairing between:
A. DNA template and RNA transcript
B. codon and anticodon
C. exons and introns
D. template and coding strands

A

B. codon and anticodon

72
Q

68.A mutation in the Shine-Dalgarno sequence will result in:
A. termination of translation in bacteria
B. termination of transcription in eukaryote
C. inhibition or activation of translation in bacteria
D. inhibition of translation in eukaryotes

A

C. inhibition or activation of translation in bacteria

73
Q

69.Which statement is true regarding eukaryotic protein synthesis?
A. Many ribosomes can translate the same mRNA molecule simultaneously.
B. Even before transcription is completed, translation of the mRNA can begin.
C. The 18s rRNA of the 50s ribosomal subunit is responsible for the peptidyltransferase activity that joins the amino acids.
D. Diptheria toxin inhibits prokaryotic but not eukaryotic protein synthesis.

A

C. The 18s rRNA of the 50s ribosomal subunit is responsible for the peptidyltransferase activity that joins the amino acids.

74
Q

70.Which of the following is the first ANTICODON read during translation?
A. UAB
B. UAC
C. GAG
D. AAG

A

B. UAC

75
Q

71.What is the role of the poly-A tail during translation initiation?
A. It stimulates recruitment of the 40s ribosomal subunit to mRNA
B. It recognizes the stop codons during the termination phase of translation
C. It binds to transfer RNA and facilitates peptide bond formation
D. It attaches to the Methionine bound to the methylguanosine cap structure and initiates the transcription of the upstream nucleotide sequences

A

A. It stimulates recruitment of the 40s ribosomal subunit to mRNA

76
Q

72.What molecule once incorporated into the growing chain of DNA halts replication?
A. novobiocin
B. 2’, 3’ dideoxyadenosine triphosphate
C. 2’ deoxycytidine triphosphate
D. actinomycin D

A

B. 2’, 3’ dideoxyadenosine triphosphate

77
Q

73.Primase is the enzyme responsible for:
A. introducing nicks into the DNA double strand in order to prevent the formation of knots
B. hydrolyzing ATP to facilitate DNA unwinding
C. making short strands of RNA at the site of replication initiation
D. forming a replication fork in the DNA double helix.

A

C. making short strands of RNA at the site of replication initiation

78
Q

74.Okazaki fragments are joined together by:
A. RNA polymerase
B. DNA ligase
C. DNA polymerase
D. RNA ligase

A

B. DNA ligase

79
Q

75.A replication fork is:
A. only seen in bacterial cells
B. a Y-shaped structure where both DNA strands are replicated simultaneously
C. a site where one DNA strand serves as a template, but the other strand is not replicated
D. is created by the action of the enzyme RNA polymerase

A

B. a Y-shaped structure where both DNA strands are replicated simultaneously

80
Q

76.Which of the following cause the unwinding of the DNA double helix?
A. DNA polymerase
B. DNA helicase
C. RNA primer
D. primosome

A

B. DNA helicase

81
Q

77.Which of the following best describes semiconservative replication?
A. The replication of DNA takes place at a defined period in the cell cycle
B. A DNA molecule consists of one parental strand and one new strand
C. The number of DNA molecules is doubled with every other replication
D. The replication of DNA never takes place with 100% accuracy

A

B. A DNA molecule consists of one parental strand and one new strand

82
Q

78.At the 5’end, mRNA molecules have a:
A. Poly (A) tail
B. TATA cap
C. 7-methylguanosine cap
D. GCCT tail

A

C. 7-methylguanosine cap

83
Q

79.The RNA sequence that appears in mature RNAs
A. Exons
B. Introns
C. Cap
D. Tail

A

A. Exons

84
Q

80.The TATA box in eukaryotes is located where?
A. 10 bp upstream from the transcription start site (TSS)
B. 35 bp upstream from the TSS
C. 25-30 bp upstream from TSS
D. 5 bp upstream from the TSS

A

C. 25-30 bp upstream from TSS

85
Q

81.The type of RNA polymerase that catalyzes the synthesis of mRNA:
A. Pol I
B. Pol II
C. Pol III
D. Pol IV

A

B. Pol II

86
Q

82.This includes the promoter, RNA-coding region and a terminator:
A. Transcription unit
B. Primary transcript
C. 5’ Flanking sequences
D. 3’ Flanking sequences

A

A. Transcription unit

87
Q

83.The most abundant of all types of RNA comprising about 80% of the total:
A. mRNA
B. tRNA
C. rRNA
D. snRNA

A

C. rRNA

88
Q

84.This structural form of DNA has a left-handed helix that contains about 12 base pairs per turn
A. A form
B. B form
C. C form
D. Z form

A

D. Z form

89
Q

86.Which statement is not true?
A. The single stranded DNA has a higher relative absorbance at at 260 nm
wavelength than does double stranded DNA
B. The melting temperature (Tm) is affected by the number of hydrogen bonds between bases
C. DNA that contains high concentrations of Adenine and Thymine denatures at a lower temperature than Guanine and
Cytosine-rich DNA
D. There are three hydrogen bonds between Adenine and Thymine but only two between Guanine and Cytosine

A

D. There are three hydrogen bonds between Adenine and Thymine but only two between Guanine and Cytosine

90
Q

89.This is the first stage in expression of genetic information
A. Replication
B. DNA synthesis
C. Translation
D. Transcription

A

D. Transcription

91
Q

During DNA finger printing, DNA nucleotides hybridized with probe can be detected through
1. electrophoresis
2. polymerase chain reaction
3. autoradiography
4. hybridoma

A
  1. autoradiography
92
Q

. In DNA finger printing, the DNA from the gel is transferred to ______________ for hybridization
1. nitrocellulose membrane
2. agarose
3. Autoradiogram
4. PCR

A
  1. nitrocellulose membrane
93
Q
  1. In DNA finger printing, even a smallest amount of DNA obtained from samples collected at crime place, can be multiplied into millions of copies by using a technique called
    A. autoradiography
    B southern blotting
    C. polymerase chain reaction
    D. electrophoresis
A
  1. polymerase chain reaction
94
Q

. A radio active probe used in DNA finger printing contains
1. 33 p
2. 14 C
3. 12 N
4. pUC18

A
  1. 33 p
95
Q
  1. A small, 15-30 bases long nucleotide sequences used to detect the presence of complementary sequences in DNA sample during DNA finger printing is called
    A. RFLP
    B Probe
    C. VNTR
    D. reporter gene
A
  1. Probe
96
Q
  1. VNTR is

A. variable nucleotide triplet repeat
B.variable nucleoside tandem repeat
C. variable nucleoside triplet repeat
D.variable number of tandem repeats

A

4.variable number of tandem repeats

97
Q
  1. A technique called southern blotting is used in
    A. monoclonal antibody production
    B. In vitro culture
    C. genetic finger printing
    D. polymerase chain reaction
A
  1. genetic finger printing
98
Q
  1. Using genetic technique in forensic science is also called
    A. genetic finger printing
    B. In vitro culture
    C. hybridoma technology
    D. gene therapy
A
  1. genetic finger printing
99
Q
  1. DNA Ligase, used in recombinant DNA technology is obtained from
    A. E.coli only
    B. E.coli and also Ligase encoded by T4 phage
    C. Saccharomyces
    D. retroviruses
A
  1. E.coli and also Ligase encoded by T4 phage
100
Q
  1. Which one of the following statements about plasmids is correct
    A. plasmids are mobile
    B. plasmids are made up of RNA and proteins
    C. plasmids are present in eukaryotes
    D. plasmids are present in fungi
A
  1. plasmids are mobile
101
Q
  1. Main tools required for recombinant DNA technology are
    A. vector, desired gene
    B. vector, desired gene, mRNA of desired gene, host, restriction enzymes, ligases
    C. desired gene, host, vector
    D. vector, desired gene, mRNA of desired gene, host
A
  1. vector, desired gene, mRNA of desired gene, host, restriction enzymes, ligases
102
Q
  1. Restriction endonucleases recognize specific sequences on DNA called
    A. non-coding sequences
    B. satellites
    C. palindromes with rotational symmetry
    D. tandem repeats
A

D. palindromes with rotational symmetry

103
Q
  1. EcoR1 cleaves DNA at
    A. 5/G AATTC3/
    B. 5/GTT↓AAC3/CTTAA G5/ 3/CAA↑TTG5/
    C. 5/C↓AATTG3/
    D. 5/GGGCC↓T3/3/GTTAA↑C5/ 3/CCCGG↑A5/
A
  1. 5/G AATTC3/
104
Q
  1. Restriction endonucleases are also called
    A. molecular scissors
    B. molecular stichers
    C. DNA synthesis
    D. polymerases
A
  1. molecular scissors
105
Q
  1. Restriction endonucleases, when present in a host cell act on foreign DNA molecule and cleave them, but they do not act on host DNA molecule. It happens because
    A. Restriction endonuclease cannot act on host DNA
    B. Host DNA is packed into chromosomes
    C. Host DNA is methylated hence restriction endonucleases can’t act.
    D. Restriction endonucleases become inactive when they reach host DNA
A
  1. Host DNA is methylated hence restriction endonucleases can’t act.
106
Q
  1. Restriction endonucleases cut DNA at a specific site called
    A. ligation site
    B. Ori
    C. recognition sequence
    D. replication site
A
  1. recognition sequence
107
Q
  1. Which one of the following statements about Restriction Endonuclease is true
    A. all endonucleases cut DNA at specific sites restriction
    B. all restriction endonucleases cut DNA at random sites
    C all restriction endonucleases join DNA segments atspecific sites
    D. all restriction endonucleases join DNA at random sites
A
  1. all endonucleases cut DNA at specific sites restriction
108
Q
  1. Which one of the following statement are not attributed to plasmids
    A. they are circular DNA molecule
    B. they have antibiotic resistant genes
    C. they have the ability of autonomous replication
    D. they have DNA that is as long as chromosomal DNA
A

they have DNA that is as long as chromosomal DNA

109
Q
  1. Which of the following statement about plasmids is correct?
    A. plasmids are present in bacteria , archea& some eukaryotes
    B. plasmids are present in all organisms
    C plasmids present in bacteria and phages
    D. plasmids present in plants and animals
A
  1. plasmids are present in bacteria , archea& some eukaryotes
110
Q
  1. Transfer of recombinant plasmid into E. Coli cells needs
    A heat treatment
    B. UV rays treatment
    C. Cacl2 treatment
    D lysis
A
  1. heat treatment

Biochemisty Main (29 decks)

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