Multiple Choice QuestionsWhat is the source of EcoRI
Escherichia coli R I
Escherichia coli R I 13
Escherichia coli R Y 13
Escherichia coli RX 13
Which one of the following options is a correct match of phenomenon and its explanation
Reverse Transcription PCR - Many copies of a DNA sequence.
Central dogma - RNA > DNA > Protein > RNA.
RNA silencing - Use of ds-RNA to stop the expression of ss-RNA.
Transcription- Process of formation of RNA & proteins.
Assertion : Restriction enzymes cut the strand of DNA to produce sticky ends.
Reason : Stickiness of the ends facilitates the action of the enzyme DNA polymerase.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
C.
If assertion is true but reason is false
A restriction enzyme or restriction endonuclease is an enzyme that cleaves DNA into fragments at or near specific recognition sites within the molecule known as restriction sites. Once restriction enzyme finds a recognition sequence, it binds and cut each of the two strands of the double helix at specific point leaving single stranded portions at the ends. This resulta in the overhanging stretches known as sticky ends.
These are so named because they form hydrogen bonds with their complementary counter parts ,ie, they can join similar complementary ends of DNA fragment from some other source with the help of DNA ligase. This stickiness of the ends facilitates the action of the enzyme DNA ligase, not DNA polymerase.
A tumor inducing plasmid widely used in the production of transgenic plants is that of
Escherichia coli
Bacillus thuringiensis
Staphylococcus aureus
Agrobacterium tumefaciens
cDNA probes are copied from the messenger RNA molecules with the help of
restriction enzymes
reverse transcriptase
DNA polymerase
adenosine deaminase
Assertion : In recombinant DNA technology, human genes are often transferred into bacteria (prokaryotes) or yeast (eukaryote).
Reason : Both bacteria and yeast multiply very fast to form huge populations which express the desired gene.
If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion
If both Assertion and Reason are true but the Reason is not the correct explanation of the assertion
If Assertion is true but Reason is false.
If both Assertion and Reason are false
What is the first step in the Southern Blot technique
Denaturation of DNA on the gel for hybridization with specific probe
Production of a group of genetically identical cells
Digestion of DNA by restriction enzyme
Isolation of DNA from a nucleated cell such as the one from the scene of crime
Restriction enzymes:
are endonucleases which cleave DNA at specific sites
make DNA complementary to an existing DNA or RNA
cut or join DNA fragments
are required in vectorless direct gene transfer.
Which of the following enzymes is used to join bits of DNA?
Ligase
Primase
Endonuclease
DNA polymerase
Polymerase chain reaction is most useful in
DNA synthesis
DNA amplification
protein synthesis
amino acid synthesis
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