171.

What 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

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