THE MOLECULAR BASIS OF INHERITANCE
RECOMBINANT DNA
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Ligase enzyme
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Reverse Transcriptase enzyme
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Restriction Endonuclease enzyme
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DNA polymerase enzyme
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Detailed explanation-1: -Alternatively, the first-strand cDNA can be made double-stranded using DNA Polymerase I and DNA Ligase. These reaction products can be used for direct cloning without amplification.
Detailed explanation-2: -cDNA is not genomic DNA, because the transcript of genomic RNA has been processed (i.e., it lacks promoters and introns). The enzyme reverse transcriptase (see Chapter 15) is used to synthesize double-stranded DNA that is a complementary copy of the mRNA.
Detailed explanation-3: -In molecular biology, complementary DNA (cDNA) is synthesised from an RNA template in a reaction catalysed by the enzyme reverse transcriptase (RTase).
Detailed explanation-4: -Once the mRNA is dissolved away with NaOH, DNAPol I is added, which uses the double-stranded region as a primer for synthesis of a new DNA strand. The single-stranded portion of the loop is cut with an S1 nuclease, and the result is a double-stranded cDNA copy of the mRNA.