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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a-b-c-d-e-f
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a-c-b-d-f-e
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a-c-e-f-b-d
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a-e-c-f-b-d
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Detailed explanation-1: -cDNA is produced in two basic steps: (a) first, mRNA is isolated from other cellular RNA using an elution column. (b) Second, the enzyme reverse transcriptase synthesizes strands of DNA using the mRNA molecules as templates.
Detailed explanation-2: -As a first step, isolated mRNA is converted to a complementary DNA (cDNA) molecule with an RNA-dependent DNA polymerase, also known as reverse transcriptase, during a process called reverse transcription. The cDNA can be used as any other DNA molecule for PCR amplification.
Detailed explanation-3: -cDNA construction To remove the mRNA, the RNAse H enzyme is used to cleave the backbone of the mRNA and generate free 3’-OH groups, which is important for the replacement of mRNA with DNA.
Detailed explanation-4: -Reverse transcriptase is used to make a cDNA copy of the mRNA. The cDNA sample is then amplified by PCR. This yields multiple copies of cDNA without introns. Reverse transcription followed by PCR allows cloning of genes starting from the messenger RNA, and thus, identifying the expressed exons of the eukaryotic gene.