Below are the steps involved in cloning gene sequences using mRNA.Arrange the steps in the appropriate order.
1)The double-stranded cDNA is treated with a restriction endonuclease to generate compatible ends for annealing and ligation.
2)mRNA is isolated from the cell and converted back into double-stranded sequences using reverse transcriptase to generate complementary DNA.
3)The RNA-DNA hybrid is treated with a nuclease to cleave the RNA strand,producing RNA fragments.
4)Reverse transcriptase completes the single-stranded cDNA when it reaches the end of the mRNA transcript.
5)RNA fragments serve as primers for DNA synthesis of the second strand of cDNA using DNA polymerase.
A)4,2,1,5,3
B)2,4,3,5,1
C)2,3,5,4,1
D)3,2,5,4,1

Question

Below are the steps involved in cloning gene sequences using mRNA.Arrange the steps in the appropriate order.
1)The double-stranded cDNA is treated with a restriction endonuclease to generate compatible ends for annealing and ligation.
2)mRNA is isolated from the cell and converted back into double-stranded sequences using reverse transcriptase to generate complementary DNA.
3)The RNA-DNA hybrid is treated with a nuclease to cleave the RNA strand,producing RNA fragments.
4)Reverse transcriptase completes the single-stranded cDNA when it reaches the  end of the mRNA transcript.
5)RNA fragments serve as primers for DNA synthesis of the second strand of cDNA using DNA polymerase.
A)4,2,1,5,3 
B)2,4,3,5,1 
C)2,3,5,4,1 
D)3,2,5,4,1

Quizplus · Accepted Answer

The first step is to isolate mRNA from the cell and generate complementary DNA (Step 2). Reverse transcriptase completes the single-stranded cDNA when it reaches the end of the mRNA transcript (Step 4). The double-stranded cDNA is treated with a restriction endonuclease to generate compatible ends for annealing and ligation (Step 1). RNA fragments serve as primers for DNA synthesis of the second strand of cDNA using DNA polymerase (Step 5). Finally, the RNA-DNA hybrid is treated with a nuclease to cleave the RNA strand, producing RNA fragments (Step 3). Therefore, the correct order is 2, 4, 1, 5, 3 or choice B.

Below Are the Steps Involved in Cloning Gene Sequences Using