The correct option is
B A- Restriction endonuclease, B- Restriction endonuclease, C- DNA ligase, D- Transformation
Recombinant DNA (rDNA) is a modified DNA molecule that has DNA segments from multiple biological sources. The technology used for producing recombinant DNA (rDNA) is referred to as recombinant DNA technology.
To create recombinant DNA, several biological tools such as enzymes and DNA from at least two sources are required.
Steps to create rDNA include the following:-
Step-1. Isolation and modification of gene of interest:
The gene of interest is isolated from the purified DNA, modified by PCR.
Step-2. Cutting the gene at the recognition sites:
Restriction enzymes are the endonucleases that cleave the phosphodiester bonds present between the nucleotides within or near to specific DNA sequences that they identify, called recognition sites.
Step-3. Ligation of DNA Molecules:
The DNA fragments produced are ligated with the help of the enzyme DNA ligase. This results in the formation of recombinant DNA.
Step-4. Transfer of the rDNA into the suitable host:
The rDNA created is introduced into the host cell for the production of the desired protein/ product. This is known as transformation.
Therefore, in this question:
- A and B are the restriction endonucleases that cut foreign DNA and vectors, i.e., plasmid DNA in this case.
- ‘C’ is the enzyme DNA ligase that joins the DNA fragments.
- ‘D’ is the transformation process in which E.coli is taking up foreign DNA.
Exonucleases cleave phosphodiester bonds between consecutive nucleotides of DNA at their terminal ends (either 5’ or 3’), usually one nucleotide at a time.
Hydrolases are a class of enzymes that catalyse the breakdown of bonds using water.
Transduction is the process by which a bacterium takes up the genetic material with the help of a bacteriophage.