Question

The tool of genetic engineering which makes it successful is
A. DNA polymerase
B. Permease
C. Restriction endonuclease
D. Topoisomerase

Answer 1

Hint: Genetic engineering deals with the production and marketing of products with the help of cells of living organisms or whole organisms using different enzymes. It works by modifying DNA by recombinant DNA techniques to produce genetically modified organisms.

Complete answer:
In genetic engineering, genetically modified organisms are produced by the process of DNA recombination. In this process, a plasmid or vector is used to isolate foreign DNA into the host cell with the help of enzymes, and then the isolated DNA is purified. The enzymes involved in this process play a very important role.
Restriction enzymes, also known as restriction endonucleases, are proteins produced by bacteria. They cut DNA at specific points along the chain in a precise manner. They have the capability to identify these specific points by looking at the particular arrangements of the base pair of DNA at that location known as a restriction site. They detect the required sequence and cut the DNA from that point, thus are also known as molecular scissors. The sequences recognized by these enzymes are known as palindromes which read two strands in the opposite directions. Thus, we can say that Restriction endonucleases are a powerful tool for genetic engineering.

So the correct option is (C) Restriction endonuclease.

Additional information: These enzymes help the bacteria to restrict certain infections caused by viruses (bacteriophages), thus get the name restriction enzymes. They destroy the viral DNA of bacteriophage without damaging their own bacterial DNA. Each bacterium has a unique restriction enzyme.

Note:
There are thousands of restriction enzymes discovered so far. These enzymes are unique and thus act only at a specific sequence of base-pairs (A & T and C & T). There are four major types of restriction enzymes based on structure, cleavage site, and specificity, and are named Type I, II, III, and IV.