One genetic engineering application that relies on transgenic organisms is the production of large quantities of a desired protein, such as the human insulin protein. This process involves the use of restriction enzymes that act like molecular scissors to cut out the gene of interest. Another enzyme called ligase "glues" the gene into the target DNA.True / False.

Restriction enzymes are molecular scissors. These endonucleases serve to cut the DNA at specific sequences called restriction sites. DNA ligases are the enzymes that link DNA fragments together. The DNA of the donor organisms (such as a human) is cut with restriction endonucleases at specific sites to produce a set of the smaller fragments.

The gene of the interest is isolated from these fragments. DNA sequence carrying the gene of the interest is joined to the suitable vector DNA molecule by using DNA ligases. This produces a recombinant vector that carries the gene of the interest into the host cell.

For example, restriction digestion of the human genome is followed by isolation of the human insulin gene from the restriction digestion fragments. The isolated gene is then ligated into the vector DNA using DNA ligases. The vector DNA is inserted into the host cell (such as bacterium E. coli) to produce a large amount of human insulin.