Question

In genetic engineering, "sticky end" refers to ___________.

1) a technique for finding a gene of interest within a nucleus without destroying the cell
2) short bits of single-stranded DNA left at the end of DNA molecules cut by restriction enzymes
3) none of the above
4) the ability of plasmids to stick to a bacterial cell wall and thus be taken up into the bacterium
5) the site on mRNA that sticks to the DNA during transcription

Answer 1

A 'sticky end' in genetic engineering is a short single-stranded overhang created by restriction enzymes on DNA fragments, which allows for the annealing and ligation of complementary DNA sequences during recombinant DNA technology. The correct option is B.

Step-by-step explanation:

In genetic engineering, a "sticky end" refers to short bits of single-stranded DNA left at the end of DNA molecules cut by restriction enzymes.

These ends are termed sticky because they can form hydrogen bonds with complementary sticky ends of DNA fragments cut by the same restriction enzyme, which is essential for recombinant DNA technologies.

The process involves using a restriction enzyme to create these sticky ends on both the foreign DNA and vector DNA, such as a plasmid.

After the sticky ends anneal, or base pair, DNA ligase is used to permanently join the DNA fragments by reattaching the DNA backbones, forming recombinant DNA. The correct option is B.