Changes in the dna sequence that affect the expression of genetic information are called

What is the problem in this article? what solution does the article propose?

Which of the following will a bacterium produce when a human gene is added to its genome? question 4 options: human carbohydrates a protein made up of both human and bacterial properties the human protein coded for by the human gene human plasmids that can be isolated from the bacterium

Which enzyme is responsible for “unzipping" the dna by breaking the hydrogen bonds between the nucleotides?