The diagram shows some stages involved in genetic engineering. Which row correctly identifies W, X, Y and Z?

Answer:

1) E

W is a section of the chromosome. It is not the entire chromosome, so it has to represent a gene.
X represents restriction enzymes that cut DNA into smaller fragments at certain specific nucleotide sequences.
Y represents plasmid which is circular DNA of bacteria.
Z represents ligase which connects the DNA taken from the chromosome and the plasmid DNA.