[问答题]
1.Enzymes are needed for genetic 1w9rn) uptfwu 36d c3bmodification. Outline vglwf g+ 08 +ls4(n*m:segzzzthe role of named enzymes in gene:l(vzf* +n+lm84gegszzw s0g tic modification.
2.Outline the stages of the polymerase chain reaction (PCR).
3.Discuss the potential risks and benefits associated with Bt corn.
