Scientists in Australia have genetically modified cotton plants to produce a toxin from the bacterium Bacillus thuringiensis (Bt). This toxin is harmful to insect pests that feed on the cotton plants. Which enzyme is used to join the Bt gene into the cotton plant DNA?

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Question

Scientists in Australia have genetically modified cotton plants to produce a toxin from the bacterium Bacillus thuringiensis (Bt). This toxin is harmful to insect pests that feed on the cotton plants. Which enzyme is used to join the Bt gene into the cotton plant DNA?

Accepted Answer

Ligase — Award 1 mark for ligase. Ligase enzyme joins DNA fragments together by forming bonds between the sugar-phosphate backbones. A is incorrect because restriction enzymes cut DNA rather than join it. C is incorrect because DNA polymerase is used to replicate DNA, not to join different DNA fragments. D is incorrect because protease breaks down proteins, not DNA.

Answer

Protease

Answer

Ligase

Answer

DNA polymerase

Answer

Restriction enzyme

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