disable a gene? I have asked this question already but i didn't really get answers I could understand. This is a six mark question in a biology assignment.

"'Flavr Savr' tomatoes are tomatoes that have been genetically modified so that they take longer than normal to ripen. This has been achieved by disabling a critical tomato gene so that it fails to produce a protein needed for ripening. In order to disable the gene, a start codon is inserted in the beginning of a nonsense strand so that both the sense and nonsense strand are copied into mRNA.
Suggest why this will prevent a polypeptide from being produced.

I have absolutely no idea where to start with this question, please help!

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