Class 12th Biology 2016 Set2 Delhi Board Paper Solution
Question 21
How has RNAi technique helped to prevent the infestation of roots in tobacco plants by a nematode ?
Answer
Using Agrobacterium vectors, nematode specific genes were introduced into the host plant. This DNA produced both sense and anti sense RNA in the host cells. These two RNAs being complementary to each other formed a double strand (dsRNA) that initiated RNAi and thus silenced the specific mRNA of the nematode. Hence the parasite could not survive in the transgenic host.
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