a) Development of Bt cotton has reduced use of insecticides. Justify.
b) Write a note on gene rapy.

a) Bt-cotton plant is a transgenic plant which produces an insecticide against bollworm. Bacillus thuringiensis is the bacterium possess cry gene which is incorporated in the Bt-cotton plant and thus, it produces a crystalline product Bt. The product acts as a toxin when ingested by the pests as it gets activated after reaching the alkaline gut of pests and creates pores in the intestine and kills the pests. The gene provides protection to GMO against budworm, bollworm, beetle, borer, etc. Thus, the development of this plant has reduced the use of insecticides for protection against the pests.