how is agrobacteria tumefaciens able to transform a normal plant cell into a tumour

Dear student,

Agrobacterium tumifaciens which is a pathogen and bacteria of several dicot plants delivers a piece of DNA known as T-DNA to the plants  and this T-DNA transforms normal plant cells into a tumor and then direct these tumor cells to produce the chemicals required by the pathogen in the plant. In this way agrobacterium tumifaciens is able to transform a normal plant cell into a tumor by the process of cloning genes in plants and animals.

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