Explanation

Transformation is a process by which free DNA is incorporated into a recipient bacterial cell and brings about genetic change. During the process of transformation, genes are transferred from one bacterium to another as ‘naked DNA’ in solution. The first evidence of bacterial transformation was obtained by the British scientist Fredrick Griffith in the late 1920s while working on $Streptococcus\ pneumoniae\$ $(Pneumococcus)$. Hence, transformation is also referred to as ‘Griffith effect’.