Describe Transcription.
 

Transcription is the process of copying genetic information from one strand of the $DNA$ into $RNA.$

Also the process of transcription is governed by the principle of complementarity, except the adenosine now forms base pair with uracil instead of thymine.

Unlike in replication, which once set in the total $DNA$ of an organism gets duplicated in transcreption only a segment of $DNA$ and only one of the two strands is copied into $RNA$. Reasons why both the strands are not copied at the same time during transcription : $(i)$ If both the strands are copied, they would code because for $RNA$ molecules with different sequences (because complementary does not mean identical) and in turn two proteins with different amino acid sequence would be coding for different proteins and the genetic information transfer machinery would become much more complicated. $(ii)$ The two $RNA$ molecules produced simultaneously would be complementary to each other and hence would bind together to form a double stranded $RNA.$

This world prevent $RNA$ from being translated into protein.