Question

How do you transcribe DNA into mRNA?

Answer 1

Hint: Transcription is a process in which the information from a DNA strand is copied into RNA with the help of enzyme RNA polymerase.

Complete answer:
Transcription occurs with the help of a transcription unit that consists of a promoter, terminator, and a structural gene.

The initiation of transcription starts by binding enzyme RNA polymerase to the promoter region of the transcription unit and converts the double-stranded DNA into single strands.

The next step of transcription is elongation where the RNA polymerase moves along the template strand which is also known as the non-coding strand and it starts complementary pairing of bases to make an RNA copy which is exactly similar to the coding strand only the direction is opposite.

In the last step of transcription the RNA polymerase reaches the terminator of the transcription unit after which the RNA polymerase gets separated.
In prokaryotes, the transcribed mRNA does not require any further processing whereas in eukaryotes the mRNA requires the processing of mRNA to become active. The processing includes splicing, capping, and tailing of mRNA.

Note: Transcription is not similar to DNA replication because DNA replication involves the replication of entire DNA whereas in transcription only one strand of DNA is copied into RNA. The DNA strand running in 3' to 5'direction is known as the template strand and the strand running in 5'to 3' is known as the coding strand. The sequence of RNA formed is similar to the coding strand where the only difference is that the thymine is replaced by uracil in the RNA.