Read the following statements regarding transcription.
1. RNA polymerase initiates the process of transcription with the help of sigma factor.
2. RNA polymerase also facilitates opening of the DNA double helix in prokaryotes.
3. Transcription requires primer
4. In bacteria, there are three types of RNA polymerases.
How many of the above statements are incorrect?

The correct option is A 2
Transcription is the process of copying genetic information from one strand of the DNA (template strand) into RNA.

The process of transcription in bacteria involves three steps and is performed with the help of RNA polymerase enzyme as follows:
i. Initiation- the process of transcription initiates at the promoter site in the transcription unit with the help of sigma factor of RNA polymerase.
ii. Elongation- RNA polymerase also facilitates opening of the DNA helix and continues elongation. The structural gene gets transcribed to RNA.
iii. Termination- the process of transcription gets terminated at the site of the terminator region which is towards the 3' end of the coding strand of DNA, where RNA polymerase encounters the rho factor.

The transcribed RNA gets released and DNA gets its double helix structure back again.

Transcription does not require primer. The DNA replication process is where the RNA primer is required (primers are short oligonucleotides).

In bacteria, there is only one type of RNA polymerase that catalyses transcription of all types of RNA.

However, in eukaryotes, there are three types of RNA polymerases.
RNA polymerase I, which transcribes rRNA.
RNA polymerase II, which is responsible for the transcription of hnRNA.
RNA polymerase III, which is responsible for the transcription of tRNA, 5srRNA and snRNA (small nuclear RNA).

Hence, two statements are incorrect (3 and 4).