Question

The process of copying the genetic information from one strand of DNA into RNA is termed as transcription. The principle of complementarity of bases governs the process of transcription, also except that uracil comes in place of thymine. Study the complete transcription unit given below and answer the following questions:

Name the main enzyme involved in the process of transcription.

Hint:

RNA polymerase synthesizes the RNA strand using the template DNA strand, creating a complementary sequence that mirrors the coding strand (with uracil replacing thymine).

Answer 1

Enzyme Involved in Transcription 

Answer: The main enzyme involved in the process of transcription is:

RNA Polymerase

Function of RNA Polymerase:

• Binds to the promoter region on the DNA.
• Unwinds the DNA helix to expose the template strand.
• Reads the DNA template and synthesizes a complementary RNA strand.
• Replaces thymine (T) with uracil (U) in RNA.

Additional Notes:

In prokaryotes: A single RNA polymerase performs all types of transcription.
In eukaryotes:

• RNA Polymerase I – synthesizes rRNA
• RNA Polymerase II – synthesizes mRNA
• RNA Polymerase III – synthesizes tRNA and 5S rRNA