Transcription

Definition

Transcription is the process by which a segment of DNA is copied into RNA by the enzyme RNA polymerase. It is the first step in gene expression, allowing genetic information to be transcribed for protein synthesis.

5 Must Know Facts For Your Next Test

1. Transcription occurs in three main stages: initiation, elongation, and termination.
2. RNA polymerase binds to the promoter region of a gene to initiate transcription.
3. The resulting RNA strand is complementary to the DNA template strand and is synthesized in a 5' to 3' direction.
4. In prokaryotes, transcription and translation can occur simultaneously, whereas in eukaryotes, transcription occurs in the nucleus and translation occurs in the cytoplasm.
5. Various types of RNA are produced through transcription, including mRNA, tRNA, and rRNA.

Review Questions

• What are the main stages of transcription?
• How does RNA polymerase recognize where to start transcription?
• What are the differences between transcription in prokaryotes and eukaryotes?

Related terms

RNA Polymerase:

An enzyme that synthesizes RNA from a DNA template during transcription.

Promoter:

A specific DNA sequence where RNA polymerase binds to initiate transcription.

mRNA (messenger RNA): The type of RNA that carries genetic information from DNA to the ribosome for protein synthesis.