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:

Identify (C) and (D) in the diagram, mention their significance 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

Defining (C) and (D) within the Transcription Unit

(C) → Promoter region

(D) → Terminator sequence

Role in Transcription:

1. Promoter (C):

• The DNA site where RNA polymerase attaches to commence transcription.
• Situated upstream (towards the 5' terminus of the template strand).
• Dictates the initiation site and orientation of transcription.

2. Terminator (D):

• The DNA sequence signaling the cessation of transcription.
• RNA polymerase dissociates from the DNA, releasing the nascent RNA.
• Guarantees the transcription of only the intended DNA segment.

Summary:

Both the promoter and terminator regions are critical for the accurate initiation and termination of gene transcription.