Which of the following statements are correct with reference to a transcription unit ? A. A transcription unit in DNA is defined primarily by three regions : promoter, structural gene and terminator. B. The promoter is said to be located towards the 5' -end of the structural gene. C. The promoter is a DNA sequence that provides binding site for RNA polymerase. D. The promoter defines the template and coding strands.

Step-by-step solution

Statement A is correct as a transcription unit in DNA is primarily defined by three regions: a promoter, a structural gene, and a terminator. Statement B is correct because the promoter is located towards the 5' -end (upstream) of the structural gene, with reference to the polarity of the coding strand. Statement C is correct as the promoter is a specific DNA sequence that provides a binding site for RNA polymerase to initiate transcription. Statement D is correct because the presence and position of the promoter i