Final answer:
Elements adjacent to a regulatory element that control the transcription of a gene are known as cis-acting elements. They include transcription factor binding sites near the promoter region as well as distal enhancers within introns or far from the gene. The correct answer to the student's question is A. Cis-acting elements.
Step-by-step explanation:
Understanding Regulatory Elements in Gene Expression
Elements that are situated near the regulatory element of a gene and are involved in the control of that gene's transcription, are known as cis-acting elements. These DNA sequences are located on the same chromosome and adjacent to the gene they regulate. Common examples of cis-acting elements include transcription factor binding sites within the promoter region. These sites can be very close to the promoter, such as the TATA box, CAAT box, and GC box, which are within a few hundred base pairs upstream of the transcriptional start site. Alternatively, they can be more distal, like enhancers, which can even be located within introns or thousands of base pairs away from the gene, yet still influence transcription through DNA looping mechanisms.
The correct identification for elements near the regulatory element that may be part of the translated region, but nearby to an mRNA transcript is A. Cis-acting elements. These include promoter-proximal elements and distal elements like enhancers. They are distinguished from trans-acting factors, which are typically proteins that can influence gene expression but are not directly tethered to the gene's DNA sequence.