Which of the Following Seems to Account for Most of the Non-Protein-Coding

Question

Which of the following seems to account for most of the non-protein-coding DNA?
A)"junk" DNA that serves no possible purpose
B)rRNA and tRNA coding sequences
C)DNA that is translated directly without being transcribed
D)non-protein-coding DNA that is transcribed into several kinds of small RNAs with biological function
E)non-protein-coding DNA that is transcribed into several kinds of small RNAs without biological function

Accepted Answer

Non-protein-coding DNA that is transcribed into several kinds of small RNAs with biological function seems to account for most of the non-protein-coding DNA. This includes microRNAs, siRNAs, and piRNAs, which play important roles in gene regulation, chromosome structure, and genome defense. Therefore, this DNA is not just "junk" but has an important function in the cell.