Initiation of transcription in eukaryotes requires assembling RNA polymerase II at the gene’s promoter with promoter-bound transcription factors. These factors recognize promoter elements and recruit RNA polymerase II to form the pre-initiation complex, properly orienting the enzyme to start RNA synthesis. Additional players like the Mediator complex and chromatin remodelers help make the promoter accessible and regulate the process, and TFIIH opens the DNA and phosphorylates the polymerase to start elongation. This coordinated assembly at the promoter explains why transcription begins only after promoter-bound transcription factors recruit RNA polymerase II, not by RNA polymerase II acting alone, not by ribosomes, and not by DNA polymerase. The other options describe processes that do not initiate transcription in this way.

DNA’s role in growth is to provide the genetic blueprint that is faithfully copied and passed to daughter cells during division. As an organism grows, cells proliferate, and each new cell must receive an identical set of genes to function properly. DNA is replicated so the same genetic information is present in all descendants, guiding development and maintenance of tissues. While proteins that carry out growth are made later through transcription and translation, and energy for growth comes from cellular metabolism, DNA itself is not a source of energy or nutrients, nor does it directly build proteins. That faithful replication and distribution of genetic SAMPLEinformation is why this statement best describes DNA’s role in organismal growth.

Telomeres act like protective caps at chromosome ends, and their length limits how many times a cell can divide. In germ cells and many stem cells, telomerase is active, so these cells can add back telomere repeats each time they divide. This keeps telomeres long enough to support many rounds of division, which is essential for producing gametes and for tissue renewal in the body. In contrast, most somatic cells repress telomerase, so with each division telomeres shorten. Over time this leads to a limit on cell divisions, contributing to aging and reduced regenerative capacity. Some cancers reactivate telomerase, enabling continued division. The idea that telomerase is active in all somatic cells to prevent aging isn’t accurate, and the notion that it’s only in bacteria doesn’t match how eukaryotic telomere maintenance works.

Protein-coding genes contain the instructions to build proteins. Their DNA sequence is transcribed into messenger RNA, which is then translated by ribosomes to assemble a specific sequence of amino acids, producing a protein. The information in these genes directly determines the identity and sequence of the protein product, guiding how the cell functions. Others describe what proteins can do or what the cell uses for energy, not what the genes themselves encode. Enzymes are proteins that catalyze reactions, energy storage is handled by molecules like ATP and fats, and while some proteins end up in membranes, genes themselves don’t become part of the membrane—the proteins they encode may.