How does transcription differ between prokaryotes and eukaryotes in terms of processing?

How does transcription differ between prokaryotes and eukaryotes in terms of processing?

• A. Prokaryotes typically transcribe and translate simultaneously with no introns; eukaryotes transcribe a primary transcript that is capped, spliced, and polyadenylated before translation.
• B. Eukaryotes transcribe and translate simultaneously with introns.
• C. Prokaryotes have introns, eukaryotes do not.
• D. Both process transcripts identically with no modifications.

Answer: (A)

RNA processing differs between prokaryotes and eukaryotes. In bacteria, transcription and translation occur in the same place and can happen at nearly the same time, with transcripts typically ready for immediate translation because they usually contain no introns and do not undergo processing steps like capping or polyadenylation. A single transcript can even encode multiple genes (polycistronic), reflecting a streamlined flow from transcription to protein synthesis. In contrast, eukaryotes separate transcription from translation by enclosing transcription in the nucleus. The initial RNA product, a pre-mRNA, must be processed before it can be translated: a 5' cap is added, introns are removed by splicing, and a 3' poly-A tail is added. Only after this maturation is the mRNA exported to the cytoplasm for translation. This processing is essential for producing a functional message and for regulating gene expression. So the described pattern—prokaryotes transcribing and translating with no introns and eukaryotes producing a capped, spliced, polyadenylated transcript before translation—captures the key difference in transcription-associated processing.

RNA processing differs between prokaryotes and eukaryotes. In bacteria, transcription and translation occur in the same place and can happen at nearly the same time, with transcripts typically ready for immediate translation because they usually contain no introns and do not undergo processing steps like capping or polyadenylation. A single transcript can even encode multiple genes (polycistronic), reflecting a streamlined flow from transcription to protein synthesis.

In contrast, eukaryotes separate transcription from translation by enclosing transcription in the nucleus. The initial RNA product, a pre-mRNA, must be processed before it can be translated: a 5' cap is added, introns are removed by splicing, and a 3' poly-A tail is added. Only after this maturation is the mRNA exported to the cytoplasm for translation. This processing is essential for producing a functional message and for regulating gene expression.

So the described pattern—prokaryotes transcribing and translating with no introns and eukaryotes producing a capped, spliced, polyadenylated transcript before translation—captures the key difference in transcription-associated processing.