Which two processes must occur for gene expression?

Which two processes must occur for gene expression?

• A. Transcription and Translation
• B. Replication and Transcription
• C. Translation and Replication
• D. Transcription only

Answer: (A)

Gene expression requires a two-step flow of information: transcription to make messenger RNA from DNA, followed by translation to build a protein from that RNA template. Without transcription, there is no RNA to guide protein synthesis; without translation, the RNA isn’t converted into a polypeptide. Replication copies DNA for cell division and does not produce gene products, so it’s not part of expressing a gene. If you only do transcription, you’d have RNA but no protein; combining with replication still wouldn’t yield a gene product. Therefore, both transcription and translation are needed for gene expression.

Gene expression requires a two-step flow of information: transcription to make messenger RNA from DNA, followed by translation to build a protein from that RNA template. Without transcription, there is no RNA to guide protein synthesis; without translation, the RNA isn’t converted into a polypeptide. Replication copies DNA for cell division and does not produce gene products, so it’s not part of expressing a gene. If you only do transcription, you’d have RNA but no protein; combining with replication still wouldn’t yield a gene product. Therefore, both transcription and translation are needed for gene expression.