Which sequence best describes the central dogma and the primary roles of transcription and translation?

• A. DNA to RNA to protein; transcription makes RNA from DNA; translation makes proteins from RNA.
• B. DNA to protein to RNA; transcription makes protein from RNA.
• C. RNA to DNA to protein; transcription makes RNA from DNA.
• D. RNA to protein to DNA; transcription makes RNA.

Answer: (A)

The main idea being tested is how genetic information flows and how transcription and translation work. In the standard view, information moves from DNA to RNA to protein. Transcription is the process that makes an RNA copy from a DNA template, with RNA polymerase synthesizing an RNA strand complementary to the DNA. Translation then reads that RNA, using the genetic code to assemble amino acids into a protein, guided by tRNA and the ribosome. This sequence—DNA to RNA to protein—describes how genetic information is copied and then interpreted to produce functional molecules.

The other statements try to place the steps in the wrong order or assign the wrong role to the processes (for example, making protein directly from DNA or from RNA without the intermediate RNA template). The standard flow and roles, as described, best explain how cells convert genetic information into functional proteins.