Which statement best describes the flow of genetic information in the Central Dogma?

Which statement best describes the flow of genetic information in the Central Dogma?

• A. DNA is transcribed into RNA, which is translated into proteins.
• B. RNA is transcribed into DNA, which becomes lipids.
• C. Proteins are transcribed into RNA, which becomes DNA.
• D. DNA directly becomes proteins without RNA.

Answer: (A)

The essential idea is that genetic information flows from DNA to RNA to protein. DNA is first transcribed into RNA, producing a messenger RNA that carries the genetic code. This RNA is then translated at ribosomes into a chain of amino acids, forming a protein. In eukaryotes, transcription happens in the nucleus and translation in the cytoplasm (prokaryotes lack a nucleus, so processes occur more directly in the cytoplasm). The other scenarios violate this two-step path: RNA does not become DNA to guide lipids, and proteins are not produced directly from DNA without the RNA intermediary. Thus, DNA → RNA → protein best captures how genes specify proteins.

The essential idea is that genetic information flows from DNA to RNA to protein. DNA is first transcribed into RNA, producing a messenger RNA that carries the genetic code. This RNA is then translated at ribosomes into a chain of amino acids, forming a protein. In eukaryotes, transcription happens in the nucleus and translation in the cytoplasm (prokaryotes lack a nucleus, so processes occur more directly in the cytoplasm). The other scenarios violate this two-step path: RNA does not become DNA to guide lipids, and proteins are not produced directly from DNA without the RNA intermediary. Thus, DNA → RNA → protein best captures how genes specify proteins.