What molecule carries the genetic message from DNA to the ribosome?

• A. Amino acid
• B. mRNA
• C. tRNA
• D. Codons

Answer: (B)

The main idea here is how genetic information moves from DNA to protein. Messenger RNA acts as the intermediary that carries the gene’s message from DNA in the nucleus to the ribosome in the cytoplasm. During transcription, DNA is used to synthesize a complementary mRNA strand. This mRNA then provides a code in sets of three nucleotides called codons, which the ribosome reads to assemble the correct sequence of amino acids into a protein.

Amino acids are the building blocks of proteins, not the information carrier. tRNA helps bring the right amino acids to the ribosome and recognizes codons on the mRNA, but it is the mRNA that conveys the genetic information to specify the order of those amino acids. Codons are the reading units on the messenger RNA, not the carrier of the message itself.