The messenger molecule that carries genetic instructions from DNA to the ribosome is which type of RNA?

• A. DNA
• B. tRNA
• C. rRNA
• D. mRNA

Answer: (D)

The key idea here is how genetic information travels from DNA to the ribosome to direct protein synthesis. Messenger RNA (mRNA) acts as that courier: it’s transcribed from a gene in DNA and carries the encoded instructions in codons to the ribosome, where those codons are read and translated into a specific sequence of amino acids to make a protein.

Other RNA types don’t serve this messaging role. Transfer RNA (tRNA) brings each amino acid to the ribosome in response to codons on the mRNA, matching its anticodon to the codon. Ribosomal RNA (rRNA) is the main structural and catalytic component of the ribosome itself, helping to assemble the protein but not conveying genetic instructions. DNA, meanwhile, is the original genetic material that contains the instructions, but it does not act as the messenger to the ribosome in the cytoplasm.

So the messenger molecule that carries genetic instructions from DNA to the ribosome is mRNA.