Which molecule carries genetic information from DNA to the ribosome for protein synthesis?

Which molecule carries genetic information from DNA to the ribosome for protein synthesis?

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

Answer: (D)

The flow of genetic information from DNA to the site of protein assembly relies on a messenger molecule that carries the encoded instructions. During transcription, the DNA sequence is copied into an mRNA strand, which then exits the nucleus and travels to the ribosome. The ribosome reads mRNA codons—three-nucleotide units that specify each amino acid—and coordinates the assembly of a protein. Transfer RNA brings the appropriate amino acids by pairing its anticodons with the mRNA codons, while ribosomal RNA forms the platform and helps catalyze peptide bond formation. DNA remains the original code inside the nucleus, and tRNA and rRNA perform decoding and assembly roles, but only mRNA provides the actual message that directs the protein sequence.

The flow of genetic information from DNA to the site of protein assembly relies on a messenger molecule that carries the encoded instructions. During transcription, the DNA sequence is copied into an mRNA strand, which then exits the nucleus and travels to the ribosome. The ribosome reads mRNA codons—three-nucleotide units that specify each amino acid—and coordinates the assembly of a protein. Transfer RNA brings the appropriate amino acids by pairing its anticodons with the mRNA codons, while ribosomal RNA forms the platform and helps catalyze peptide bond formation. DNA remains the original code inside the nucleus, and tRNA and rRNA perform decoding and assembly roles, but only mRNA provides the actual message that directs the protein sequence.