What is the primary function of messenger RNA (mRNA)?

What is the primary function of messenger RNA (mRNA)?

• A. Carries genetic information from DNA to ribosome for protein synthesis
• B. Transports amino acids to ribosome
• C. Forms part of the ribosome's catalytic center
• D. Regulates gene expression by binding DNA

Answer: (A)

mRNA's primary role is to serve as the messenger that carries the genetic instructions encoded in DNA from the nucleus to the ribosome where proteins are built. During transcription, a copy of a gene is made into mRNA, which then travels to the ribosome. The ribosome reads the mRNA in codons, groups of three nucleotides, and uses that information to assemble the corresponding sequence of amino acids, with transfer RNA bringing each amino acid to the growing protein chain. This flow—DNA to mRNA to protein—explains why mRNA is described as the carrier of information for protein synthesis. The other functions belong to different molecules: transporting amino acids is the job of tRNA; forming part of the ribosome’s catalytic center is rRNA; and regulating gene expression by binding DNA is done by DNA-binding proteins.

mRNA's primary role is to serve as the messenger that carries the genetic instructions encoded in DNA from the nucleus to the ribosome where proteins are built. During transcription, a copy of a gene is made into mRNA, which then travels to the ribosome. The ribosome reads the mRNA in codons, groups of three nucleotides, and uses that information to assemble the corresponding sequence of amino acids, with transfer RNA bringing each amino acid to the growing protein chain. This flow—DNA to mRNA to protein—explains why mRNA is described as the carrier of information for protein synthesis. The other functions belong to different molecules: transporting amino acids is the job of tRNA; forming part of the ribosome’s catalytic center is rRNA; and regulating gene expression by binding DNA is done by DNA-binding proteins.