In the flow of genetic information, which nucleic acid serves as the direct template (blueprint) read by ribosomes to synthesize a specific polypeptide?

Introduction / Context:The central dogma describes information transfer from DNA to RNA to protein. During translation, ribosomes decode a linear RNA sequence in triplet codons to polymerize amino acids into a polypeptide with a defined sequence and function.

Given Data / Assumptions:

• DNA stores long-term genetic information in the nucleus or nucleoid.
• mRNA is a transient copy that carries the coding sequence from DNA to ribosomes.
• rRNA forms the catalytic and structural core of ribosomes; tRNA delivers amino acids.

Concept / Approach:Only messenger RNA contains an ordered series of codons that specify amino acids in a new polypeptide. Ribosomes track along mRNA 5'→3', reading codons and recruiting aminoacyl–tRNAs via anticodon pairing to grow the polypeptide chain.

Step-by-Step Solution:Identify the molecule providing codons to the ribosome: mRNA.Confirm roles of rRNA (catalytic core) and tRNA (adaptor), which support but do not template the amino acid order.Select mRNA as the blueprint.

Verification / Alternative check:Changes (mutations) in the mRNA coding region directly alter the amino acid sequence produced, confirming mRNA serves as the immediate template.

Why Other Options Are Wrong:

• DNA: not read directly by ribosomes.
• rRNA: catalytic/scaffolding roles without coding triplets.
• tRNA: adaptor that does not contain full gene coding sequence.
• snRNA: splicing factor in eukaryotes, not a translation template.

Common Pitfalls:Assuming DNA is translated; in cells, translation uses RNA, not DNA.

Final Answer:mRNA