Difficulty: Easy
Correct Answer: mRNA
Explanation:
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:
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:
Common Pitfalls:
Assuming DNA is translated; in cells, translation uses RNA, not DNA.
Final Answer:
mRNA
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