Which molecule contains codons that specify amino acids?

Which molecule contains codons that specify amino acids?

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

Answer: (A)

Codons are three-nucleotide units that determine which amino acids are added during protein synthesis, and these codons are read on messenger RNA during translation. The ribosome moves along the mRNA, encountering each codon, and a matching tRNA brings the appropriate amino acid by pairing its anticodon with the codon. DNA holds the genetic information that will be transcribed into mRNA, but the actual codon sequences used to specify amino acids exist on the mRNA, not on DNA. rRNA forms part of the ribosome and helps the process run, while tRNA carries the amino acids themselves but does not carry the codon messages in the same way. So the molecule that contains codons that specify amino acids is messenger RNA.

Codons are three-nucleotide units that determine which amino acids are added during protein synthesis, and these codons are read on messenger RNA during translation. The ribosome moves along the mRNA, encountering each codon, and a matching tRNA brings the appropriate amino acid by pairing its anticodon with the codon. DNA holds the genetic information that will be transcribed into mRNA, but the actual codon sequences used to specify amino acids exist on the mRNA, not on DNA. rRNA forms part of the ribosome and helps the process run, while tRNA carries the amino acids themselves but does not carry the codon messages in the same way. So the molecule that contains codons that specify amino acids is messenger RNA.