In the ribosome, what pairs with the codon?

In the ribosome, the anticodon of a transfer RNA (tRNA) molecule pairs with the codon of messenger RNA (mRNA) during the process of translation. Each codon, a sequence of three nucleotides on the mRNA, corresponds to a specific amino acid or a stop signal in protein synthesis. The anticodon is composed of three nucleotides that are complementary to the codon; this complementary pairing ensures that the correct amino acid is brought to the growing polypeptide chain.

Through this interaction, the genetic information encoded in mRNA is accurately translated into a functional protein, highlighting the key role of tRNA in translation. This process not only demonstrates the specificity of nucleic acid interactions but also underpins the fundamental mechanism of gene expression and protein synthesis in living cells.