In polypeptide synthesis, what binds to an mRNA codon?

During polypeptide synthesis, the binding that occurs between the transfer RNA (tRNA) and the mRNA codon is facilitated by the anticodon region of the tRNA. The process begins when mRNA, which carries the genetic information from DNA, is translated into a protein. Each triplet of nucleotides on the mRNA, known as a codon, corresponds to a specific amino acid or stop signal during protein synthesis.

The tRNA molecules have distinct structures that include an anticodon, which is a sequence of three nucleotides that is complementary to a specific mRNA codon. This allows the tRNA to recognize and bind to the appropriate codon on the mRNA strand. As the ribosome moves along the mRNA, the tRNA molecules continuously bring the correct amino acids to form the growing polypeptide chain.

In summary, the anticodon on the tRNA is the key element that directly binds to the codon of the mRNA during the process of translation, ensuring that the correct amino acids are added in the right sequence to synthesize a functional protein.