During protein synthesis, tRNA molecules deliver amino acids to the A site of the ribosome. These tRNA molecules contain a(n) corresponding to the mRNA. This process usually takes place in the cytoplasm.
The correct answer and explanation is :
The correct answer is anticodon.
Explanation:
During protein synthesis, tRNA molecules play a critical role in translating the genetic information from mRNA into a corresponding sequence of amino acids to form a protein. This occurs in the cytoplasm and involves two key processes: translation and ribosome function.
The mRNA, which was transcribed from DNA, carries the genetic code in the form of codons—sequences of three nucleotide bases that specify which amino acids will be added next in the growing polypeptide chain. Each tRNA molecule has a three-nucleotide sequence known as an anticodon, which is complementary to the codons on the mRNA.
When translation begins, the mRNA binds to the ribosome, and the ribosome reads the mRNA in sets of three nucleotides at a time. The tRNA molecules, each carrying a specific amino acid, enter the ribosome at the A site (aminoacyl site). The anticodon of the tRNA pairs with the complementary codon of the mRNA. This interaction ensures that the correct amino acid is added to the growing polypeptide chain.
For example, if the mRNA codon is AUG (which codes for methionine), the tRNA with the anticodon UAC will bind to it and deliver methionine. After the tRNA has added its amino acid, it moves to the P site (peptidyl site) and the ribosome advances along the mRNA to the next codon. This process repeats, with new tRNA molecules entering the A site, and the polypeptide chain being synthesized.
Thus, the anticodon of tRNA molecules is essential for ensuring the accuracy of protein synthesis. It allows the tRNA to recognize and bind to the correct codon on the mRNA, thereby ensuring the correct sequence of amino acids in the resulting protein.