Final answer:
The large ribosomal subunit is responsible for recognizing and rejecting a tRNA that is not correctly matched with an mRNA codon, ensuring the accuracy of protein translation.
Step-by-step explanation:
The component of the ribosome responsible for recognizing a tRNA that is not correctly matched with an mRNA codon is the large ribosomal subunit.
This occurs during the process of translation where the tRNA molecule recognizes a codon on the mRNA, binds to it by complementary base pairing, and adds the correct amino acid to the growing peptide chain.
If a tRNA is not correctly matched, the large subunit plays a critical role in ensuring that the incorrect tRNA does not participate in the translation process, thus maintaining the fidelity of protein synthesis.