Attachment of an amino acid to a tRNA molecule. The amino acid (shown in blue) is esterified to the 3′-hydroxyl group of the terminal adenylate of tRNA.
[Source: J. L. Tymoczko, J. Berg, and L. Stryer, Biochemistry: A Short Course, 2nd ed. (W. H. Freeman and Company, 2013), Fig. 39.3.]