At the start of the elongation phase of translation, the initiating methionyl transfer RNA occupies the:

1. Ribosomes have several named transfer RNA binding sites. 2. Translation begins with the codon AUG, which specifies methionine. 3. The initiating methionyl transfer RNA occupies the P site. 4. It does so at the beginning of the elongation phase of translation. 5. That holds in both prokaryotes and eukaryotes. _Source: OpenStax Biology 2e (CC BY 4.0), Ch 15 'Genes and Proteins', sections 15.1-15.5_