The ribosome binds to mRNA at a specific area. Theribosome starts matching tRNA anticodon sequences to the mRNA codon sequence. Each time a new tRNA comes into the ribosome, the amino acid that it was carrying gets added to the elongating polypeptide chain. This is what I found on google while checking ym answer, and figured this would sound better, so I just used this. This was pasted from https://serc.carleton.edu/microbelife/research_methods/genomics/translat.html
