Question: during elongation how many trna molecules are held in the ribosome at the same time?
Answer: The next step in translation, called elongation, begins when the ribosome shifts to the next codon on the mRNA. At this point, the corresponding tRNA binds to this codon and, for a short time, there are two tRNA molecules on the mRNA strand. The amino acids carried by these tRNA molecules are then bound together.