This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Translation, Subject name: Biochemistry
High energy phosphates required to form one peptide bond: 
Select and explain. 
A. 2, B. 4, C. 6, D. 8
B: 4
Answer: B: 4 
Explanation: 2 ATP & 2 GTP (Total 4 high energy phosphates) required to add 1 amino acid in a growing polypeptide chain. Energy required Function 2 ATP Activation of each amino acid 1 GTP For entry at -site of ribosome during elongation of translation 1 GTP For translocation