This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardiovascular system, Subject name: Physiology
[{'content': '2,3 DPG binds to_____ site of Hb and____ release of O2 \nSelect and explain. \nA. One, increase, B. Four, increase, C. One, decrease, D. Four, decrease', 'role': 'user'}, {'content': 'Answer: A \nExplanation: 2,3 DPG is a highly charged anion that binds to beta chain of deoxyHb. One mole of deoxyHb binds to one mole of 2,3 DPG. An increase in concentration shifts the reaction to right causing more O2 to be liberatedRef: Ganong&;s Review of medical physiology, 25th edition. page no.641', 'role': 'assistant'}]