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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Affinity for O2 in the blood depends on?
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The correct answer is  Ans. a (2-3 diphosphoglycerate). (Ref. Ganong, Physiology, 21 st/pg.537)2-3 DPG/ 2-3 BPG is essential for normal transport function of Hb, eg., storing blood in acid citrate dextrose (formerly used medium) leads to decreased 2, 3 DPG in RBCs and such blood displays an abnormally high oxygen affinity, acting virtually as an oxygen "trap" rather than oxygen transport system, failing to unload properly its bound oxygen in tissues.However, decrease in 2-3 DPG can be prevented by adding inosine to storage medium as it can enter RBC where it is converted to 2, 3 DPG.