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RBCs possess many adaptations to facilitate maximal unloading of oxygen at peripheral tissues with maximal transport of CO2 back to the lungs. The Bohr effect facilitates the rightward shift of the oxyhemoglobin dissociation curve (thereby increasing the P50 of hemoglobin), where oxygen is more easily unloaded with increased levels of 2,3-DPG. Meanwhile, the Haldane effect refers to the increased affinity for CO2 that deoxyhemoglobin has when compared with oxyhemoglobin. This optimizes transport of CO2 from the periphery (deoxygenated hemoglobin picks up a maximum amount of CO2 at peripheral tissues), and also optimizes the amount of CO2 unloading that occurs in the lungs (oxygenated hemoglobin will have a lower affinity for CO2 and will therefore unload CO2 in the lungs). This change in affinity is made possible via a rightward shift in the carbonic acid-bicarbonate buffer equation such that H+ is produced, thus increasing the affinity of CO2 for hemoglobin.