Cooperativity of Hb a Deoxy-hemoglobin is relatively uninterested in oxygen, but when one oxygen attaches, the second binds more easily, and the third and fourth easier yet The same process works in reverse: once fully loaded hemoglobin lets go of one oXygen, it lets go of the next more easily, and so forthCooperativity of Hb ◼ Deoxy-hemoglobin is relatively uninterested in oxygen, but when one oxygen attaches, the second binds more easily, and the third and fourth easier yet. ◼ The same process works in reverse: once fully loaded hemoglobin lets go of one oxygen, it lets go of the next more easily, and so forth