a hemoglobin molecule can bind up to four oxygen molecules on the iron atom in a heme group and experiences cooperative binding, which means that as oxygen molecules are added to one heme group, it is easier to add another oxygen molecule to one of the other heme groups. in other words, through cooperative binding, once a deoxyhemoglobin molecule, which has a low affinity for oxygen, starts to bind oxygen it more easily binds additional oxygen molecules and once a hemoglobin molecule starts to release oxygen, it more readily releases additional oxygen. how does cooperative binding relate to oxygen use during rest and strenuous exercising? (choose all that apply)