Hemoglobin binds bisphosphoglycerate (bpg) and oxygen at different locations. the protein itself changes conformation upon binding of bpg. allosteric modifiers, like bpg, can change the shape (conformation) and usually the activity of a protein upon binding. a) at increased levels of bpg, which direction would you expect the binding curves of oxygen to shift? b) how does bpg affect the total amount of o2 that can bind? c) how does bpg affect the affinity of o2 binding to hemoglobin? d) does bpg increase or decrease the kd of oxygen binding? e) would you expect the bpg levels of someone living at high altitudes to be higher or lower?