Answer
The Po2 is the is the primary factor that determines how much oxygen binds to hemoglobin
Work Step by Step
Po2 (po2) is the partial pressure of oxygen. Terminology/ abbreviations used to designate partial pressure of oxygen varies: PO2 (Po2) means the partial pressure of oxygen in an environment; PAO2/pAO2 is used to designate the partial pressure (pp) of oxygen in alveoli; the partial pressure of oxygen in arterial blood is often written PaO2