A 50-year-old man with uncontrolled type 2 diabetes mellitus and peripheral vascular disease complains of leg pain during walking (intermittent claudication). His physician explains that during exercise, his tissues demand more oxygen. This process is facilitated by the Bohr effect, which enhances oxygen unloading from hemoglobin in response to increased metabolic activity. Which of the following best describes how the Bohr effect facilitates oxygen unloading?
