The binding of oxygen to hemoglobin is allosterically regulated by various tropic factors, such as BPG and acidity.

He warmed to his modesty, his unbullying camaraderie and genial absent-mindedness; he was touched, too, by this southerner's affection for a northern city, so heartfelt that he had actually made his home here.

Christmas dinner with all the trimmings

[I]n other words, some Jews thought of Moses as the one who laid down the Law, while others saw him more as a prophet.