Quick story · start here
Why does increasing substrate eventually produce diminishing increases in the modeled enzyme reaction rate?
Build the conceptual model first, then test the same idea through the linked scientific representation or tool.
Scene
See the scene
Build the picture before the terminology.
At low substrate concentration, adding substrate strongly increases the modeled initial reaction rate because many enzyme molecules are available to form enzyme-substrate complexes. As substrate becomes abundant, a larger fraction of catalytic sites is occupied and the rate approaches a limiting value rather than increasing without bound.