AP Biology / Unit 3: Cellular Energetics
3.2 Environmental Impacts on Enzyme Function
Notes
- Temperature and pH: each enzyme has an optimum; too far causes denaturation.
- Substrate concentration: rate rises then levels off (saturation).
- Competitive inhibitors bind the active site; more substrate can overcome them.
- Noncompetitive (allosteric) inhibitors bind elsewhere and change the shape.
Practice
Adding much more substrate overcomes which inhibitor?
It outcompetes for the active site.
Above its optimum temperature, an enzyme's rate drops because:
Bonds holding its shape break.
A molecule that binds away from the active site and changes its shape is:
Allosteric site.
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