Biology GCSE
Optimum pH
What Optimum pH means in Biology GCSE, as defined for AQA.
Definitions of Optimum pH
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Reference: AQA
The pH at which an enzyme works best, differing between enzymes such as pepsin in acidic stomach conditions and intestinal enzymes in alkaline conditions.
The pH close to which lipase works best, which bile helps produce by neutralising stomach acid so conditions are alkaline.
The pH at which amylase works fastest, with the rate decreasing at pH values further from it.
The pH giving the shortest time, identified by comparing end-point times across pH values.
Topics that use Optimum pH
- The human digestive system (AQA GCSE)
Related terms
- Absorption and transport
- active site
- Active site and substrate binding
- Amylase
- Anabolic and catabolic reactions
- Apparatus and measurement skills
- Benedict’s test for reducing sugars
- Biological catalysts
Using Optimum pH in the exam
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