A laboratory tests a lipase that breaks down lipids in waste cooking oil. The rate of reaction is measured at five pH values. All other conditions are kept constant.
| pH | Rate of reaction in mmol min−1\mathrm{mmol\,min^{-1}}mmolmin−1 |
|---|---|
| 4 | 0.8 |
| 6 | 3.2 |
| 8 | 5.1 |
| 10 | 2.9 |
| 12 | 0.3 |
Explain which pH value should be chosen to obtain the fastest rate and why the rates are lower at the other pH values.
184 exam-style questions on OCR GCSE Biology 1.2 What happens in cells (and what do cells need)?, covering 1.2.1 Structure of DNA, 1.2.2 Nucleotides and complementary bases, 1.2.3 Protein synthesis, 1.2.4 DNA structure and the proteins made, 1.2.5 Investigating enzymatic reactions, and 1.2.6 Mechanism of enzyme action. Each one has a worked solution and a mark scheme showing where the marks go.