hard · Enhanced ACT science
In an experiment on enzyme activity, the rate of a reaction (in arbitrary units) was measured as substrate concentration increased while enzyme amount was held constant:
| Substrate (mM) | Rate |
| :--- | :--- |
| 1 | 10 |
| 2 | 18 |
| 4 | 30 |
| 8 | 40 |
| 16 | 45 |
| 32 | 46 |
Which conclusion is BEST supported by the data?
- Rate increases in direct proportion to substrate concentration across the entire range tested.
- Rate decreases once substrate concentration exceeds 8 mM, indicating substrate inhibition.
- Rate rises steeply at low substrate levels but levels off at high levels, approaching a maximum.
- Doubling the substrate always doubles the rate, so no maximum rate exists.
Sign up free to see the explanation and track your rank →
More Enhanced ACT science practice
- An experimenter tests the effect of different light waveleng… — In this experimental desig
- At any given temperature, the catalyst increases the reaction rate by what factor?
- What is the relationship?
- Which species has a higher population at Year 5?
- Which soil type retains the LEAST amount of water?
- What is the pressure when the volume is 2.0 L?
- If water has a density of 1.00 g/cm³, which liquid will sink in water?
- As the frequency of the waves increases, the wavelength: