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A SPACE TO EXPERIMENT

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01 / ENZYME ACTIVITY

Find the limit.

As substrate increases, an enzyme-catalysed reaction approaches a maximum rate. What happens if you add more enzyme instead?

Try this: double the enzyme amount

Compare 50% with 100% at the same substrate concentration. The rate doubles in this model because there are twice as many active sites. The substrate concentration at half the maximum rate stays at 20 units.

REACTION RATE60.0 relative units
050100150020406080100Rate (relative units)Substrate concentration (relative units)
Your enzyme amount100% referenceUpper dotted line: maximum rate
The curve is flattening as active sites fill.

At 100% enzyme, the model’s maximum rate is 100 units. At 20 substrate units, the rate is exactly half that maximum.

A steady-state Michaelis–Menten illustration: v = Vmax × S / (20 + S). Temperature, pH and enzyme properties are fixed; no inhibition or substrate depletion is modelled. Values are illustrative, not laboratory measurements.

Now turn that observation into an explanation.

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Keep the science in view.

These simplified models explain specific relationships. Read the assumptions beside each experiment and connect your observations with the underlying Biology.

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