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BUILD A PROCESS

Build a catalytic cycle

Follow an enzyme from substrate encounter to reuse.

Build a process

Use the up and down buttons to build the sequence, then check your reasoning. Some biological events overlap; follow the simplified pathway described here.

  1. 1
    Enzyme is available again
  2. 2
    Products form and leave
  3. 3
    Transition state is stabilised
  4. 4
    Enzyme–substrate complex forms
  5. 5
    Substrate encounters the active site
Read the complete pathway
  1. Substrate encounters the active site. Recognition depends on compatible interactions.
  2. Enzyme–substrate complex forms. Binding can induce changes in molecular shape.
  3. Transition state is stabilised. Catalysis lowers the activation-energy barrier.
  4. Products form and leave. Products interact differently from the substrate.
  5. Enzyme is available again. The catalyst is regenerated.

Explain what you observed

Does an enzyme change equilibrium?

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Your study notes

Take the next step

Connect this activity with your lesson notes and chapter practice.

Read a related learning guide →Practise Enzymes →Open the student notes folder ↗

Concepts and sources

Curriculum connections: 6.1, 6.2. Selected concepts.

Read the supporting source ↗PMDC curriculum ↗

Questions and explanations are original teaching material; these are not official exam questions.

Keep exploring Enzymes

Model

Enzyme saturation

Change substrate and enzyme amounts to discover saturation.

Model

Temperature and pH

Explore how conditions alter an illustrative enzyme profile.

Model

Competitive or noncompetitive?

Change substrate and inhibitor strength to compare rate curves.