Biology A-Level
lock and key
What lock and key means in Biology A-Level, as defined for AQA.
Definition of lock and key
Check what you remember
Read the wording for your board, then hide it and explain lock and key in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: AQA
An older model in which the active site is a rigid shape that exactly matches the substrate.
Topics that use lock and key
- Many proteins are enzymes (AQA A-Level)
Related terms
- activation energy
- active site
- competitive inhibition
- conformational change
- denaturation
- enzyme specificity
- enzyme-substrate complex
- induced fit
Using lock and key in the exam
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