A-LEVEL BIOLOGY AQA NOTES
many proteins are enzymes
Enzymes
- Enzymes are biological catalysts that speeds up the rate of reaction and remains unchanged and reusable at the end of the reaction.
- They lower the activation energy of the reaction.
- The lock and key model proposed that each substrate is a key that only fits a specific lock or enzyme. The alternative induced fit model has been proposed (below)
- The specificity of enzymes is due to the tertiary structure of its active site, allowing complementary binding to substrates.
- Enzymes catalyse both intracellular and extracellular reactions that determine structures and functions from cellular to whole organism level.
- Factors affecting enzyme activity include:
