| What are enzymes | - Biological catalysts
- Speed up an reaction without changing themselves - can be reused
- Globular proteins |
| Conditions that must be satisfied for reaction to take place | - Molecules must collide with sufficient energy to alter arrangement of atoms - activation energy
- The free energy of the products must be less than the substrates |
| Activation energy meaning | - The minimum amount of energy required for reactions to take place |
| Enzymes and activation energy | - Enzymes work by lowering the activation energy level
- This allows reactions to take place at lower temperatures like 37 degrees in the body |
| Enzyme structure
(lock and key) | - The substrate fits into the active site and binds with the enzyme
- The substrate splits into products and leaves active site |
| Enzyme structure
(induced fit) | - Enzymes are very specific and only bond to particular substrates
- Has complementary shape to substrate
- Substrate has to be right shape to fit the active site and has to make the active site change shape in the right way
- Forms enzyme-substrate complexes
- Lowers activation energy |
| Enzyme properties related to their tertiary structure | - The active site's shape is determined by the tertiary structure of proteins
- An altered structure means it wont form an enzyme-substrate complex and so the substrate wont be catalysed |
| How enzyme lowers activation energy (induced fit theory) | - The active site moulds around substrate
- Putting tension on bonds
- Lowering the activation energy |
