Study Notes
Enzymes are biological catalysts that speed up chemical reactions in living organisms without being consumed in the process.
- Enzyme — a protein that acts as a catalyst in biological reactions.
Example: Amylase breaks down starch into sugars. - Active Site — the specific region of an enzyme where the substrate binds.
Example: The active site of sucrase binds to sucrose to catalyze its breakdown. - Substrate — the substance on which an enzyme acts.
Example: Lactose is the substrate for the enzyme lactase. - Denaturation — the process where an enzyme loses its functional shape.
Example: High temperatures can denature enzymes, rendering them inactive.
Exam Tips
Key Definitions to Remember
- Enzyme: A protein that speeds up chemical reactions.
- Active Site: The part of an enzyme where the substrate binds.
- Substrate: The molecule upon which an enzyme acts.
- Denaturation: Loss of an enzyme's functional shape.
Common Confusions
- Enzymes are not consumed in reactions — they can be reused.
- Denaturation is not the same as digestion; it refers to structural changes.
Typical Exam Questions
- What is the role of enzymes in biological reactions? Enzymes act as catalysts to speed up reactions without being consumed.
- How does temperature affect enzyme activity? High temperatures can denature enzymes, reducing their activity.
- What happens at the active site of an enzyme? The substrate binds to the active site, allowing the enzyme to catalyze the reaction.
What Examiners Usually Test
- Understanding of enzyme function and specificity.
- Effects of temperature and pH on enzyme activity.
- Ability to explain enzyme-substrate interactions.