Enzymes notes

Introduction to Enzymes

• Definition: Enzymes are large molecules found in living organisms that act as biological catalysts.

• Role: They speed up chemical reactions without being consumed.

Enzyme Function

• Catalysis: Enzymes facilitate almost all chemical reactions in biological cells.

  • Substrates (reactants) are transformed into products after binding to the enzyme.

  • They lower the energy requirement and increase reaction rates.

Types of Enzyme Reactions

• Degradation Reactions: Break down complex substrates into simpler products.

• Synthesis Reactions: Build complex products from simpler substrates.

Composition of Enzymes

• Structure: Mainly proteins made of 100-1000 amino acids.

• Importance of Shape: Enzyme activity heavily relies on its 3D structure, which determines its specific function.

Specificity of Enzymes

• Active Site: The region where substrates bind to the enzyme, crucial for reaction specificity.

• Only substrates with the correct shape fit into the active site, similar to a key fitting into a lock (Lock and Key Model).

Factors Affecting Enzyme Activity

• Denaturation: Enzyme shape changes due to disruptions in bonds, affecting functionality.

  • Causes: High temperature, extreme pH levels.

• Optimum Conditions: Enzymes have specific conditions (temperature and pH) under which they perform best.

  • Most enzymes function best at 30-40°C.

Substrate Concentration

• Effect on Rate: Higher substrate concentrations increase reaction rates up to a saturation point where all active sites are occupied, limiting further increases.

Summary of Enzyme Properties

• Enzymes are found in all living cells, are made of proteins, are biological catalysts, speed up reactions, and are unchanged post-reaction.

Visual Models & Activities

• Diagrams illustrate processes and mechanisms of enzymes at work.

• Activities include true/false statements to test understanding of enzyme properties.