Anatomy ch 4

• Enzymes do the following:

  Increase rate of reaction

  Not changed by reactions

  Lower activation energy required
• Enzymes are located:

  Within cells (DNA polymerase)

  In plasma membrane (lactose)

  Secreted from cells (starch)
• The function of enzyme depends on its shape
• Each enzyme has a 3d shaoe with pockets for enzyme activity sites
• Reactants called substrate fit into activation sites on the enzyme
• Induced fit model is when an enzyme binds to activation site and substrate conforms to it
• In the case of lactose:

  Enzyme lactase holds glucose and galactose and snaps the bond
• Enzyme activity is influenced by:

  Tenperature

  pH

  Concentration of cofactor and coenzyme

  Concentration of substrate (adding more will not speed up the process)
• Inhibitors bind to enzymes and prevent enzymatic catalysis
• Competitive inhibitor resembles substrate and binds to activation site which will change shape of enzyme
• Noncompetitove inhibitor will bind to enzyme and change its shape
• Metabolic pathway series if enzyme reactions, not all reactions are linear