Enzymes

• What are enzymes?


  Protein molecules that catalyse specific reactions
• Why are enzymes described as specific?


  Each enzyme only catalyses a specific reaction
• Describe the function of amylase.


  To break down starch into glucose
• Where is amylase produced?


  Salivary glands, pancreas, and small intestine
• Describe the function of proteases.


  To break down proteins into amino acids
• Where are proteases produced?


  Stomach, pancreas, and small intestine
• Describe the function of lipases.


  To break down lipids into fatty acids and glycerol
• Where are lipases produced?


  Pancreas and small intestine
• What are two factors that affect the rate of enzyme activity?

  Temperature and pH
• What does denatured mean in the context of enzymes?


  The shape of an enzyme's active site is changed
• Describe the effect of temperature on enzyme activity.


  As temperature increases, the rate of reaction increases until it reaches the optimum, then it decreases
• What happens to enzyme activity above the optimum temperature?


  Enzyme activity decreases
• Why do different digestive enzymes have different optimum pH levels?


  Different parts of the digestive system have very different pHs
• What is the pH of the stomach?


  Strongly acidic
• What is the pH in the small intestine?


  Close to neutral