Enzymes and digestion

• Why do molecules of starch, protein and fat need to be digested?

  They are too large so they need to be broken down in order for them to then be absorbed
• In which part of the digestive system doe the digestion of lipids occur?

  Small intestine
• In which part of the digestive system does the digestion of starch begin?

  Mouth
• What do we call substances like amylase and protease that speed up chemical reactions?

  Enzymes/Catalysts
• Digestive enzymes are made by different organs in the digestive system
• how does hydrochloric acid help digestion?

  It makes the PH lower for better enzyme activity- enzymes are most effective in acidic conditions
• Where is hydrochloric acid made?

  The stomach
• Amylase breaks starch into…

  sugars
• Lipase breaks down fats into…

  fatty acids and glycerol
• Protease breaks down proteins into…

  amino acids
• Which organs produce amylase enzymes?

  salivary glands, pancreas, small intestine
• Which organs produce lipease enzymes?

  Pancreas, small intestine
• Which organs produce protease enzymes?

  Stomach, small intestine, Pancreas
• Describe the products of digestion that enable molecules to be absorbed into the bloodstream

  Small and soluble
• How do enzymes break down substrates?

  -Substrate binds to the active site

  -Shape of the active site is complimentary to substrate

  (fit together like 2 pieces of a jigsaw)

  -Chemical reaction occurs

  -bonds within the substrate molecule break down to produce smaller molecules

  -products diffuse away from active site
• Salivary amylase

  Enzyme produced by the salivary glands in your mouth that breaks down starches into simpler sugars, starting the digestion process even before food reaches your stomach.
• Pancreatic amylase


  Enzyme produced by the pancreas and released into the small intestine that continues breaking down starches into simpler sugars, which are then absorbed into the bloodstream.