Enzymes and digestion

• Digestive enzymes


  Break down big molecules
• Carbohydrases


  Convert carbohydrates into simple sugars
• Carbohydrases


  • Starch
• Proteases


  Convert proteins into amino acids
• Proteases

  • Made in the stomach and small intestine
• Lipases


  Convert lipids into glycerol and fatty acids
• Lipases


  • Made in the pancreas and small intestine
• The body makes good use of the products of digestion. They can be used to make new molecules like proteins and fats.
• Bile

  Neutralises the stomach acid and emulsifies fats
• Bile


  • Produced in the liver, stored in the gallbladder, released into the small intestine
  • Makes the pH alkaline so enzymes in the small intestine can work properly
  • Breaks fats into smaller droplets to increase the surface area for lipase enzymes
• Make sure you know the examples of amylase, protease and lipase, and the reactions that they catalyse.
• Bile is a product of the liver. Describe and explain its role in digestion
• Enzymes

  Catalyse the breakdown of food
• Parts of the digestive system

  • Liver
  • Salivary glands
  • Esophagus
  • Tongue
  • Stomach
  • Small intestine
  • Large intestine
  • Rectum
  • Pancreas
• Digestion

  1. Produces enzymes

  2. Breaks down food

  3. Absorbs nutrients into the blood
• The small intestine is where the digested food is absorbed into the blood
• The large intestine is where the waste (mainly indigestible food) is stored before being eliminated
• The pancreas produces enzymes and hormones to aid digestion
• The stomach has a pH of 2
• The liver produces bile which aids digestion
• The salivary glands produce saliva which contains enzymes to start digestion