enzymes and digestion

• what do digestive enzymes do?

  • break down big insoluble molecules (starch, proteins and fats) int smaller soluble molecules (sugar, amino acids, glycerol and fatty acids)
• what does amylase do?

  • amylase converts starch - maltose
  • maltase converts maltose - glucose
• what does protease do?

  • protease converts protein - amino acids
• what do lipases do?

  • lipases converts lipids - glycerol and fatty acids
• what does bile do?

  • neutralises stomach acid and emulsifies fats
• How does bile do this?

  • bile produced in the liver - stored in gall bladder before released in small intestine
  • HCL in stomach acid - pH too acidic for enzymes in small intestine to work
  • bile alkaline - neutralises acid- makes conditions alkaline - small intestines enzymes work best at these alkaline conditions
  • bile also emulsifies fats - breaks fat into tiny droplets - much bigger SA of fat for lipase to work on - digestion faster
• how does peristalsis work?

  • muscular tissue at the bottom of alimentary canal - job to squeeze boluses through your gut - otherwise clogged up by old bits of food
  • squeezing action - waves of circular muscle contractions - peristalsis