Digestive System

• Benedict's solution is used to test for sugars (lipids).
• Iodine solution is used to test for starch (fats).
• Biuret solution is used to test for proteins.
• The large intestine absorbs water from the food.
• Carbohydrases breaks down carbohydrates into simple sugars.
• Amylase breaks down starch into glucose.
• Protease breaks down proteins into amino acids.
• Lipase breaks down lipids into fatty acids and glycerol.
• Amylase is made in the salivary glands, pancrease and the small intestine.
• Protease are made in the stomach, pancrease and the small intestine.
• Lipase is made in the pancreas and the small intestine.
• The liver produces bile which helps to emulsify fats so that they can be broken down by enzymes.
• Bile neutralises stomach acid and emulsifies fats.
• The pancrease produces protease, amylase and lipase enzymes.
• The rectum is where the faeces are stored before being excreted through the anus.
• The gall bladder is where bile is stored before released.
• If a food sample has sugar (lipids) the colour in the test tube should change from blue to green, yellow or brick red.
• If the food sample contains starch the colour of the solution should change from browny-orange to black or blue-black.
• If the food sample changes from blue to pink or purple.