GCSE Biology Enzymes in digestion

1. teeth Salivary glands oesophagus Gall bladder liver Large intestine anus rectum Small intestine pancreas stomach Label this diagram of the DIGESTIVE SYSTEM STARTER More realistic digestive system anatomy

2. LEARNING OUTCOMES Enzymes in digestion ALL Label the anatomy of the digestive system MOST Explain how and why large molecules such as starch, protein and fats are broken down SOME Explain the importance of bile in fat digestion

3. ENZYMES IN DIGESTION Large molecules are insoluble and cannot pass through the walls of the small intestine into the blood Enzymes catalyse the breakdown of large insoluble molecules into small soluble ones These can then be absorbed in to the blood blood vessel blood vessel small intestine semi permeable walls

4. Large molecules to Small ones STARCH … to GLUCOSE PROTEIN … to AMINO ACIDS FATS … to GLYCEROL & FATTY ACIDS Large molecules to Small ones Complete the table on page 9 in your work book using this slide AND reading through page 182 of the text book mouth stomach small intestine Digestion occurs in three places… lipase protease amylase

5. LIPASE Small intestine Alkali pH Acid pH Bile Produced by the liver and stored in the gall bladder

6. ISA effect of bile on lipase Ensure that you are working safely by following the safety advice of your teacher! Lipase works best at alkali pH

7. LEARNING OUTCOMES Enzymes in digestion ALL Label the anatomy of the digestive system MOST Explain how and why large molecules such as starch, protein and fats are broken down SOME Explain the importance of bile in fat digestion