Diet and Digestion Lesson Objectives

DD1 Diet and deficiencies Recall that balanced diet includes carbohydrate, protein, lipid, vitamins, minerals, water and dietary fibre Recall sources and functions of carbohydrate, protein, lipid (fats and oils) in the diet, Vitamins A, C and D, and the mineral ions Ca and Fe, water and fibre (roughage).

DD2 Biological molecules and food tests Test the following food groups: Benedicts (glucose),Iodine (starch), Biuret (protein), alcohol emulsion (fat) Describe structure of carbohydrates, proteins and lipids as large molecules made up from smaller basic units: starch and glycogen from simple sugar; protein from amino acids; lipid from fatty acids and glycerol

DD3 The Mouth and Amylase Recognise the structures of the human alimentary canal (gut) Describe functions of mouth (incl teeth/saliva), oesophagus, Explain how food is moved through the gut by peristalsis Explain digestion of starch to glucose by amylase and maltase, explain active sites – theory of enzyme action

DD4 The Stomach and Pepsin Describe functions of stomach, Describe the digestion of proteins to amino acids by proteases Define ingestion, digestion, absorption, assimilation and egestion

DD5 Bile salts and Lipase Describe digestion of lipids to fatty acids and glycerol by lipase Carry out a practical demonstrating the effect of Bile salts on digestion of fat Explain the role of the pancreas Describe how the functioning of enzymes can be affected by changes in temperature State bile is produced by liver, stored in the gall bladder, Describe the role of bile in neutralising stomach acid and emulsifying lipids

DD6 The Model Gut and Small Intestine Draw a villus, and explain how villi help absorption in S.I. Explain the role of the small intestine, large intestine Define : diffusion, osmosis and active transport

DD7 Literacy task Travel supermarket or Vitamin deficiencies

DD8 Enzymes and pH (triple only) Key assessment Explain how the functioning of enzymes can be affected by changes in pH