9 Digestion Identify the organs in the 3.3.3 Digestion and absorption 8.4 digestive system Students can make a model of the Describe the functions of the During digestion, large biological human digestive system using alimentary canal molecules are hydrolysed to modelling clay and identify the Identify the enzymes involved smaller molecules that can be different parts. Definitions of key in chemical digestion absorbed across cell membranes. terms can be covered using a card Describe the role and location sort and revisited through a game of each enzyme Digestion in mammals of: of taboo. Chemical digestion of carbohydrates, lipids and proteins carbohydrates by amylases and • can be summarised in turn and membrane-bound disaccharidases recorded in the form of a table. lipids by lipase, including the • Various animations and video clips action of bile salts are available on YouTube to proteins by endopeptidases, • illustrate chemical digestion. exopeptidases and dipeptidases 10 Practical: Investigating chemical Objectives can be chosen 3.3.3 Digestion and absorption PS 1.1 Solve problems set in 8.4 digestion depending on the emphasis of the practical contexts practical lesson: Students could design and carry PS 1.2 Apply scientific out investigations into the effect of Identify independent, knowledge to practical a pH or bile salts on the rate of dependent and control contexts reaction catalysed by a digestive variables enzyme. Give students a list of Design an investigation on the PS 2.2 Present data in equipment available to use and rate of a reaction catalysed by appropriate ways the title of the investigation. a digestive enzyme Templates can be used to help Apply knowledge on chemical PS 2.4 Identify variables structure the design of the digestion to form a including those that must investigation for weaker students. hypothesis and conclusion be controlled Present data collected accurately in tabular form 11 Absorption Identify adaptations of the 3.3.3 Digestion and absorption 8.4 alimentary canal for efficient Products of digestion could be absorption Mechanisms for the absorption of recalled from the previous lesson. Explain how products of the products of digestion by cells Methods of transport from digestion are absorbed from lining the ileum of mammals, to chapter 6 could also be revisited. the lumen of the alimentary include: Absorption of monosaccharides,
9 Digestion Students can make a model of the human digestive system using modelling clay and identify the different parts. Definitions of key terms can be covered using a card sort and revisited through a game of taboo. Chemical digestion of carbohydrates, lipids and proteins can be summarised in turn and recorded in the form of a table. Various animations and video clips are available on YouTube to illustrate chemical digestion. Identify the organs in the digestive system Describe the functions of the alimentary canal Identify the enzymes involved in chemical digestion Describe the role and location of each enzyme 3.3.3 Digestion and absorption During digestion, large biological molecules are hydrolysed to smaller molecules that can be absorbed across cell membranes. Digestion in mammals of: • carbohydrates by amylases and membrane-bound disaccharidases • lipids by lipase, including the action of bile salts • proteins by endopeptidases, exopeptidases and dipeptidases 8.4 10 Practical: Investigating chemical digestion Students could design and carry out investigations into the effect of a pH or bile salts on the rate of reaction catalysed by a digestive enzyme. Give students a list of equipment available to use and the title of the investigation. Templates can be used to help structure the design of the investigation for weaker students. Objectives can be chosen depending on the emphasis of the practical lesson: Identify independent, dependent and control variables Design an investigation on the rate of a reaction catalysed by a digestive enzyme Apply knowledge on chemical digestion to form a hypothesis and conclusion Present data collected accurately in tabular form 3.3.3 Digestion and absorption PS 1.1 Solve problems set in practical contexts PS 1.2 Apply scientific knowledge to practical contexts PS 2.2 Present data in appropriate ways PS 2.4 Identify variables including those that must be controlled 8.4 11 Absorption Products of digestion could be recalled from the previous lesson. Methods of transport from chapter 6 could also be revisited. Absorption of monosaccharides, Identify adaptations of the alimentary canal for efficient absorption Explain how products of digestion are absorbed from the lumen of the alimentary 3.3.3 Digestion and absorption Mechanisms for the absorption of the products of digestion by cells lining the ileum of mammals, to include: 8.4