* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download File
G protein–coupled receptor wikipedia , lookup
Metabolic network modelling wikipedia , lookup
Gaseous signaling molecules wikipedia , lookup
Deoxyribozyme wikipedia , lookup
Lipid signaling wikipedia , lookup
Western blot wikipedia , lookup
Nicotinamide adenine dinucleotide wikipedia , lookup
Ultrasensitivity wikipedia , lookup
Specialized pro-resolving mediators wikipedia , lookup
Restriction enzyme wikipedia , lookup
Proteolysis wikipedia , lookup
Biochemistry wikipedia , lookup
Amino acid synthesis wikipedia , lookup
Oxidative phosphorylation wikipedia , lookup
Metalloprotein wikipedia , lookup
Catalytic triad wikipedia , lookup
NADH:ubiquinone oxidoreductase (H+-translocating) wikipedia , lookup
Biosynthesis wikipedia , lookup
Evolution of metal ions in biological systems wikipedia , lookup
Weekly Plan 18 Enzyme action 1 Student book links 2.1.18 2.1.19 2.1.20 Specification links 2.1.3 (a)-(c) Link to GCSE specification Suggested time allowed: Enzymes Digestion Nutrition Four hours Lesson time allocated: Suggested teaching order Weekly learning outcomes Students should be able to: State that enzymes are globular proteins, with a specific tertiary structure, which catalyse metabolic reactions in living organisms. State that enzyme action may be intracellular or extracellular. Describe, with the aid of diagrams, the mechanism of action of enzyme molecules with reference to specificity, active site, lock and key hypothesis, induced-fit hypothesis, enzyme–substrate complex, enzyme–product complex and lowering of activation energy. 1. 2. 3. 4. 5. 6. Enzymes as globular proteins with an active site Enzymes as catalysts and features of catalysts Roles and locations of enzymes Lock and key and induced fit Effect on activation energy Effect of mutations on enzyme structure Key words How science works Enzyme. Tertiary structure. Metabolism. Globular protein. Primary structure. Amino acid. Protein. Secondary structure. Hydrophobic. Hydrophilic. Catalyst. Complementary. Substrate. Active site. Secondary structure. Glycosidic bond. Ester bond. Peptide bond. Respiration. Photosynthesis. Maltose. Glucose. Monomer. ATP. Glycogen. Protease. Extracellular. Intracellular. Metabolism. Endotherm. Optimum temperature. Heterotroph. Mitochondria. Vesicle. Carbohydrate. Lipid. Fatty acid. Glycerol. Endocytosis. Lysosome. Lock and key hypothesis. Induced fit hypothesis. Covalent bond. Activation energy. Hydrolysis. Metabolism. Enzyme–substrate complex. Enzyme–product complex. DNA. Mutation. HSW 1: Using models HSW 3 & 6: Solving scientific problems designing washing powder Learning styles (S = Starter activities, M = Main activities, P = Plenary activities) ICT activities Kinaesthetic Activity Activity M1&M3 Activity P1&P3 Interpersonal Activity S1–S2 Activity M1&M3 Activity P1–P3 Auditory Activity S1–S2 Activity M1&M3 Activity P1–P3 Visual Activity S1–S3 Activity M1–M3 Activity P1&P3 Animation: Enzyme specificity Animation: What is an enzyme? Animation: Enzyme shape Use of Internet for Homework suggestions section © Pearson Education Ltd 2008 This document may have been altered from the original 1 Weekly Plan 18 Suggested starter activities Equipment Teacher notes 1. Make two jellies before the lesson. One with fresh pineapple incorporated and one without. The pineapple jelly doesn’t set. Also make one jelly with tinned pineapple, which does set. Jelly, fresh pineapple, tinned pineapple, bowls. You may also want to try kiwi, mango or papaya. Pineapples and some other fruits contain an enzyme called bromelin that digests the gelatine. Use as basis for discussion. Ask them why the jelly made with tinned pineapple set and why many meat casseroles (e.g. Moroccan cookery) involve cooking the meat slowly with fresh fruit. What does that tell us about the optimum temperature/ heat stability of the enzymes in the fruit? 2. Divide the class into groups with the topics: structure; examples; and applications. Each group speaks for 30 seconds on their topic in relation to enzymes. 3. Demonstrate catalysis using manganese dioxide (catalyst) and hydrogen peroxide: 2H2O2 2H20 + O2. Hydrogen peroxide, boiling tube, manganese dioxide Try this before the lesson and take suitable precautions. Suggested main activities Equipment Teacher notes 1. In groups, carry out an enzyme-controlled reaction. Worksheet: Enzyme-controlled reaction Use this as a context for introducing ideas of enzyme– substrate complex, reactants and products. 2. Distribute diagrams of an enzyme colliding with a substrate through to the products being formed. Students must summarise the stages as a series of bullet points. Diagrams of stages of enzyme action 3. In groups, make models of enzyme action to represent induced fit. Model-making equipment: sponges; card; plastic bottles; bubble wrap; polystyrene etc. Suggested plenary activities Equipment 1. Students must match enzymes with the reactions they catalyse. This is well suited to a card-sort activity. Cards with enzyme names and corresponding reactions 2. Give students a series of statements about enzymes. They must vote whether they are true or false Create set of true/false cards about enzymes 3. Give students a series of cards to play snap with. A snap pair consists of a diagram on one card and a corresponding explanation on the other. Make set of 20 cards as described Teacher notes You should make 10 cards with diagrams and 10 cards with corresponding explanations. © Pearson Education Ltd 2008 This document may have been altered from the original 2 Weekly Plan 18 Homework suggestions Make a study stack about the mechanism of enzyme action. Notes: Enzymes 'study stack' Adopt the role of an enzyme and write a blog, describing what you do during catalysis. Produce a cartoon strip with written commentary of what happens during phagocytosis, providing details of enzyme action. Cross-curriculum links Chemistry – biochemistry of enzymes and kinetic theory Extension ideas Students write a comprehension exercise. The questions should pick out the relevant information from the Wikipedia entry on catalysis. Students design their own biological washing power. Worksheet: Design your own washing powder Potential misconceptions Although the lock and key model is an obvious staging post, ensure that students can distinguish between it and the induced fit model. It is useful to relate the structure of an enzyme and the specificity of the active site back to more general ideas about protein structure. The idea of activation energy is very abstract. Using an explanation involving a transition state is usually most effective. Notes The web links referred to here are some that the author has found personally helpful but are not intended to be a comprehensive list, many other good resources exist. © Pearson Education Ltd 2008 This document may have been altered from the original 3