CORE: Creative thinkers Enzymes & Proteins L/O: To what enzymes are and how they are affected by different conditions. Success Criteria: A* - Suggest how activation energies are influenced by enzymes A – Link enzyme functions to the digestive system B – Explain how the lock and key theory works C – State what enzymes are and what they do Starter Recap: Answer the question: “What is a chemical reaction and in what ways can we speed them up?” CORE: Creative thinkers

Enzymes = a biological catalyst Catalyst = something that can speed up a reaction without being changed or used up in the reaction

Enzyme: The Facts! Enzymes are all proteins All proteins are made of chains of amino acids and these chains fold up to give the unique shapes Every enzyme has a unique shape that fits onto a substrate at the active site Enzymes only every catalyse one reaction Enzymes catalyse protein synthesis and respiration

The lock and Key theory

Why is shape important? Each enzyme has a different shape Within the shape is the active site Only one type of substrate fits into the active site (like a lock and key) What happens to the substrate after it fits into the active site?

Why is shape important? Draw a cartoon story board of the action of an enzyme of its substrate Add a step by step of what happens Label the following: Active site Substrate Product Enzyme-substrate complex Enzyme-product complex Extension: What will happen if the active site changes shape?

Self Assess! Once the substrate is attached to the active site it is turned into the 2 products

Self Assess! Once the substrate is attached to the active site it is turned into the 2 products

Self Assess! Once the substrate is attached to the active site it is turned into the 2 products

Self Assess! Once the substrate is attached to the active site it is turned into the 2 products

Self Assess! Once the substrate is attached to the active site it is turned into the 2 products

Step-by-Step Self assess Shape of the enzyme’s active site is complimentary to the shape of one particular substrate. The two bind together to form an enzyme-substrate complex. The reaction between them take place rapidly. The products are released from the enzyme’s active site. The enzyme remains unchanged after the reaction

True or False

Where do Enzymes Work? Many enzymes work inside body cells but some enzymes work outside body cells. The digestive enzymes are produced by specialised cells in glands and are then secreted into the gut where they come into contact with food molecules.

What do Digestive Enzymes do? These digestive enzymes catalyse the breakdown of large insoluble food molecules into small soluble molecules that can be absorbed into the blood and transported to other cells in our body

Enzymes in Digestion Recap! Label the parts of the digestive system and what enzymes are found there/ what they do

What are the enzymes and how do they work? http://www.youtube.com/watch?v=Uzl6M1YlU3w

What are the enzymes and how do they work? Peer assess http://www.youtube.com/watch?v=Uzl6M1YlU3w Large insoluble food Enzyme Produced by Starch Amylase (a carbohydrase) Salivary glands, pancreas & small intestines Protein Protease Stomach, pancreas & small intestines Fats (lipids) Lipase Pancreas & small intestines Small soluble product sugars Amino acids Glycerol & fatty acids

Key Enzymes to know… Starch Maltose Amylase Proteins Amino Acids Salivary Glands Pancreas Small intestine Starch Maltose Amylase Stomach Pancreas Small intestines Proteins Amino Acids Protease Pancreas Small intestines Fats Fatty Acid + Glycerol Lipase

Quick Check What is a catalyst? Write a definition of an enzyme. What is the name of the theory that explains how enzymes work What happens in the small intestine? Where do we find amylase? What does protease do? What does lipase break down fats into? What is the optimum temperature of most enzymes? Why have I written “most” in the previous question?

What is the activation energy? Chemical reactions take place when particles collide with enough energy. The amount of energy required to start a reaction is called the activation energy. Enzymes lower the amount of activation energy required, so the reaction can proceed at a greater rate.

What is the activation energy? Different reactions have different activation energies. Enzymes LOWER the activation energy for a reaction to occur reaction (time) energy (kJ) Ea without enzyme Ea with enzyme

What have you learnt? Success Criteria: A* - Suggest how activation energies are influenced by enzymes A – Link enzyme functions to the digestive system B – Explain how the lock and key theory works C – State what enzymes are and what they do Complete the quiz to see how much you have learnt! Then peer assess when teacher goes over the answers 10 min

What have I learnt? Success Criteria: A* - Suggest how activation energies are influenced by enzymes A – Link enzyme functions to the digestive system B – Explain how the lock and key theory works C – State what enzymes are and what they do What have I learnt? In your books give yourself a grade and explain how you have got that grade, and what you have to do to get a higher grade. A* - 5 min