This concise lesson presentation (20 slides) guides students through the effect of changing pressure on the position of the equilibrium. The key skill to this topic involves recalling the rule of increasing pressure and being able to recognise how many moles are on each side of the reaction. For this reason, time is taken to remind the students of the meaning of the mole numbers in a reaction and working through an example together so they can see which side will be favoured. The final part of the lesson involves a game called “The PRESSURE is on” where students are in a race against the clock to balance an equation and then work out which way the equilibrium will shift when either the pressure is increased or decreased. This lesson has been written for GCSE students.

This lesson has been written for GCSE students, with the main focus being to introduce reversible reactions, show them how to represent them in both word and symbol equations, and to look at some well-known examples. Related topics such as the position of the equilibrium and endothermic and exothermic reactions are briefly mentioned so that students can recognise the potential crossover between topics. Some time is taken during the lesson to challenge the students to write a balanced symbol equation having been given a description of a reversible reaction. This task is differentiated with an assistance sheet so that all are able to access the learning. There are a number of these progress checks in this short lesson so that students can assess their understanding on a regular basis. Students will learn that the reaction in one direction will be exothermic and why this matters in terms of temperature and the equilibrium position. Increasing pressure and the number of moles is also discussed and an answer explained.

This is a concise, fast-paced lesson which guides students through the critical skills needed to calculate the atom economy of a chemical reaction. It has been designed for GCSE students and focuses on the calculation as well as interpreting the final value. In order to calculate the mass of the desired product and other products, students have to be able to calculate the relative formula mass - therefore time is taken to revisit these skills and worked examples are used with this and the actual calculations to enable the students to visualise how they should set their work out. The lesson finishes with some progress check questions where students are challenged to state which of four chemical reactions has the highest atom economy. This lesson could be taught in combination with the percentage yield topic and an accompanying lesson on that calculation is available on this site.

This lesson uses the example of the genetic engineering of bacteria to produce insulin to walk students through the steps involved in this process. It has been written for GCSE students and therefore includes the detail required at this level, such as the involvement of restriction enzymes and the sticky ends that their cut produces. The lesson begins by challenging students to recognise that insulin is being described by a series of clues. Some further details of this hormone are recalled to test their previous knowledge of the endocrine system and also to lead into the genetic engineering of bacteria to make this protein. Moving forwards, time is taken to go through the details of plasmids and how they act as vectors as well as the enzymes, restriction and ligase. The main task of the lesson uses a series of descriptions to go through the steps involved in the process. Words or phrases are missing from each description so students have to use the terms they’ve encountered in this lesson as well as their prior knowledge to complete the step. Discussion-provoking questions are added to encourage the students to consider why certain parts of the process occur. The lesson concludes by the consideration of other organisms which have been genetically engineered as well as some of the risks of the process, which students are asked to complete for homework. As detailed above, this lesson has been designed for GCSE students but could be used with students taking A-level Biology, who are struggling to understand the detail found at this level and need to revisit the foundations.

This lesson describes and explains how increasing the temperature affects the rate of an enzyme-controlled reaction. The PowerPoint and the accompanying resource have been designed to cover the second part of point 1.4.2 of the AQA A-level Biology specification and ties in directly with the previous lesson on the properties of enzymes and their mechanism of action. The lesson begins by challenging the students to recognise optimum as a key term from its 6 synonyms that are shown on the board. Time is taken to ensure that the students understand that the optimum temperature is the temperature at which the most enzyme-product complexes are produced per second and therefore the temperature at which the rate of an enzyme-controlled reaction works at its maximum. The optimum temperatures of DNA polymerase in humans and in a thermophilic bacteria and RUBISCO in a tomato plant are used to demonstrate how different enzymes have different optimum temperatures and the roles of the latter two in the PCR and photosynthesis are briefly described to prepare students for these future lessons. Moving forwards, the rest of the lesson focuses on enzyme activity at temperatures below the optimum and at temperatures above the optimum. Students will understand that increasing the temperature increases the kinetic energy of the enzyme and substrate molecules, and this increases the likelihood of successful collisions and the production of enzyme-substrate and enzyme-product complexes. When considering the effect of increasing the temperature above the optimum, continual references are made to the previous lesson and the control of the shape of the active site by the tertiary structure. Students will be able to describe how the hydrogen and ionic bonds in the tertiary structure are broken by the vibrations associated with higher temperatures and result in an active site that is no longer complementary to the substrate. Key terminology such as denaturation is used throughout. Please note that this lesson has been designed specifically to explain the relationship between the change in temperature and the rate of reaction and not the practical skills that would be covered in a core practical lesson

This lesson describes and explains how increasing the concentration of inhibitors affects the rate of an enzyme-controlled reaction. The PowerPoint and accompanying resource are the last in a series of 5 lessons which cover the content detailed in point 1.4.2 of the AQA A-level Biology specification and describes the effect of both competitive and non-competitive inhibitors. The lesson begins with a made up round of the quiz show POINTLESS called “Biology opposites” and this will get the students to recognise that inhibition is the opposite of stimulation. This introduces inhibitors as substances that reduce the rate of a reaction and students are challenged to use their general knowledge of enzymes to identify that inhibitors prevent the formation of the enzyme-substrate complex. Moving forwards, a quick quiz competition generates the abbreviation EIC (representing enzyme-inhibitor complex) and this introduces competitive inhibitors as substances that occupy the active site. The students are asked to apply their knowledge to a new situation to work out that these inhibitors have a similar shape to the enzyme’s substrate molecule. A series of exam-style questions are used throughout the lesson and at this point, the students are challenged to work out that an increase in the substrate concentration would reduce the effect of a fixed concentration of a reversible competitive inhibitor. The rest of the lesson focuses on non-competitive inhibitors and time is taken to ensure that key details such as the disruption of the tertiary structure is understood and biological examples are used to increase the relevance. Again, students will learn that increasing the concentration of the inhibitor results in a greater inhibition and a reduced rate of reaction but that increasing the substrate concentration cannot reduce the effect as was observed with competitive inhibitors.

This fully-resourced lesson describes how enzymes function intracellularly and extracellularly and explains their mode of action. The engaging PowerPoint and accompanying resources have been designed to cover points 3.1 (a, b & c) and considers the details of Fischer’s lock and key hypothesis and Koshland’s induced-fit model and explains how an enzyme’s specificity is related to their 3D structure and enables them to act as biological catalysts. The lesson has been planned to tie in with topic 2.3, and to challenge the students on their knowledge of protein structure and globular proteins. This prior knowledge is tested through a series of exam-style questions along with current understanding and mark schemes are included in the PowerPoint so that students can assess their answers. Students will learn that enzymes are large globular proteins which contain an active site that consists of a small number of amino acids. Emil Fischer’s lock and key hypothesis is introduced to enable students to recognise that their specificity is the result of an active site that is complementary in shape to a single type of substrate. Time is taken to discuss key details such as the control of the shape of the active site by the tertiary structure of the protein. The induced-fit model is described so students can understand how the enzyme-susbtrate complex is stabilised and then students are challenged to order the sequence of events in an enzyme-controlled reaction. The lesson finishes with a focus on ATP synthase and DNA polymerase so that students are aware of these important intracellular enzymes when learning about the details of respiration and DNA replication before they are challenged on their knowledge of carbohydrates, lipids and proteins from topics 1.2 - 1.4 as they have to recognise some extracellular digestive enzymes from descriptions of their biological molecule substrates.

This lesson describes and explains the effect of an increasing temperature on the rate of an enzyme-catalysed reaction. The PowerPoint and the accompanying resource are part of the 1st lesson in a series of 4 which cover the content detailed in point 3.2 (a) of the CIE A-level Biology specification and this lesson has been specifically planned to tie in with the lesson in 3.1 where the properties of enzymes and their mechanism of action were introduced. The lesson begins by challenging the students to recognise optimum as a key term from its 6 synonyms that are shown on the board. Time is taken to ensure that the students understand that the optimum temperature is the temperature at which the most enzyme-product complexes are produced per second and therefore the temperature at which the rate of an enzyme-controlled reaction works at its maximum. The optimum temperatures of DNA polymerase in humans and in a thermophilic bacteria and RUBISCO in a tomato plant are used to demonstrate how different enzymes have different optimum temperatures and the roles of the latter two in the PCR and photosynthesis are briefly described to prepare students for these lessons in topics 19 and 13. Moving forwards, the rest of the lesson focuses on enzyme activity at temperatures below the optimum and at temperatures above the optimum. Students will understand that increasing the temperature increases the kinetic energy of the enzyme and substrate molecules, and this increases the likelihood of successful collisions and the production of enzyme-substrate and enzyme-product complexes. When considering the effect of increasing the temperature above the optimum, continual references are made to the previous lesson and the control of the shape of the active site by the tertiary structure. Students will be able to describe how the hydrogen and ionic bonds in the tertiary structure are broken by the vibrations associated with higher temperatures and are challenged to complete the graph to show how the rate of reaction decreases to 0 when the enzyme has denatured. Please note that this lesson has been designed specifically to explain the relationship between the change in temperature and the rate of reaction and not the practical skills that would be covered in a core practical lesson

This lesson describes and explains how increasing the concentration of inhibitors affects the rate of an enzyme-catalysed reaction. The PowerPoint and accompanying resource are the last in a series of 4 lessons which cover the content detailed in point 3.2 (a) of the CIE A-level Biology specification but this lesson also covers point 3.2 [c] as competitive and non-competitive inhibitors are introduced and their differing effects on enzyme activity described and explained. The lesson begins with a made up round of the quiz show POINTLESS called “Biology opposites” and this allows students to recognise that inhibition is the opposite of stimulation. This introduces inhibitors as substances that reduce the rate of a reaction and students are challenged to use their general knowledge of enzymes to identify that inhibitors prevent the formation of the enzyme-substrate complex. Moving forwards, a quick quiz competition generates the abbreviation EIC (representing enzyme-inhibitor complex) and this introduces competitive inhibitors as substances that occupy the active site. The students are asked to apply their knowledge to a new situation to work out that these inhibitors must have a similar shape to the enzyme’s substrate molecule. A series of exam-style questions are used throughout the lesson and at this point, the students are challenged to work out that an increase in the substrate concentration would reduce the effect of a fixed concentration of a reversible competitive inhibitor. The rest of the lesson focuses on non-competitive inhibitors and time is taken to ensure that key details such as the disruption of the tertiary structure is understood and biological examples are used to increase the relevance. Again, students will learn that increasing the concentration of the inhibitor results in a greater inhibition and a reduced rate of reaction but that increasing the substrate concentration cannot reduce the effect as was observed with competitive inhibitors.

This lesson describes how enzymes can be immobilised in calcium alginate and compares their activity against enzymes that are free in solution. The PowerPoint and the accompanying resources have been designed to cover point 3.2 (d) of the CIE A-level Biology specification. The lesson has been planned to challenge the students on their ability to apply knowledge to a potentially unfamiliar situation. A series of exam-style questions which include “suggest” and “describe and explain” questions are used throughout the lesson and these will allow the students to recognise the advantages and disadvantages of a particular method. Although the alginate method is the only one referenced in this specification point, the adsorption and covalent bonding methods are introduced and then briefly analysed to allow students to understand that a matrix doesn’t involve these bonds which could disrupt the active site. The remainder of the lesson introduces some actual examples of the use of immobilised enzymes with the aim of increasing the relevance. Please note that this lesson has been written to explain the effect of immobilisation on enzyme activity. The practical element of carrying out the investigation is described in a separate lesson.