This lesson describes how the mechanisms involved in the selective reabsorption of solutes in the proximal convoluted tubule. The PowerPoint and accompanying resource have been designed to cover the first part of specification point 9.9 (iii) of the Edexcel A-level Biology B specification and builds on the knowledge gained in the previous lessons on the structure of the nephron and ultrafiltration. The lesson begins by challenging the students to recall the substances that are found in the glomerular filtrate so that each of them can be considered over the course of the rest of the lesson. Moving forwards, the first of the numerous discussion points which are included in the lesson is used to get students to predict the component of the filtrate which won’t be found in the urine when they are presented with pie charts from each of these situations. Upon learning that glucose is 100% reabsorbed, along with most of the ions and some of the water, the rest of the lesson focuses on describing the relationship between the structure of the PCT and the function of selective reabsorption. Again, this section begins by encouraging the students to discuss and to predict which structures they would expect to find in a section of the kidney if the function is to reabsorb. They are given the chance to see the structure (as shown in the cover image) before each feature is broken down to explain its importance. Time is taken to look at the role of the cotransporter proteins to explain how this allows glucose, along with sodium ions, to be reabsorbed from the lumen of the PCT into the epithelial cells. The final part of the lesson focuses on urea and how the concentration of this substance increases along the tubule as a result of the reabsorption of some of the water.

This detailed lesson describes the gross and microscopic structure of the mammalian kidney. The engaging PowerPoint and accompanying resource have been designed to cover point 9.9 (i) of the Edexcel A-level Biology B specification. The lesson was designed to tie in with the other lessons in topic 9.9 on ultrafiltration, selective reabsorption and the control of mammalian plasma concentration and a common theme runs throughout to allow students to build their knowledge gradually and develop a deep understanding of this organ. Students will come to recognise the renal cortex and renal medulla as the two regions of the kidney and learn the parts of the nephron which are found in each of these regions. Time is taken to look at the vascular supply of this organ and specifically to explain how the renal artery divides into the afferent arterioles which carry blood towards the glomerulus and the efferent arterioles which carry the blood away. The main task of the lesson challenges the students to relate structure to function. Having been introduced to the names of each of the parts of the nephron, they have to use the details of the structures found at these parts to match the function. For example, they have to make the connection between the microvilli in the PCT as a sign that this part is involved in selective reabsorption.

This fully-resourced lesson describes the effects of enzyme and substrate concentration on the rate of enzyme-catalysed reactions. The PowerPoint and accompanying resources are the third in a series of 4 lessons which cover the details of point 3.2 (a) of the CIE A-level Biology specification. The first part of the lesson describes how an increase in substrate concentration will affect the rate of reaction when a fixed concentration of enzyme is used. Time is taken to introduce limiting factors and students will be challenged to identify substrate concentration as the limiting factor before the maximum rate is attained and then they are given discussion time to identify the possible factors after this point. A series of exam-style questions are used throughout the lesson and the mark schemes are displayed to allow the students to assess their understanding and for any misconceptions to be immediately addressed. Moving forwards, the students have to use their knowledge of substrate concentration to construct a graph to represent the relationship between enzyme concentration and rate of reaction and they have to explain the different sections of the graph and identify the limiting factors. The final section of the lesson describes how the availability of enzymes is controlled in living organisms. Students will come to recognise that this availability is the result of enzyme synthesis and enzyme degradation and a series of tasks will introduce the details of transcription and translation and therefore prepare them for the lessons in topic 6. Please note that this lesson explains the Biology behind the effect of concentration on enzyme-catalysed reactions and not the methodology involved in carrying out such an investigation as this is covered in a core practical lesson.

This lesson explains the effects of temperature increases on enzyme activity and describes how to calculate the temperature coefficient. The PowerPoint and the accompanying resource are part of the second lesson in a series of 3, which cover the content detailed in point 2.1.4 (d) [i] of the OCR A-level Biology A specification and this lesson has been specifically planned to tie in with an earlier lesson covering 2.1.4 (a, b & c) where the roles and mechanism of action of enzymes 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 modules 6 and 5. Moving forwards, the next part 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. The final part of the lesson introduces the Q10 temperature coefficient and students are challenged to apply this formula to calculate the value for a chemical reaction and a metabolic reaction to determine that enzyme-catalysed reactions have higher rates of reaction Please note that this lesson has been designed specifically to explain the relationship between the change in temperature and the rate of enzyme activity in a reaction and not the practical skills that is part of a lesson covering specification point 2.1.4 (d) [ii]

This lesson describes how to use and manipulate the magnification formula to calculate the magnification or the actual size in a range of units. The PowerPoint and accompanying resources have been designed to cover point 2.1.1 (e) of the OCR A-level Biology A specification and contains a number of quiz rounds as part of the competition that runs throughout all of the module 2.1.1 lessons The students are likely to have met the magnification formula at GCSE so this lesson has been written to build on that knowledge and to support them with more difficult questions when they have to calculate actual size without directly being given the magnification. A step by step guide is used to walk the students through the methodology and useful tips are provided. Students could be asked to calculate the actual size in millimetres, micrometres, nanometres or picometres so time is taken to ensure that they can convert between one and another.

This engaging lesson explains why coenzymes, cofactors and prosthetic groups are needed in some enzyme-controlled reactions. The PowerPoint and accompanying resource have been primarily designed to cover point 2.1.4 (e) of the OCR A-level Biology specification but can also be used as a revision lesson for the roles of ions as was covered back in module 2.1.2. The lesson begins with an introduction of the description of a cofactor and students will learn that some are permanently bound to the enzyme whilst others only form temporary associations. A quick quiz competition runs over the course of the lesson and is used to introduce prosthetic groups, mineral ion cofactors and organic coenzymes and zinc ions with carbonic anhydrase, chloride ions with amylase and NAD are used as examples of each type. The lesson has been planned to make links to related topics such as cations, anions, transport of carbon dioxide and respiration which will test students on their prior knowledge as well as prepare them for these topics in modules 3 and 5.

This lesson describes the light-dependent reactions of photosynthesis, focusing on the link to the light-independent reactions. The detailed PowerPoint and accompanying resources have been designed to cover the details included in point 5.7 of the Edexcel A-level Biology specification and therefore describes how light energy is trapped by exciting electrons in chlorophyll and the role of these electrons in generating ATP, reducing NADP in photophosphorylation and producing oxygen through photolysis of water. This is a topic which students tend to find difficult so this lesson has been intricately planned to walk them through each of the key reactions in the light-dependent stage. Time is taken to describe the roles of the major protein complexes that are embedded in the thylakoid membrane and this includes the two photosystems, the proton pump and ATP synthase. A series of exam-style questions have been written that link to other biological topics in this course such as cell structure and membrane transport as well as application questions to challenge them to apply their understanding. Some of these resources have been differentiated to allow students of differing abilities to access the work and to be pushed at the same time. Students will learn that there are two pathways that the electron can take from PSI and at the completion of the two tasks which describe each of these pathways, they will understand how ATP is generated in non-cyclic and cyclic fashion. The final task of the lesson asks them to compare these two forms of photophosphorylation to check that they understand when photolysis is involved and reduced NADP is formed. Due to the detail included in this lesson, it is estimated that it will take in excess of 2.5 hours of allocated A-level teaching time to complete

This lesson describes how the products of the light-independent reactions of photosynthesis are used by plants, animals and other organisms. The engaging and detailed PowerPoint and accompanying resources have been primarily designed to cover point 5.8 (ii) of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification concerning the uses of GP and GALP but as the lesson makes continual references to biological molecules, it can act as a revision tool for a lot of the content of topic 1 and 2. The previous lesson described the light-independent reactions and this lesson builds on that understanding to demonstrate how the intermediates of the cycle, GP and GALP, are used. The start of the lesson challenges the students to identify two errors in a diagram of the cycle so that they can recall that most of the GALP molecules are used in the regeneration of ribulose bisphosphate. A quiz version of Pointless runs throughout the lesson and this is used to challenge the students to recall a biological molecule from its description. Once each molecule has been revealed, time is taken to go through the details of the formation and synthesis of this molecule from GALP or from GP in the case of fatty and amino acids. The following molecules are considered in detail during this lesson: glucose (and fructose and galactose) sucrose starch and cellulose glycerol and fatty acids amino acids nucleic acids A range of activities are used to challenge their prior knowledge of these molecules and mark schemes are always displayed for the exam-style questions to allow the students to assess their understanding. As detailed above, this lesson has been specifically written to tie in with the earlier lessons in this topic on the structure of the chloroplast and the light-dependent and light-independent reactions of photosynthesis

This fully-resourced lesson describes how Mycobacterium tuberculosis and Human Immunodeficiency virus infect human cells. The PowerPoint and accompanying resources have been designed to cover point 6.6 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification and ties in directly with the previous lesson where the structure of bacteria and viruses were compared. The lesson begins by ensuring that students recognise that TB is caused by the infection of a species of bacteria known as Mycobacterium tuberculosis and they will challenged to use their knowledge of scientific classification to recall that this pathogen is found in the mycobacteria genus. At this point, the students are told that the cell walls of this genus contain mycolic acids and later in the lesson they will have to work out that this specialist feature enables this pathogen to survive phagocytosis. A series of exam-style questions will challenge their knowledge of the respiratory and immune systems as they can understand how the bacterium travels to the alveoli where it is engulfed by a macrophage. Key terms like granuloma and necrosis are introduced and the sequence of events that occur following the formation of this aggregate of cells is described. The structure of viruses was covered during the previous lesson, so this next part of the lesson starts by challenging the students to recall the capsid, genetic material in the form of viral RNA and the lipid envelope. At this point, the students are introduced to gp120, the glycoprotein which is exposed on the surface of the lipid envelope, as this structure is critical for the entry of the virus into host cells. Students will annotate a basic diagram of HIV with these four structures which also has gp41 labelled. A quick quiz competition introduces the names of the enzymes found inside the capsid Moving forwards, the main task of this part of the lesson describes how HIV binds to the helper T cells, injects its capsid and integrates its DNA into the host’s genome in order to replicate to form virus particles (virions). Students are guided through the formation of a detailed answer about the mechanism of HIV and have to input key terms and structures where information is missing. Students will learn that the increase in the number of virus particles and a decrease in helper T cells and other immune cells results in infections like TB and by opportunistic pathogens and that this stage is recognised as AIDS

This fully-resourced lesson describes how isolation reduces gene flow between populations which leads to allopatric and sympatric speciation. The engaging PowerPoint and accompanying resources have been designed to cover point 5.24 of unit 4 of the Edexcel International A-level Biology specification and uses a range of real life examples to increase the relevance and to deepen student understanding The lesson begins by using the example of a hinny, which is the hybrid offspring of a horse and a donkey, to challenge students to recall the biological classification of a species. Moving forwards, students are introduced to the idea of speciation and the key components of this process, such as isolation and selection pressures, are covered and discussed in detail. Understanding and prior knowledge checks are included throughout the lesson to allow the students to not only assess their progress against the current topic but also to make links to earlier topics in the specification. Time is taken to look at the details of allopatric speciation and how the different mutations that arise in the isolated populations and genetic drift will lead to genetic changes. The example of allopatric speciation in wrasse fish because of the isthmus of Panama is used to allow the students to visualise this process. The final part of the lesson considers sympatric speciation and again a wide variety of tasks are used to enable a deep understanding to be developed.

This fully-resourced lesson describes the relationship between the structure of the chloroplast and its role in the overall reaction of photosynthesis. The detailed PowerPoint and accompanying resources have been designed to cover points 5.5 & 5.9 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification and provide a thorough introduction to the light-dependent and light-independent reactions which are covered in the next 3 lessons. Students will have some knowledge of photosynthesis from GCSE and were introduced to the ultrastructure of eukaryotic cells in topics 3 and 4 so this lesson has been written to test and to build on that knowledge. A version of the quiz show POINTLESS runs throughout the lesson and this maintains engagement whilst challenging the students to recall the parts of the chloroplast based on a description which is related to their function. The following structures are covered in this lesson: double membrane thylakoids (grana) stroma intergranal lamellae starch grains chloroplast DNA and ribosomes Once each structure has been recalled (or introduced) , a range of activities are used to ensure that key details are understood. As the main focus of the lesson is the reaction of photosynthesis, extra time is taken to introduce the details of the light-dependent and light-independent reactions that take place in the grana and stroma respectively. This includes descriptions of the role of the thylakoid membranes in the light-dependent reactions and the importance of ATP and reduced NADP for the reduction of GP to GALP in the Calvin cycle of the light-independent reactions. Links to other related topics are also made throughout and this is exemplified by the final task of the lesson where students are challenged on their recall of the structure, properties and function of starch (as originally covered in topic 1) As described above, this lesson has been specifically planned to prepare students for the upcoming lessons that cover the details of specification points 5.7 & 5.8 (i) and (ii).

This lesson describes the key structural features of viruses and challenges the students to compare them against those of a bacteria as covered in topic 3. The PowerPoint and accompanying resource have primarily been designed to cover point 6.5 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification but can be used a revision tool for point 3.4 as students need to recall the structures of a prokaryotic cell. Details of the COVID-19 epidemic are included in the lesson to increase relevance and to help students to understand this biological topic in greater depth. They will understand that a virus’ lack of cell structures results in an non-cellular classification and the fact that it is unable to reproduce without a host is one of the additional reasons that renders it as non-living. The main focus of the lesson is the nucleic acid, the capsid and the attachment proteins that are present in these microorganisms and time is taken to explain how these structures are involved in the infection of a host cell. The lipid membrane is also introduced and links are made to the previous lessons on eukaryotic cells. The final section of the lesson challenges the students to recognise the following prokaryotic cell structures from their descriptions: plasmid pili capsule cell wall flagellum circular DNA ribosomes mesosomes This lesson has been specifically planned to link to the next lesson which covers point 6.6 on the infection of human cells by Mycobacterium tuberculosis and human immunodeficiency virus

This fully-resourced lesson describes the the overall reaction of photosynthesis that takes place in the grana and stroma of the chloroplast. The detailed PowerPoint and accompanying resources have been designed to cover points 5.1 & 5.5 in unit 4 of the Edexcel International A-level Biology specification and also describes the relationship between the structure and role of the chloroplast Students will have some knowledge of photosynthesis from iGCSE and were introduced to the ultrastructure of eukaryotic cells in topics 3 and 4 so this lesson has been written to test and to build on that knowledge. A version of the quiz show POINTLESS runs throughout the lesson and this maintains engagement whilst challenging the students to recall the parts of the chloroplast based on a description which is related to their function. The following structures are covered in this lesson: double membrane thylakoids (grana) stroma intergranal lamellae starch grains chloroplast DNA and ribosomes Once each structure has been recalled (or introduced) , a range of activities are used to ensure that key details are understood. As the main focus of the lesson is the reaction of photosynthesis, extra time is taken to introduce the details of the light-dependent and light-independent reactions that take place in the grana and stroma respectively. This includes descriptions of the role of the thylakoid membranes in the light-dependent reactions and the importance of ATP and reduced NADP for the reduction of GP to GALP in the Calvin cycle of the light-independent reactions. Links to other related topics are also made throughout and this is exemplified by the final task of the lesson where students are challenged on their recall of the structure, properties and function of starch (as originally covered in topic 1) As described above, this lesson has been specifically planned to prepare students for the upcoming lessons that cover the details of specification points 5.3 & 5.4 (i) and (ii).

This lesson describes how the hydrolysis of ATP supplies energy for biological processes and how the phosphorylation of ADP requires energy. The PowerPoint has been designed to cover point 5.2 in unit 4 of the Edexcel International A-level Biology specification and also describes how the ATP that is made in the light-dependent stage of photosynthesis, is needed in the light-independent stage. The start of the lesson focuses on the structure of this energy currency and challenges the students to use their knowledge of nucleotides and specifically RNA nucleotides to recognise the components of ATP. As a result, they will learn that this molecule consists of adenine, ribose and three phosphate groups. In order to release the stored energy, ATP must be broken down and students will be given time to discuss which reaction will be involved as well as the products of this reaction. Time is taken to describe how the hydrolysis of ATP can be coupled to energy-requiring reactions within cells and the examples of skeletal muscle contraction are used as this is covered in greater detail in topic 7. The final part of the lesson considers how ATP is formed when ADP is phosphorylated and students will learn that this occurs in the mitochondria and chloroplast during aerobic respiration and photosynthesis respectively, so that it ties in with the upcoming lessons in topic 5 and 7.

This lesson describes the light-independent reactions of photosynthesis as the reduction of carbon dioxide using the products of the light-dependent reactions. The detailed PowerPoint and accompanying resources have been designed to cover point 5.4 (i) of the Edexcel International A-level Biology specification and this means that it describes carbon fixation in the Calvin cycle and the roles of GP, GALP, RuBP and RUBISCO. The lesson begins with an prior knowledge check where the students are challenged to recall the names of structures, substances and reactions from the light-dependent stage in order to reveal the abbreviations of the main 3 substances in the light-independent stage. This immediately introduces RuBP, GP and GALP and students are then shown how these substances fit into the cycle. The main section of the lesson focuses on the three phases of the Calvin cycle and time is taken to explore the key details of each phase and includes: The role of RUBISCO in carbon fixation The role of the products of the light-dependent stage, ATP and reduced NADP, in the reduction of GP to GALP The use of the majority of the GALP in the regeneration of RuBP . A step-by-step guide, with selected questions for the class to consider together, is used to show how 6 turns of the cycle are needed to form the GALP that will then be used to synthesise 1 molecule of glucose. A series of exam-style questions are included at appropriate points of the lesson and this will introduce limiting factors as well as testing their ability to answer questions about this stage when presented with an unfamiliar scientific investigation. The mark schemes are included in the PowerPoint so students can assess their understanding and any misconceptions are immediately addressed. This lesson has been specifically written to tie in with the previous lessons on the structure of a chloroplast and the light-dependent reactions as well as the upcoming lesson on the products of the light-independent reactions.

This lesson describes the light-dependent reactions of photosynthesis, including cyclic and non-cyclic photophosphorylation. The detailed PowerPoint and accompanying resources have been designed to cover point 5.3 in unit 4 of the Edexcel International A-level Biology specification and therefore this lesson describes how light energy is trapped by exciting electrons in chlorophyll and the role of these electrons in generating ATP, reducing NADP in photophosphorylation and producing oxygen through photolysis of water. This is a topic which students tend to find difficult so this lesson has been intricately planned to walk them through each of the key reactions in the light-dependent stage. Time is taken to describe the roles of the major protein complexes that are embedded in the thylakoid membrane and this includes the two photosystems, the proton pump and ATP synthase. A series of exam-style questions have been written that link to other biological topics in this course such as cell structure and membrane transport as well as application questions to challenge them to apply their understanding. Some of these resources have been differentiated to allow students of differing abilities to access the work and to be pushed at the same time. Students will learn that there are two pathways that the electron can take from PSI and at the completion of the two tasks which describe each of these pathways, they will understand how ATP is generated in non-cyclic and cyclic fashion. The final task of the lesson asks them to compare these two forms of photophosphorylation to check that they understand when photolysis is involved and reduced NADP is formed. Due to the detail included in this lesson, it is estimated that it will take in excess of 2.5 hours of allocated A-level teaching time to complete

This fully-resourced lesson describes how Mycobacterium tuberculosis and human immunodeficiency virus infect human cells and cause symptoms. The PowerPoint and accompanying resources have been designed to cover point 6.6 in unit 4 of the Edexcel International A-level Biology specification and ties in closely with the previous lesson where the structure of bacteria and viruses were compared. The lesson begins by ensuring that students recognise that TB is caused by the infection of a species of bacteria known as Mycobacterium tuberculosis and they will challenged to use their knowledge of scientific classification to recall that this pathogen is found in the mycobacteria genus. At this point, the students are told that the cell walls of this genus contain mycolic acids and later in the lesson they will have to work out that this specialist feature enables this pathogen to survive phagocytosis. A series of exam-style questions will challenge their knowledge of the respiratory and immune systems as they can understand how the bacterium travels to the alveoli where it is engulfed by a macrophage. Key terms like granuloma and necrosis are introduced and the sequence of events that occur following the formation of this aggregate of cells is described. The structure of viruses was covered during the previous lesson, so this next part of the lesson starts by challenging the students to recall the capsid, genetic material in the form of viral RNA and the lipid envelope. At this point, the students are introduced to gp120, the glycoprotein which is exposed on the surface of the lipid envelope, as this structure is critical for the entry of the virus into host cells. Students will annotate a basic diagram of HIV with these four structures which also has gp41 labelled. A quick quiz competition introduces the names of the enzymes found inside the capsid Moving forwards, the main task of this part of the lesson describes how HIV binds to the helper T cells, injects its capsid and integrates its DNA into the host’s genome in order to replicate to form virus particles (virions). Students are guided through the formation of a detailed answer about the mechanism of HIV and have to input key terms and structures where information is missing. Students will learn that the increase in the number of virus particles and a decrease in helper T cells and other immune cells results in infections like TB and by opportunistic pathogens and that this stage is recognised as AIDS

This lesson explains how the polymerase chain reaction (PCR) is used to amplify DNA. The PowerPoint has been designed to cover point 6.17 of the Edexcel International A-level Biology specification. A quick quiz competition is used to introduce the PCR abbreviation before students are encouraged to discuss the identity of the enzyme involved and to recall the action of this enzyme. Students will learn that this reaction involves cyclical heating and cooling to a range of temperatures so the next part of this lesson looks at these particular temperatures so the important parts of each of the steps can be understood. Time is taken to examine the key points in detail, such as the specific DNA polymerase that is used and how it is not denatured at the high temperature as well as the involvement of the primers.