This lesson describes the role of the hypothalamus and the mechanisms of thermoregulation that maintain the body in dynamic equilibrium during exercise. The PowerPoint has been designed to cover point 7.12 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification. Students were introduced to homeostasis at GCSE and this lesson has been written to build on that knowledge and to add the key detail needed at this level. Focusing on the three main parts of a homeostatic control system, the students will learn about the role of the internal and peripheral thermoreceptors, the thermoregulatory centre in the hypothalamus and the range of effectors which bring about the responses to restore optimum levels. The following responses are covered in this lesson: Vasodilation Increased sweating Body hairs In each case, time is taken to challenge students on their ability to make links to related topics such as the arterioles involved in the redistribution of blood and the high specific latent heat of vaporisation of water.

This fully-resourced lesson describes the structure and general properties of slow and fast skeletal muscle fibres. The detailed PowerPoint and accompanying resources are the second in a series of 2 lessons that cover the content detailed in point 6.3 of the AQA A-level Biology specification and due to the obvious links, this lesson also challenges the students on their knowledge of respiration, cell structures and biological molecules like glycogen and haemoglobin The following structure and properties are covered over the course of this lesson: Reliance on the aerobic or anaerobic pathways to generate ATP Resistance to fatigue mitochondrial density capillary density myoglobin content (and colour) fibre diameter phosphocreatine content glycogen content A wide variety of tasks are used to cover this content and include knowledge recall and application of knowledge exam-style questions with fully-displayed mark schemes as well as quick quiz competitions to maintain motivation and engagement. This lesson has been specifically planned to tie in with the previous lesson in topic 6.3, titled “Contraction of skeletal muscles”, and this lesson has been uploaded for free

This fully-resourced lesson introduces bacteriostatic and bactericidal antibiotics and describes their differences, focusing on their modes of action. The engaging PowerPoint and accompanying resources have been designed to cover point 6.14 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification but also makes continual links to earlier lessons in topic 6 as well as related topics from the previous year such as protein synthesis from topic 2 The lesson begins by challenging the students to use their knowledge of the previous topic 6 lessons to identify the suffixes cidal and static. Students will learn that when the prefix is added, these form the full names of two types of antibiotics. Their understanding of terminology is tested further as they have to recognise that Polymyxin B is an example of a bactericidal antibiotic as its actions would result in the death of the bacterial cell. Tetracycline is used as the example of a bacteriostatic antibiotic and students will discover that its prevention of the binding of tRNA that inhibits protein synthesis and this reduction and stopping of growth and reproduction is synonymous with these drugs. Students are challenged on their knowledge of translation and will also be given time for a class discussion to understand that these antibiotics encourage the body’s immune system to overcome the pathogen in natural, active immunity. The final part of the lesson uses a quick quiz competition and a series of exam-style questions to ensure that students can recognise the different antibiotics from descriptions.

This fully-resourced lesson describes the development of the humoral and cell-mediated immune responses. The detailed PowerPoint and accompanying resources have been designed to cover points 6.7 (ii) & (iii) as detailed in the Edexcel A-level Biology B specification and includes descriptions of the roles of antigen-presenting cells, T helper cells, cytokines, T killer cells, B cells, clonal selection and plasma cells. Antigen presentation was introduced at the end of the previous lesson so the task at the start of this lesson challenges students to recognise the name of this process and then they have to spot the errors in the passage that describes the details of this event. This reminds them that contact between the APC and T lymphocytes is necessary to elicit a response which they will come to recognise as the cell-mediated response. A series of quick quiz rounds reveals key terms in a memorable way and one that is introduced is helper T cells. Time is then taken to describe the importance of cell signalling for an effective response and students will learn how the release of chemicals by these cells activates other aspects of the response. The role of the killer T cells and their production of cytotoxins is also described before an exam-style question is used to check on their understanding at this point of the lesson. This leads into the section of the lesson that deals with the humoral response and students will understand how this involves the antibodies that are produced by the plasma cells that are the result of clonal selection and expansion. The T and B memory cells are also introduced so that students can understand how they are retained in the body even after the pathogen has been overcome and will play a critical role in the development of immunity. This prepares the students for the next lesson about the role of these memory cells in the secondary immune response.

This fully-resourced lesson describes the role of memory cells in the secondary immune response. The PowerPoint and accompanying resources have been designed to cover specification point 6.7 (iv) of the Edexcel A-level Biology B specification but also contains a detailed description of the structure and function of antibodies and therefore covers this part of 6.7 (ii) As memory B cells differentiate into plasma cells that produce antibodies when a specific antigen is re-encountered, it was decided to link the immune responses and antibodies together in one lesson. The lesson begins by checking on the students incoming knowledge to ensure that they recognise that B cells differentiate into plasma cells and memory cells. This was introduced in a previous lesson on the specific immune response and students must be confident in their understanding if the development of immunity is to be understood. A couple of quick quiz competitions are then used to introduce key terms so that the structure of antibodies in terms of polypeptide chains, variable and constant regions and hinge regions are met. Time is taken to focus on the variable region and to explain how the specificity of this for a particular antigen allows neutralisation and agglutination to take place. The remainder of the lesson focuses on the differences between the primary and secondary immune responses and a series of exam-style questions will enable students to understand that the quicker production of a greater concentration of these antibodies in the secondary response is due to the retention of memory cells.

This fully-resourced lesson describes how vaccinations are used to control disease and how immunity can be natural, artifical, active and passive. The engaging PowerPoint and accompanying resources have been designed to cover points 6.7 (v) & (vi) of the Edexcel A-level Biology B specification and there is also a description and discussion on the development of herd immunity. The previous lesson finished with a series of exam questions where students observed differences between the primary and secondary immune responses so the start of this lesson uses an imaginary game of TOP TRUMPS to challenge them on the depth of their understanding. This will act to remind them that a larger concentration of antibodies is produced in a quicker time in the secondary response. The importance of antibodies and the production of memory cells for the development of immunity is emphasised and this will be continually referenced as the lesson progresses. The students will learn that this response of the body to a pathogen that has entered the body through natural processes is natural active immunity. Moving forwards, time is taken to look at vaccinations as an example of artificial active immunity. Another series of questions focusing on the MMR vaccine will challenge the students to explain how the deliberate exposure to antigenic material activates the immune response and leads to the retention of memory cells. A quick quiz competition is used to introduce the variety of forms that the antigenic material can take along with examples of diseases that are vaccinated against using these methods. The eradication of smallpox is used to describe the concept of herd immunity and the students are given time to consider the scientific questions and concerns that arise when the use of this pathway is a possible option for a government. The remainder of the lesson looks at the different forms of passive immunity and describes the drawbacks in terms of the need for a full response if a pathogen is re-encountered.

This lesson describes the mode of actions of macrophages, neutrophils and lymphocytes. The engaging PowerPoint and accompanying resource have been primarily designed to cover point 6.7 (i) of the Edexcel A-level Biology B specification but includes an introduction to antigen-presentation so that the students are prepared for upcoming lessons on the cell-mediated and humoral responses. At the start of the lesson, the students are challenged to recall that cytosis is a suffix associated with transport mechanisms and this introduces phagocytosis as a form of endocytosis which takes in pathogens and foreign particles. This emphasis on key terminology runs throughout the course of the lesson and students are encouraged to consider how the start or end of a word can be used to determine meaning. The process of phagocytosis is then split into 5 key steps and time is taken to discuss the role of opsonins as well as the fusion of lysosomes and the release of lysozymes. A series of application questions are used to challenge the students on their ability to make links to related topics including an understanding of how the hydrolysis of the peptidoglycan wall of a bacteria results in lysis. Students will be able to distinguish between neutrophils and monocytes from a diagram and at this point, the role of macrophages and dendritic cells as antigen-presenting cells is described so that it can be used in the next lesson. The lesson concludes with an introduction to lymphocytes so that initial links between phagocytosis and the specific immune responses are made.

This lesson describes how the Hardy-Weinberg equation can identify changes in allele frequency that can be the result of mutation and natural selection. The detailed PowerPoint and accompanying resources have been designed to cover points 4.20 (i) & (ii) of the Edexcel International A-level Biology specification The lesson begins with a focus on the equation to ensure that the students understand the meaning of each of the terms. The recessive condition, cystic fibrosis, is used as an example so that students can start to apply their knowledge and assess whether they understand which genotypes go with which term. Moving forwards, a step-by-step guide is used to show students how to answer a question. Tips are given during the guide so that common misconceptions and mistakes are addressed immediately and then students are given the opportunity to apply their knowledge to a set of 3 questions, which have been differentiated so that all abilities are able to access the work and be challenged The rest of the lesson focuses on describing how the mutations which create the variation needed for natural selection to occur can be given as reasons for any change in allele frequency. 2 quick quiz competitions are used to introduce MRSA and then to get the students to recognise that they can use this abbreviation to remind them to use mutation, reproduce, selection (and survive) and allele in their descriptions of evolution through natural selection. The main task of the lesson challenges the students to form a description that explains how this strain of bacteria developed resistance to methicillin to enable them to see the principles of natural selection. This can then be used when describing how the anatomy of the modern-day giraffe has evolved over time.

This fully-resourced lesson provides examples of anatomical, behavioural and physiological adaptations of organisms to their environment. The engaging and detailed PowerPoint and accompanying resources have been designed to cover point 4.19 in unit 2 of the Edexcel International A-level Biology specification and also describes the concept of a niche and makes continual links to related topics such as natural selection A quick quiz competition at the start of the lesson introduces the different types of adaptation and a series of tasks are used to ensure that the students can distinguish between anatomical, behavioural and physiological adaptations. The Marram grass is used to test their understanding further, before a step by step guide describes how the lignified cells prevent a loss of turgidity. Moving forwards, the students are challenged to explain how the other adaptations of this grass help it to survive in its environment. A series of exam-style questions on the Mangrove family will challenge them to make links to other topics such as osmosis and the mark schemes are displayed to allow them to assess their understanding. The final part of the lesson focuses on the adaptations of the anteater but this time links are made to the upcoming topic of taxonomy so that students are prepared for this lesson on species and classification hierarchy.

This lesson describes biodiversity and explains how it can be calculated within a species, a habitat and how it can be compared between habitats. The detailed PowerPoint and accompanying resources have been designed to cover points 4.16, 4.17 & 4.18 in unit 2 of the Edexcel International A-level Biology specification and the meaning of endemism is also explained. A quiz competition called BIOLOGICAL TERMINOLOGY SNAP runs over the course of the lesson and this will engage the students whilst challenging them to recognise key terms from their definitions. This quiz will introduce species, population, biodiversity, endemic, heterozygote and natural selection and each of these terms is put into context once introduced. Once biodiversity has been revealed, the students will learn that they are expected to be able to measure biodiversity within a habitat, within a species and within different habitats so that they can be compared. The rest of the lesson uses step by step guides, discussion points and selected tasks to demonstrate how to determine species richness, the heterozygosity index and an index of diversity. Students are challenged with a range of exam-style questions where they have to apply their knowledge and all mark schemes are displayed and clearly explained within the PowerPoint to allow students to assess their understanding and address any misconceptions if they arise.

This lesson describes the similarities and differences between the structure, position and function of the xylem, phloem and the sclerenchyma fibres. The engaging and detailed PowerPoint and accompanying resources have been designed to cover point 4.5 in unit 2 of the Edexcel International A-level Biology specification. The lessons begins by challenging the students to identify the substances that a plant needs for the cellular reactions, where they are absorbed and where these reactions occur in a plant. The aim of this task is to get the students to recognise that water and mineral ions are absorbed in the roots and needed in the leaves whilst the products of photosynthesis are in the leaves and need to be used all over the plant. Students will be reminded that the xylem and phloem are part of the vascular system responsible for transporting these substances and then the rest of the lesson focuses on linking structure to function. A range of tasks which include discussion points, exam-style questions and quick quiz rounds are used to describe how lignification results in the xylem as a hollow tube of xylem cells to allow water to move as a complete column. They will also learn that the narrow diameter of this vessel allows capillary action to move water molecules up the sides of the vessel. The same process is used to enable students to understand how the structures of the companion cells allows assimilates to be loaded before being moved to the sieve tube elements through the plasmodesmata. The final part of the lesson introduces the sclerenchyma tissue as part of the vascular bundle and along with the structure and function, the students will observe where this tissue is found in the stem in comparison to the xylem and phloem. It is estimated that it will take in excess of 2 hours of A-level teaching time to cover the detail which has been written into this lesson

This lesson describes the relationship between the structure and function of the polysaccharides, starch and cellulose. The detailed PowerPoint and accompanying resource have been designed to cover point 4.3 of the Edexcel International A-level Biology specification and includes a focus on the role of the hydrogen bonds between the beta-glucose molecules in the formation of cellulose microfibrils. The structure of amylose and amylopectin was described during a lesson in topic 1, so the start of this lesson challenges the students on their recall of these details. They have to complete a comparison table for these two polysaccharides by identifying the monomer and type of glycosidic bonds that are found in each of the structures. Time is taken to explain how the greater resistance to digestion of amylose means that this carbohydrate is important for plant energy storage whereas the multiple chain ends in the branched amylopectin means that this polysaccharide can be hydrolysed quickly when energy is needed. The rest of the lesson describes the structure of cellulose and focuses on the link between the structure and the need for this polysaccharide to support the plant cell as well as the whole plant. Students will see how every other beta glucose monomer is rotated by 180 degrees and will learn that hydrogen bonds form between these molecules on the same chain as well as between adjacent chains in a cellulose microfibril. The lesson concludes with a quick quiz competition where the students have to compete to open a safe using a combination made up of key values associated with glycogen, starch and cellulose.

This lesson describes the structure and ultrastructure of plant cells to allow students to compare this structure against animal cell structure. The detailed PowerPoint and accompanying resources have been designed to cover points 4.1 (i) & (ii) in unit 2 of the Edexcel International A-level Biology specification and also describes the functions of the cell wall, chloroplast, amyloplast, vacuole, tonoplast, plasmodesmata, pits and middle lamella The lesson begins with a task called REVERSE GUESS WHO which will challenge the students to recognise a particular organelle from a description of its function. This will remind students that plant cells are eukaryotic and therefore contain a cell-surface membrane, a nucleus (+ nucleolus), a mitochondria, a Golgi apparatus, ribosomes and rough and smooth endoplasmic reticulum like the animal cells. Moving forwards, the next part of the lesson focuses on the relationship between the structure and function of the vacuole, chloroplast, plasmodesmata and cellulose cell wall. When considering the vacuole, key structures such as the tonoplast are described as well as critical functions including the maintenance of turgor pressure. A detailed knowledge of the structure of the chloroplast at this early stage of their A-level studies will increase the likelihood of a clear understanding of photosynthesis when covered in topic 5. For this reason, time is taken to consider the light-dependent and light-independent reactions and to explain how these stages are linked. Students will learn that chloroplasts and amyloplasts can contain stores of starch so an opportunity is taken to challenge them on their knowledge of this polysaccharide as it was covered in topic 1. The final task challenges them to recognise descriptions of the cell wall, chloroplast, amyloplasts, vacuole, tonoplast and plasmodesmata which will leave 2 remaining which describe the pits and middle lamella.

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.

This lesson describes how individuals may develop immunity, focusing on the different types that are active, passive, natural and artificial. The engaging PowerPoint and accompanying resources have been designed to cover point 6.1 of the Edexcel International A-level Biology specification and there is also a description and discussion of herd immunity to increase the relevance to the current epidemic with COVID-19. The lesson begins with a series of exam-style questions which challenge the students to demonstrate and apply their understanding of the immune response as covered in the previous lessons in this topic. In answering and assessing their answers to these questions, the students will recognise the differences between the primary and secondary immune responses and then a discussion period is included to encourage them to consider how the production of a larger concentration of antibodies in a quicker time is achieved. The importance of antibodies and the production of memory cells for the development of immunity is emphasised and this is continually referenced as the lesson progresses. The students will learn that this response of the body to a pathogen that has entered the body through natural processes is natural active immunity. Moving forwards, time is taken to look at vaccinations as an example of artificial active immunity. Another series of questions focusing on the MMR vaccine will challenge the students to explain how the deliberate exposure to antigenic material activates the immune response and leads to the retention of memory cells. A quick quiz competition is used to introduce the variety of forms that the antigenic material can take along with examples of diseases that are vaccinated against using these methods. The eradication of smallpox is used to describe the concept of herd immunity and the students are given time to consider the scientific questions and concerns that arise when the use of this pathway is a possible option for a government. The remainder of the lesson looks at the different forms of passive immunity and describes the drawbacks in terms of the need for a full response if a pathogen is re-encountered.

This fully-resourced lesson describes the differences between the roles of the B cells and T cells in the body’s immune response. The PowerPoint and accompanying resources have been designed to cover points 6.9 & 6.10 in unit 4 of the Edexcel International A-level Biology specification and includes descriptions of the role of the antigens and the production of antibodies by plasma (effector) cells In the previous lesson on the non-specific responses, the students were introduced to macrophages and dendritic cells as antigen-presenting cells and the start of this lesson challenges their recall and understanding of this process. Time is taken to discuss how the contact between these cells and lymphocytes is critical for the initiation of the body’s (specific) immune response. Moving forwards, a quick quiz competition is used to introduce the names of the different T cells that result from differentiation. Their specific roles are described including an emphasis on the importance of the release of cytokines in cell signalling to activate other immune system cells. T memory cells are also introduced so that students can understand their role in immunological memory and active immunity as described in an upcoming lesson. The next part of the lesson focuses on the B cells and describes how clonal selection and clonal expansion results in the formation of memory B cells and effector cells. A series of understanding and application questions are then used to introduce the structure of antibodies and to explain how the complementary shape of the variable region allows the antigen-antibody complex to be formed. The lesson concludes by emphasising that the pathogen will be overcome as a result of the combination of the actions of phagocytes, T killer cells and the antibodies released by the effector cells

This lesson describes the non-specific responses of the body to infection which include inflammation, lysozyme action, interferon and phagocytosis. The detailed PowerPoint and accompanying resources have been primarily designed to cover the content of point 6.8 of the Edexcel International A-level Biology specification but key details such as antigen-presentation are also introduced to prepare students for upcoming lessons on the immune response (6.9 & 6.10). At the start of the lesson, the students are challenged to recall that cytosis is a suffix associated with transport mechanisms and this introduces phagocytosis as a form of endocytosis which takes in pathogens and foreign particles. This emphasis on key terminology runs throughout the course of the lesson and students are encouraged to consider how the start or end of a word can be used to determine meaning. The process of phagocytosis is then split into 5 key steps and time is taken to discuss the role of opsonins as well as the fusion of lysosomes and the release of lysozymes. A series of application questions are used to challenge the students on their ability to make links to related topics including an understanding of how the hydrolysis of the peptidoglycan wall of a bacteria results in lysis. Students will be able to distinguish between neutrophils and monocytes from a diagram and at this point, the role of macrophages and dendritic cells as antigen-presenting cells is described so that it can be used in the next lesson. The importance of cell signalling for an effective immune response is discussed and the rest of the lesson focuses on the release of two chemicals - interferons and histamine. During the interferon section, references are made to a previous lesson on HIV structure and action so students can understand how the release of these signalling proteins helps neighbouring cells to heighten their anti-viral defences. A step by step guide is used to describe the release of histamine in the inflammatory response and the final task challenges students to use this support to form a detailed answer regarding the steps in inflammation.

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 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 5.4 (ii) of the Edexcel International A-level Biology 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