This lesson describes the role of myelination in saltatory conduction. The PowerPoint and accompanying worksheet have been designed to cover point 8.5 of the Edexcel International A-level Biology specification and includes constant references to the earlier lessons on the structure of neurones and the conduction of an action potential along an axon. A wide range of activities have been written into this resource to maintain the motivation of the students whilst ensuring that the detail is covered in depth. Interspersed with the activities are understanding checks and prior knowledge checks to allow the students to not only assess their understanding of the current topic but also challenge themselves to make links to earlier topics such as the movement of ions across membranes and biological molecules. Time at the end of the lesson is also given to future knowledge such as the involvement of autonomic motor neurones in the stimulation of involuntary muscles. Over the course of the lesson, students consider the structure of the myelin sheath and specifically how the insulation is not complete all the way along which leaves gaps known as the nodes of Ranvier which allow the entry and exit of ions. Saltatory conduction tends to be poorly explained by students so time is taken to look at the way that the action potential jumps between the nodes and this is explained further by reference to local currents. The rest of the lesson focuses on the other two factors which are axon diameter and temperature and students are challenged to discover these two by focusing on the vampire squid.

This lesson explains how a nerve impulse (action potential) is conducted along an axon and focuses on the role of the sodium and potassium ions. The PowerPoint and accompanying resources have been designed to cover point 8.4 of the Edexcel International A-level Biology specification and contains detailed descriptions of resting potential, depolarisation, repolarisation, hyperpolarisation and the refractory period. This topic is commonly assessed in the terminal exams so extensive planning ensures that this resource includes a wide range of activities to motivate and engage the students whilst ensuring that the content is covered in the depth of detail that will allow them to have a real understanding. Interspersed within the activities are understanding checks and prior knowledge checks to enable the students to not only assess their progress against the current topic but also to challenge themselves on the links to earlier topics such as methods of movements across cell membranes. There are also a number of quiz competitions which are used to introduce key terms and values in a fun and memorable way and discussion points to encourage the students to consider why a particular process or mechanism occurs. Over the course of the lesson, the students will learn and discover how the movement of ions across the membrane causes the membrane potential to change. They will see how the resting potential is maintained through the use of the sodium/potassium pump and potassium ion leakage. There is a real focus on depolarisation to allow students to understand how generator potentials can combine and if the resulting depolarisation then exceeds the threshold potential, a full depolarisation will occur. At this point in the lesson students will discover how the all or nothing response explains that action potentials have the same magnitude and that instead a stronger stimulus is linked to an increase in the frequency of the transmission. The rest of the lesson challenges the students to apply their knowledge to explain how repolarisation and hyperpolarisation result and to suggest advantages of the refractory period for nerve cells.

This lesson describes the development and spread of antibiotic resistance in bacteria and discusses the difficulties in controlling this spread. The PowerPoint and accompanying worksheet have been designed to cover specification points 6.4 (i & ii) of the Edexcel A-level Biology B specification President Trump’s error ridden speech about antibiotics is used at the beginning of the lesson to remind students that this is a treatment for bacterial infections and not viruses as he stated. Moving forwards, 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 the development of resistance by evolution through natural selection. The main task of the lesson challenges the students to form a description to explain how this strain of bacteria developed resistance to methicillin, making use of the five key terms emphasised above. Moving forwards, there is a focus on the hospital as the common location for MRSA infections and students will recognise that this opportunistic pathogen can infect through open wounds to cause sepsis and potentially death. Figures from infections and deaths in hospitals in the US are used to increase the relevance and students will learn how a MRSA prevention program in VHA facilities includes screening of surgery patients to try to reduce its impact. The lesson concludes with a discussion about other methods that can be used by hospitals and general practitioners to reduce the spread of MRSA and to try to prevent the development of resistance in other strains.

This lesson outlines how bacteria become resistant to antiobiotics and discusses its consequences and the steps taken to reduce its impact. The PowerPoint and accompanying worksheet have been designed to cover specification points 10.2 (b & c) of the CIE A-level Biology specification President Trump’s error ridden speech about antibiotics is used at the beginning of the lesson to remind students that this is a treatment for bacterial infections and not viruses as he stated. Moving forwards, 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 the development of resistance by evolution through natural selection. The main task of the lesson challenges the students to form a description to explain how this strain of bacteria developed resistance to methicillin, making use of the five key terms emphasised above. Moving forwards, there is a focus on the hospital as the common location for MRSA infections and students will recognise that this opportunistic pathogen can infect through open wounds to cause sepsis and potentially death. Figures from infections and deaths in hospitals in the US are used to increase the relevance and students will learn how a MRSA prevention program in VHA facilities includes screening of surgery patients to try to reduce its impact. The lesson concludes with a discussion about other methods that can be used by hospitals and general practitioners to reduce the impact of MRSA and to try to prevent the development of resistance in other strains.

This lesson outlines how penicillin acts on bacteria and why antibiotics do not affect viruses. The PowerPoint and accompanying resources have been designed to cover point 10.2 (a) of the CIE A-level Biology specification and also introduces the concept of bactericidal and bacteriostatic antibiotics, as illustrated by penicillin and tetracycline. The lesson begins with an engaging task, where the students have to identify the surnames of famous scientists from their descriptions to reveal the surname Fleming. This introduces Sir Alexander Fleming as the microbiologist who discovered penicillin in 1928. Time is taken to describe penicillin as a group of antibiotics that contain a beta-lactam ring in their molecular structure. Using this information and their knowledge of bacterial cell structure from topic 1, the students have to complete a passage describing how penicillin inhibits the formation of cross links in cell wall synthesis. A series of exam-style questions are then used to make links to the upcoming topic of antibiotic resistance. The next part of the lesson focuses on the differences between bactericidal and bacteriostatic antibiotics and the students will learn that penicillin is bactericidal as the weakening of the cell wall leads to lysis and death. Tetracycline is used as the example of a bacteriostatic antibiotic and students will discover that it is the prevention of the binding of tRNA that inhibits protein synthesis and that this reduction and prevention of growth and reproduction is synonymous with these antimicrobial agents. Students are challenged on their knowledge of translation and will also be given time for a class discussion to understand that these antibiotics work in tandem the body’s immune system to overcome the pathogen The final part of the lesson explains why antibiotics are ineffective against viruses.

This lesson describes the action of bactericidal and bacteriostatic antibiotics, as illustrated by penicillin and tetracycline. The engaging PowerPoint and accompanying resources have been designed to cover point 6.3 (i) of the Edexcel A-level Biology B specification but it has been specifically planned to make continual links to earlier lessons in topic 6 and to protein synthesis as covered in topic 1 The lesson begins by challenging the students to use their general biological knowledge and any available sources 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. Time is then taken to describe the action of penicillin and students will learn how inhibitors and modified versions of this antibiotic are used to overcome those bacteria who have resistance. 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 these different types of antibiotics from descriptions.

This lesson describes self and non-self antigens and how a failure to distinguish between the two is the mechanism of autoimmune diseases. The PowerPoint and accompanying worksheets have been primarily designed to cover points 11.1 (d & f) of the CIE A-level Biology specification and describe examples of these diseases including myasthenia gravis, but this lesson can also be used to revise the content of the earlier topics as well as the previous lessons in topic 10 & 11 through the range of activities that are included The first part of the lesson focuses on the antigens and explains how the failure of the immune system cells to recognise these molecules on the outside of a cell or organism elicits an immune response. Moving forwards, the students are challenged to recognise diseases from descriptions and then to use the first letters of their names to form the term, autoimmune. In doing so, the students will discover that rheumatoid arthritis, ulcerative colitis, type I diabetes mellitus, multiple sclerosis and myasthenia gravis are all examples of autoimmune diseases. The next part of the lesson focuses on the mechanism of these diseases where the immune system cells do not recognise the antigens (self-antigens) on the outside of the healthy cells, and therefore treats them as foreign antigens, resulting in the production of autoantibodies against proteins on these healthy cells and tissues. Key details of the autoimmune diseases stated above and lupus are described and links to previously covered topics as well as to future topics such as the pancreas and nervous system are made. The students will be challenged by the numerous exam-style questions, all of which have mark schemes embedded into the PowerPoint to allow for immediate assessment of progress.

This lesson describes why a disease would be deemed to be an autoimmune disease and describes the mechanisms involved in a few examples. The PowerPoint and accompanying worksheets have been primarily designed to cover point 4.1.1 (k) of the OCR A-level Biology A specification, but this lesson can also be used to revise the content of modules 2 and 3 and the previous lessons in 4.1.1 through the range of activities included The lesson begins with a challenge, where the students have to recognise diseases from descriptions and use the first letters of their names to form the term, autoimmune. In doing so, the students will immediately learn that rheumatoid arthritis, ulcerative colitis, type I diabetes mellitus, multiple sclerosis and myasthenia gravis are all examples of autoimmune diseases. The next part of the lesson focuses on the mechanism of these diseases where the immune system cells do not recognise the antigens (self-antigens) on the outside of the healthy cells, and therefore treats them as foreign antigens, resulting in the production of autoantibodies against proteins on these healthy cells and tissues. Key details of the autoimmune diseases stated above and lupus are described and links to previously covered topics as well as to future topics such as the nervous system are made. The students will be challenged by numerous exam-style questions, all of which have mark schemes embedded into the PowerPoint to allow for immediate assessment of progress.

This lesson describes the means of transmission of animal and plant communicable pathogens, including direct and indirect transmission. The PowerPoint and accompanying worksheets have been primarily designed to cover point 4.1.1 (b) of the OCR A-level Biology A specification but intricate planning ensures that the students are constantly challenged on their recall of the content of the previous lesson, where the different types of pathogens that cause communicable diseases in plants and animals was covered. The lesson contains a wide range of tasks which will engage the students whilst challenging them to think about the biological content. Relevant examples such as the UK government’s public message of “HANDS, FACE, SPACE” are used to explain how TB and HIV are directly transmitted through droplet infection or the exchange of bodily fluids. A series of exam-style questions challenge the students on their knowledge of the transmission of HIV and the mark scheme is embedded into the PowerPoint to allow them to assess their progress. Students will learn that although HIV is mainly a sexually transmitted infection, the sharing of needles by intravenous drug users and vertical transmission from a mother to foetus (or baby) are other mechanisms for the spread. Moving forwards, the next part of the lesson focuses on the transmission of cholera and malaria in unsafe water and through a vector respectively. Time is taken to emphasise the meaning of a vector and student understanding is checked later in the lesson when discussing the spread of the fungus responsible for Dutch elm disease by the elm beetle. The effect of climate and social factors are also considered, and the outbreak of cholera in Yemen in 2016 is used to introduce a number of the social determinants that affect transmission. The final part of the lesson describes the direct and indirect means of transmission of plant pathogens and biological examples are sourced to increase the relevance.

This lesson describes how cholera, measles, malaria, TB and HIV are transmitted from an infected individual to an uninfected individual. The PowerPoint and accompanying worksheet have been primarily designed to cover point 10.1 [c] of the CIE A-level Biology specification but intricate planning ensures that the students are constantly challenged on their recall of the content of the previous lesson where the names and types of pathogens that caused these diseases was covered. The lesson contains a wide range of tasks which will engage the students whilst challenging them to think about the biological content. Relevant examples such as the UK government’s public message of “HANDS, FACE, SPACE” are used to explain how measles, TB and HIV are directly transmitted through droplet infection or the exchange of bodily fluids. A series of exam-style questions challenge the students on their knowledge of the transmission of HIV and the mark scheme is embedded into the PowerPoint to allow them to assess their progress. The rest of the lesson focuses on the transmission of cholera and malaria in unsafe water and through a vector respectively. Again, the students are challenged to recall the name and type of pathogen that is the causative organism before details of the spread are discussed and described.

This lesson explains the difference between non-infectious and infectious diseases and names the pathogens that cause examples of the latter. The PowerPoint and accompanying worksheets have been primarily designed to cover points 10.1 (a & b) of the CIE A-level Biology specification but as this is the first lesson in topic 10, links to upcoming topics such as the immune response and vaccinations are introduced. The lesson begins with a challenge where the students have to use descriptions to recognise CHD, HIV and TB as diseases that are commonly referred to by their abbreviations. This leads into a description of the meaning of disease before the students are challenged to use any prior knowledge of this topic to recognise that CHD is an examples of a non-infectious disease whereas HIV and TB are examples of infectious diseases. Specification point 10.1 (a) states that students should know about sickle cell anaemia and lung cancer so the next section of the lesson focuses on the key details of these diseases and when considering the former, their knowledge of gene mutations, protein synthesis and haemoglobin is tested. viruses - HIV/AIDS, influenza, measles, smallpox bacteria - TB, cholera, protoctista - malaria The infectious diseases shown above are covered by the remainder of this lesson and the differing mechanisms of action of these three types of pathogens are discussed and considered throughout. For example, time is taken to describe how HIV uses a glycoprotein to attach to T helper cells whilst toxins released by bacteria damage the host tissue and the Plasmodium parasite is transmitted from one host to another by a vector to cause malaria. The accompanying worksheets contain a range of exam-style questions, including a mathematical calculation, and mark schemes are embedded into the PowerPoint to allow students to immediately assess their understanding.

This lesson describes the different types of pathogens that can cause communicable diseases in plants and animals. The PowerPoint and accompanying worksheets have been primarily designed to cover point 4.1.1 (a) of the OCR A-level Biology specification but as this is the first lesson in module 4, it has been specifically planned to make links to upcoming topics such as phagocytosis, vaccinations and classification. viruses - HIV/AIDS, influenza, TMV bacteria - TB, cholera, ring rot protoctista - malaria fungi - athlete’s foot, black sigatoka, ringworm, The diseases shown above are covered by the detailed content of this lesson and the differing mechanisms of action of the four types of pathogens are discussed and considered throughout. For example, time is taken to describe how HIV uses a glycoprotein to attach to T helper cells whilst toxins released by bacteria damage the host tissue and the Plasmodium parasite is transmitted from one host to another by a vector to cause malaria. The accompanying worksheets contain a range of exam-style questions, including a mathematical calculation, and mark schemes are embedded into the PowerPoint to allow students to immediately assess their understanding.

This lesson discusses how biodiversity may be considered at different levels and describes how to calculate Simpson’s Index of diversity. The PowerPoint and accompanying worksheets have primarily been designed to cover points 4.2.1 (a, c and d) of the OCR A-level Biology A specification but also make links to the upcoming topics of classification, natural selection and adaptations 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 species, population, biodiversity, community and natural selection from their respective definitions. Once biodiversity as the variety of living organisms in a habitat is revealed, the students will learn that this can relate to a range of habitats, from those in the local area to the Earth. Moving forwards, the students will begin to understand that biodiversity can be considered at a range of levels which include within a habitat, within a species and within different habitats so that they can be compared. Species richness as a measure of the number of different species in a community is met and a biological example in the rainforests of Madagascar is used to increase its relevance. However, students will also be introduced to species evenness and will learn that in order for a habitat to be deemed to be biodiverse, it must be both species rich and even. The students are introduced to an unfamiliar formula that calculates the heterozygosity index and are challenged to apply their knowledge to this situation, as well as linking a low H value to natural selection. The rest of the lesson focuses on the calculation of Simpson’s Index of diversity and a 4-step guide is used to walk students through each part of the calculation. This is done in combination with a worked example to allow students to visualise how the formula should be applied to actual figures. Using the method, they will then calculate a value of D for a comparable habitat to allow the two values to be considered and the significance of a higher value is explained. All of the exam-style questions have mark schemes embedded in the PowerPoint to allow students to continuously assess their progress and understanding.

This lesson describes how random and non-random sampling strategies can be carried out to measure the biodiversity of a habitat. The PowerPoint and accompanying worksheets are part of the first lesson in a series of 2 which have been designed to cover the content of point 4.2.1 (b) (i) of the OCR A-level Biology A specification and this lesson specifically focuses on sampling plant species. The second lesson covers the sampling of animal species using apparatus such as pooters and sweeping nets. The lesson begins with a challenge, where the students have to recognise the terms random and stratified from descriptions that were met in modules 2.1.6 and 3.1.1. This introduces the concept of sampling and emphasises its importance in the measurement of biodiversity and the students will learn that there is random sampling as well as non-random sampling, and that one of these strategies is known as stratified. The next part of the lesson focuses on the random sampling of a habitat where the results found with a quadrat are used to estimate the population of sessile species like plants. Due to the heavy mathematical content in the A-level Biology exams, a step by step guide is used to walk the students through the key stages in these calculations and includes the extra steps needed when the quadrat does not have an area of 1 metre squared. A series of exam-style questions will then challenge them to apply their understanding and mark schemes are embedded in the PowerPoint to allow them to immediately assess their progress. The use of quadrats that have been divided into 100 squares and point frames to estimate percentage ground cover are also discussed and the overall advantages and disadvantages of random sampling are considered. Moving forwards, the stratified, opportunistic and systematic strategies of non-random sampling are discussed and again the advantages and disadvantages of all three are considered. Time is taken to focus on line and belt transects and students will learn that the latter can be particularly useful when an abiotic factor appears to change across a habitat.