This lesson describes the main stages of meiosis and has a specific focus on those events which contribute to genetic variation. The detailed PowerPoint and accompanying resources have been designed to cover point (d) in topic 6 of AS unit 1 of the WJEC A-level Biology specification and includes description of crossing over, independent assortment, independent segregation and the production of haploid gametes In order to understand how the events of meiosis like crossing over and independent assortment and independent segregation can lead to variation, students need to be clear in their understanding that DNA replication in interphase results in homologous chromosomes as pairs of sister chromatids. Therefore the beginning of the lesson focuses on the chromosomes in the parent cell and this first part of the cycle and students will be introduced to non-sister chromatids and the fact that they may contain different alleles which is important for the exchange that occurs during crossing over. Time is taken to go through this event in prophase I in a step by step guide so that the students can recognise that the result can be new combinations of alleles that were not present in the parent cell. Moving forwards, the lesson explores how the independent assortment and segregation of chromosomes and chromatids during metaphase I and II and anaphase I and II respectively results in genetically different gametes. The key events of all of the 8 phases are described and there is a focus on key terminology to ensure that students are able to describe genetic structures in the correct context. The final part of the lesson looks at the use of a mathematical expression to calculate the possible combinations of alleles in gametes as well as in a zygote following the random fertilisation of haploid gametes. Understanding and prior knowledge checks are interspersed throughout the lesson as well as a series of exam-style questions which challenge the students to apply their knowledge to potentially unfamiliar situations. This lesson has been specifically planned to lead on from the previous two lessons on the cell cycle and the main stages of mitosis and constant references are made throughout to encourage students to make links and also to highlight the differences between the two types of nuclear division

This lesson describes the roles of the SAN and Purkyne fibres in the coordination of the three stages of the cardiac cycle. The PowerPoint and accompanying resources are part of the first lesson in a series of 2 lessons that have been designed to cover point [c] in topic 3 of AS unit 2 of the WJEC A-level Biology specification and has a specific focus on the pressure changes that occur in each stage of the cycle The start of the lesson introduces the cardiac cycle as well as the key term systole, so that students can immediately recognise that the three stages of the cycle are atrial and ventricular systole followed by diastole. Students are challenged on their prior knowledge of the structure of the heart as they have to name and state the function of an atrioventricular and semi-lunar valve from an internal diagram. This leads into the key point that pressure changes in the chambers and the major arteries results in the opening and closing of these sets of valves. Students are given a description of the pressure change that results in the opening of the AV valves and shown where this would be found on the graph detailing the pressure changes of the cardiac cycle. They then have to use this as a guide to write descriptions for the closing of the AV valve and the opening and closing of the semi-lunar valves and to locate these on the graph. By providing the students with this graph, the next part of the lesson can focus on explaining how these changes come about. Students have to use their current and prior knowledge of the chambers and blood vessels to write 4 descriptions that cover the cardiac cycle. This rest of the lesson focuses on the roles of the SAN and Purkyne fibres as well as the AVN and the bundle of His in the coordination of the heartbeat, continually linking back to the work on the cycle. The SAN is introduced as the natural pacemaker and then time is given to study each step of the conduction of the impulse as it spreads away from the myogenic tissue in a wave of excitation. Moving forwards, students are encouraged to consider why a delay would occur at the AVN and then they will learn that the impulse is conducted along the Bundle of His to the apex so that the contraction of the ventricles can happen from the bottom upwards. The structure of the cardiac muscle cells is discussed and the final task of the lesson challenges the students to describe the conducting tissue, with an emphasis on the use of key terminology.

This lesson describes the concept of homeostasis using negative feedback control and also describes the role of positive feedback. The PowerPoint and accompanying resources have been designed to cover specification points (a & b) in topic 7 of A2 unit 3 of the WJEC A-level Biology specification and explains how this feedback control maintains systems within narrow limits but has also been planned to provide important details for upcoming topics such as osmoregulation. The normal ranges for blood glucose concentration, blood pH and body temperature are introduced at the start of the lesson to allow students to recognise that these aspects have to be maintained within narrow limits. A series of exam-style questions then challenge their recall of knowledge from AS units 1 & 2 and the earlier topics in A2 unit 3 as they have to explain why it’s important that each of these aspects is maintained within these limits. The students were introduced to homeostasis at GCSE, so this process is revisited and discussed, to ensure that students are able to recall that this is the maintenance of a state of dynamic equilibrium. A quick quiz competition is used to reveal negative feedback as a key term and students will learn how this form of control reverses the original change and biological examples are used to emphasise the importance of this system for restoring levels to the limits (and the optimum). The remainder of the lesson explains how positive feedback differs from negative feedback as it increases the original change and the role of oxytocin in birth and the movement of sodium ions into a neurone are used to exemplify the action of this control system.

This engaging lesson describes how chromosome mutations result in changes to the number or structure of chromosomes The PowerPoint and accompanying resources are part of the second lesson in a series of 2 lessons that have been designed to cover specification points (f) in topic 3 of A2 unit 4 of the WJEC A-level Biology specification, and there is a key focus on Down syndrome A human karyotype which has not been altered by a mutation is studied at the start of the lesson to allow students to recall the usual number of chromosomes as well as the sex chromosomes. They are then challenged to identify the differences when presented with the karyotypes of sufferers of Down, Turner’s and Klinefelter’s syndrome. Students will learn that in the majority of cases, these conditions are the result of non-disjunction and having been assisted in the explanation of the outcome for Down and Klinefelters, they have to form their own for Turner’s. The remainder of the lesson looks at other types of mutations, including translocation, and students will also see how whole sets of chromosomes can be duplicated in polyploidy

This lesson describes the inheritance of two genes and guides students through the calculation of phenotypic ratios, before considering linkage. The PowerPoint and the accompanying resources have been designed to cover point [c] in topic 3 of A2 unit 4 of the WJEC A-level Biology specification. As the previous lesson described the construction of genetic crosses and pedigree diagrams, students are aware of the methods involved in writing genotypes and gametes for the inheritance of a single gene. Therefore, the start of this lesson builds on this understanding to ensure that students recognise that genotypes contain 4 alleles and gametes contain 2 alleles when two genes are inherited. The students are taken through the steps of a worked example to demonstrate the key steps in the calculation of a phenotypic ratio before 2 exam-style questions challenge them to apply their newly-acquired knowledge. Mark schemes are displayed within the PowerPoint to allow students to assess their progress. The phenotypic ratio generated as the answer to the next question is 9:3:3:1 and time is taken to explain that this is the expected ratio when two heterozygotes for two unlinked genes are crossed which they may be expected to use when meeting the chi squared test in an upcoming lesson The remainder of the lesson considers how linkage, where two genes have loci on the same chromosome, affects the outcome of dihybrid inheritance. This is a difficult topic which can be poorly understood by students so extra time was taken during the planning to split the concept into small chunks. There is a clear focus on using the number of parent phenotypes and recombinants in the offspring as a way to determine linkage and suggest how the loci of the two genes compare. Important links to other topics such as crossing over in meiosis are made to enable students to understand how the random formation of the point of contact (chiasma) determines whether new phenotypes will be seen in the offspring or not. Linkage is an important cause of variation and the difference between observed and expected results and this is emphasised on a number of occasions and a link to the chi squared test which is covered in an upcoming lesson is also made. The main task of the lesson act as understanding check where students are challenged to analyse the results of genetic crosses involving the inheritance of the ABO blood group gene and the nail-patella syndrome gene n humans and also the inheritance of body colour and wing length in Drosophila.

This lesson describes sex linkage, focusing on the the inheritance of genes on the X chromosome that lead to haemophilia and Duchenne muscular dystrophy. The PowerPoint and accompanying resources have been designed to cover specification point [e] in topic 3 of A2 unit 4 of the WJEC A-level Biology specification. Key genetic terminology is used throughout and the lesson begins with a check on their ability to identify the definition of homologous chromosomes. Students will recall that the sex chromosomes are not fully homologous and that the smaller Y chromosome lacks some of the genes that are found on the X. This leads into one of the numerous discussion points, where students are encouraged to consider whether females or males are more likely to suffer from sex-linked diseases and they will be challenged to find evidence to support this decision later in the lesson. In terms of humans, the lesson focuses on haemophilia and a step-by-step guide is used to demonstrate how these specific genetic diagrams should be constructed and how the phenotypes should then be interpreted. The final tasks of the lesson challenge the students to carry out a dihybrid cross that involves a sex-linked disease and an autosomal disease before applying their knowledge to a question about chickens and how the rate of feather production in chicks can be used to determine gender. All of the tasks are differentiated so that students of differing abilities can access the work and all exam questions have fully-explained, visual markschemes to allow them to assess their progress and address any misconceptions

This lesson describes how the structure of the heart and the circulatory system is related to its function. The PowerPoint lesson and accompanying resources have been designed to cover the detail of point 8.8 of the Edexcel GCSE Biology and Combined Science specifications and includes descriptions of the role of the major blood vessels, the heart valves, and the relative thickness of the chamber walls. The lesson starts with an extract from Friends and challenges the students to recognise that full sized aortic pumps is a thesaurus version of big hearts. This reiterates the basic function of the heart that was met at KS2 and KS3 and moving forwards, the students will learn that it is the contraction of the cardiac muscle in the walls of the four heart chambers that allows this to happen. Students are provided with a diagram throughout the lesson which will be annotated as new structures are encountered and they begin by labelling the two atria and ventricles. The focus of the lesson is the relationship between structure and function so time is taken to consider the different roles of the atria and ventricles, as well as the right ventricle versus the left ventricle. Students will be able to observe from their diagram that the left ventricle has the thickest wall and they will be challenged to explain why later in the lesson once more detailed knowledge has been added. The next part of the lesson introduces the pulmonary artery and vein and a task challenges the students to consider the relationship between the heart and the lungs, and their prior knowledge of the adaptations of the alveoli is also tested. The remainder of the lesson discusses the double circulatory system and the heart valves. Understanding checks are found throughout the lesson and mark schemes are embedded into the PowerPoint to allow the students to assess their progress.

This lesson introduces and explains the meaning of 11 key terms associated with the genetic inheritance topic. The PowerPoint and accompanying resources have been designed to cover point 6.1.6 of the AQA GCSE Combined Science specification and include explanations of genome, chromosome, gene, allele, genotype, homozygous, heterozygous, phenotype, dominant, recessive and gamete. The key term, genome, was met earlier in topic 6 so the lesson begins with a knowledge retrieval with the definition for this term. As the genome is the entire DNA of an organism, the next task challenges the students to identify three errors in a passage about DNA. This challenges their recall of the structure of this chemical as a double helix, its location in an eukaryotic cell in the nucleus and an understanding that the gene codes for the sequence of amino acids in a specific protein. This leads into discussions about chromosomes and genes and time is taken to explain that homologous chromosomes have the same genes at the exact same gene loci. The students will learn that alternative forms of the gene (alleles) can be found at these loci and that these structures explain the differences in inherited characteristics. Moving forwards, the main section of the lesson describes the link between the dominant and recessive alleles, homozygous and heterozygous genotypes, and the physical expression as the phenotype. The final key term is gamete, and the students are challenged to recognise a definition for this term using their knowledge of meiosis. Two progress and understanding checks complete the lesson and check on the students’ ability to recognise and write definitions for these 11 terms and to use them accurately in a written description

This engaging revision lesson challenges the students on their knowledge of the communicable diseases topic as detailed in the AQA GCSE combined science specification. The PowerPoint and accompanying resources include a range of tasks that enable the students to assess their knowledge of the 7 viral, bacterial, fungal and protist infections that are listed in topic B3.1. This lesson has been designed to be used as a final revision resource as the GCSE exams approach, or as part of revision for an end of topic test.

This lesson explores how certain farming methods reduce biodiversity and considers the importance of a balance between conservation and farming. The PowerPoint and accompanying resources are the second in a series of 2 lessons which cover the detail in point 4.6 (biodiversity within a community) of the AQA A-level biology specification. The lesson begins by challenging the students to use the % change formula to calculate the predicted population in the UK by mid 2030. This increase to almost 70 million will lead into the recognition that farmers are under constant pressure to grow and provide enough food to feed this ever-growing population. A series of tasks and discussions will consider farming methods such as continuous monoculture and herbicides and insecticides which reduce biodiversity. This introduces conservation as active management to prevent the loss of biodiversity and several methods including the CSS and buffer strips are explored to encourage the students to think about the aims of these strategies. The other lesson covering specification point 4.6 is uploaded and named “biodiversity within a community”.

This revision lesson challenges students to explain the results of an osmosis investigation and to calculate accelerations using 2 equations. The PowerPoint and accompanying resources have been designed to check on the understanding of these two topics as detailed in the AQA GCSE biology, physics and combined specifications. The lesson contains a range of tasks including worked examples, exam questions and quizzes which will remind students that water molecules move across partially permeable membranes by osmosis and how changes in the mass of a potato can be used to compare water concentrations in the potato and solution. Students will also recall that acceleration can be calculated from velocity-time graphs using change in velocity/time as well as through the use of F=ma.

This lesson revisits the topic of random and systematic errors and also challenges students on other scientific skills such as identifying variables. Students tend to find this topic confusing, so the PowerPoint and accompanying resources have been designed to support them to identify whether an error is random or systematic and then to understand what to do next. The lesson guides the students through a series of real life examples and shows them how to spot each type of error. There is a considerable mathematical element to this lesson, including the calculation of means or missing values in a table. The lesson concludes with a series of exam-style questions where the students have to apply their understanding of identifying errors, variables and calculating means.

This lesson describes succession as the gradual, progressive changes that occur in a community over time. The PowerPoint and accompanying resources are part of lesson 3 in a series of 4 lessons which have been planned to cover the content included in topic 7.4 of the AQA A-level biology specification. In line with the specification, the lesson describes primary succession and explains how the community changes from the initial colonisation by the pioneer species to the establishment of a climax community. Time is taken to focus on the lichen as a pioneer species and to explain how their actions lead to the production of soil and the subsequent colonisation by more hardy species. The island of Surtsey is used as a real-world example to deepen student understanding. Understanding checks and prior knowledge checks are embedded throughout the lesson (along with the answers) so students can assess their progress on the current topic and also test their ability to link to previously covered topics. Due to the high mathematical content of the AQA assessments, a maths in a biology context question has also been included.

This extensive revision lesson challenges students on their knowledge and understanding of the content of topics 5 - 8 of the AQA A-level specification. The PowerPoint and accompanying resources are detailed and engaging and contain a selection of tasks which challenge the following points: Directional, stabilising and disruptive selection Saltatory conduction and other factors affecting conductance speed The structure of a motor neurone Sensory receptors, depolarisation and initiation of an action potential Hardy-Weinberg principle Genetic terminology Codominance and sex-linkage Autosomal linkage Chi-squared test Phosphorylation The stages of aerobic respiration Explaining lower ATP yields in anaerobic respiration Skeletal muscle contraction Structure and function of slow and fast twitch muscle fibres The control of heart rate Electrophoresis and genetic fingerprinting The secondary messenger model The students are tested through a variety of tasks including exam questions, understanding checks, and quiz rounds to maintain engagement. Due to the mathematical content in all A-level exams, there is also a focus on these skills. The answers to all questions are embedded into the PowerPoint so students can use this resource outside of the classroom. The delivery of the whole lesson will likely need at least 2 or 3 hours of contact time so this resource could be used with students in the final weeks building up to their paper 2 exam, or alternatively with students before their mocks on these topics.

This lesson describes the biological meaning of species, populations, gene pool and allele frequency and explains how these terms are linked. The PowerPoint and accompanying resources are part of the 1st lesson in a series of 2 lessons that cover the detail of specification point 7.2 (Populations) of the AQA A-level biology. The two living species of the African elephant, the forest and bush elephant, are used as examples to demonstrate the meaning of species and to show how they exist as one or more populations. A quick quiz introduces the term gene pool in an engaging way and then the allele frequency of three versions of the GBA gene demonstrates how these frequencies can change in small populations. In doing so, students are briefly introduced to genetic drift which they will encounter in an upcoming topic. The students are challenged throughout the lesson with understanding checks and prior knowledge checks as well as exam-based questions where they have to comment on the validity of a scientist’s conclusion. The other lesson in topic 7.2 is the Hardy-Weinberg principle.

A fun and engaging lesson presentation (90 slides) and associated worksheets that uses exam questions, quick tasks and quiz competitions to allow students to assess their understanding of the topic of transport in plants, which is module 3.1.3 on the OCR A-Level Biology A specification. Competition rounds include “Keyword BINGO”, “Crack the Code” and “Make the Link” and students will enjoy being able to identify areas that require further attention. All exam questions have mark schemes. This lesson is designed for A-level students

A fun and highly engaging lesson presentation (37 slides) and associated worksheets that combines exam questions and progress checks along with competition rounds to enable students to assess their understanding of the specification content within units B1 - 3 of the OCR Gateway A 9 - 1 GCSE Science. All of the exam questions and progress checks have displayed answers as well as sections where content is recapped so that students can understand how an answer was obtained. The revision rounds in the competition include “Blockbusters”, “Doctor, Doctor” and “Crack the CODE”. This lesson has been designed for GCSE students.

A detailed and engaging lesson presentation (52 slides) and accompanying worksheet that looks at competition between organisms and the different types of relationships that exist as a result of this interaction. The lesson begins by looking at the meaning of the biological term, "competition", and then introduces this when it occurs between the same species and different species. Students are challenged to consider the different resources that animals compete for before an activity based competition is used to get them to recognise how this competition can cause changes to the population size. Moving forwards, students will meet the three main types of ecological relationship and look at them in greater detail, with predation being a main focus. There are regular progress checks throughout the lesson (with displayed answers) so that students can assess their understanding. This lesson has been designed for GCSE students but can be used with more-able KS3 students who are looking at ecosystems and the relationships that exist within them

This engaging and detailed lesson presentation (43 slides) uses a step by step guide to take students through the important scientific skill of drawing graphs to represent data and address all the misconceptions and misunderstandings that often accompany this topic. The lesson begins by explaining to the students how to decide whether data should be represented on a line graph or a bar chart and a competition called "To BAR or not to BAR" is used to allow them to check their understanding while maintaining motivation. Moving forwards, students are shown a 6 step guide to drawing a line graph. Included along the way are graphs that are wrong and explanations as to why so that students can see what to avoid. There are continuous progress checks and a homework is also included as part of the lesson. This lesson is written for students of all ages who are studying Science.