A Science teacher by trade, I've also been known to be found teaching Maths and PE! However, strange as it may seem, my real love is designing resources that can be used by other teachers to maximise the experience of the students. I am constantly thinking of new ways to engage a student with a topic and try to implement that in the design of the lessons.
A Science teacher by trade, I've also been known to be found teaching Maths and PE! However, strange as it may seem, my real love is designing resources that can be used by other teachers to maximise the experience of the students. I am constantly thinking of new ways to engage a student with a topic and try to implement that in the design of the lessons.
This lesson describes how molecules move across the cell membrane by the passive methods of simple and facilitated diffusion. The PowerPoint and accompanying resources have been designed to cover the first part of specification point 2.1.5 (d) [i] of the OCR A-level Biology A specification and the factors that increase the rate of diffusion are covered along with the limitations imposed by the phospholipid bilayer and the role of channel and carrier proteins.
The structure and properties of cell membranes were described in the lesson covering 2.1.5 (b), so this lesson has been written to include continual references to the content of that lesson. This enables links to be made between the movement across a cell membrane with the concentration gradient, the parts of the membrane that are involved and any features that may increase the rate at which the molecules move. A series of questions about the alveoli are used to demonstrate how a large surface area, a short diffusion distance and the maintenance of a steep concentration gradient will increase the rate of simple diffusion. One of two quick quiz rounds is then used to introduce temperature and size of molecule as two further factors that can affect simple diffusion. The remainder of the lesson focuses on facilitated diffusion and describes how transmembrane proteins are needed to move small, polar or large molecules from a high concentration to a lower concentration across a partially permeable membrane
This detailed lesson describes how the movement of water molecules by osmosis can affect both plant and animal cells. Both the PowerPoint and accompanying resources have been designed to cover specification point 2.1.5 (e) [i] as detailed in the OCR A-level Biology A specification and there is a particular focus on solutions of different water potentials.
It’s likely that students will have used the term concentration in their osmosis definitions at GCSE, so the aim of the starter task is to introduce water potential to allow students to begin to recognise osmosis as the movement of water molecules from a high water potential to a lower potential, with the water potential gradient. Time is taken to describe the finer details of water potential to enable students to understand that 0 is the highest value (pure water) and that this becomes negative once solutes are dissolved. Exam-style questions are used throughout the lesson to check on current understanding as well as prior knowledge checks which make links to previously covered topics such as the lipid bilayer of the cell membrane. The remainder of the lesson focuses on the movement of water when animal and plant cells are suspended in hypotonic, hypertonic or isotonic solutions and the final appearance of these cells is described, including any issues this may cause.
This lesson has been specifically written to tie in with the previous two lessons covering 2.1.5 (b) & (d) where the cell membrane, diffusion and active transport were described.
This fully-resourced lesson describes how selection pressures act on a gene pool and cause stabilising, directional and disruptive selection. The PowerPoint and accompanying resources have been designed to cover point 8.3 (i) of the Edexcel A-level Biology B specification which states that students should be able to identify each type of selection by its effect on different phenotypes.
The lesson begins with an introduction to the mark, release, recapture method to calculate numbers of rabbits with different coloured fur in a particular habitat. This shows changes in numbers of the organisms and sketch graphs are then constructed to show these changes in the population size. A quick quiz competition is used to engage the students whilst introducing the names of the three main types of selection before a class discussion point encourages the students to recognise which specific type of selection is represented by the rabbits. Key terminology including intermediate and extreme phenotypes and selection pressure are used to emphasise their importance during explanations. A change in the environment of the habitat and a change in the numbers of the rabbits introduces directional selection before students will be given time to discuss and to predict the shape of the sketch graph for disruptive selection. Students are challenged to apply their knowledge in the final task of the lesson by choosing the correct type of selection when presented with details of a population and answer related questions.
This fully-resourced lesson guides students through the use of the Hardy-Weinberg equation to monitor changes in allele frequencies in a population. The detailed PowerPoint and differentiated practice questions worksheets have been designed to cover point 8.3 (iv) of the Edexcel A-level Biology B 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. The rest of the lesson gives students 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
This engaging and fully-resourced lesson explores how genetic drift can arise after a population bottleneck or as a result of the Founder effect. The detailed PowerPoint and accompanying resources have been designed to cover points 8.3 (ii) & (iii) of the Edexcel A-level Biology B specification
A wide range of examples are used to show the students how a population that descends from a small number of parents will have a reduction in genetic variation and a change in the frequency of existing alleles. Students are encouraged to discuss new information to consider key points and understanding checks in a range of forms are used to enable them to check their progress and address any misconceptions. Students are provided with three articles on Huntington’s disease in South Africa, the Caribbean lizards and the plains bison to understand how either a sharp reduction in numbers of a new population beginning from a handful of individuals results in a small gene pool. Links to related topics are made throughout the lesson to ensure that a deep understanding is gained.
This fully-resourced lesson guides students through the construction of genetic crosses and pedigree diagrams for the inheritance of a single gene. The clear PowerPoint and accompanying resources have been designed to cover point 8.2 (ii) of the Edexcel A-level Biology B specification and includes the inheritance of multiple allele characteristics as well as those that demonstrate codominance.
In order to minimise the likelihood of errors and misconceptions, step by step guides have been included throughout the lesson to support the students with the following:
Writing parent genotypes
Working out the different gametes that are made following meiosis
Interpreting Punnett crosses to work out phenotypic ratios
Students can often find pedigree trees the most difficult to interpret and to explain so exemplar answers are used as well as differentiated worksheets provided to support those students who need extra assistance.
This fully-resourced lesson describes the inheritance of genes that are carried on the X chromosome and includes a particular focus on haemophilia in humans. The detailed PowerPoint and associated differentiated resources have been designed to cover specification point 8.2 (v) as detailed in the Edexcel A-level Biology B 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 red-green colour blindness 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 fully-resourced lesson has been written to support students to develop a clear understanding of 16 key genetic terms, including the 8 that are detailed in specification point 8.2 (i) of the Edexcel A-level Biology B specification. The 16 terms are genome, gene, chromosome, gene locus, homologous chromosomes, alleles, dominant, recessive, genotype, codominance, multiple alleles, autosomes, sex chromosomes, phenotype, homozygous and heterozygous.
As some of these terms were met at GCSE, this fully-resourced lesson has been designed to include a wide range of activities that build on this prior knowledge and provide clear explanations as to their meanings as well as numerous examples of their use in both questions and exemplary answers. The main task provides the students with an opportunity to apply their understanding by recognising a dominance hierarchy in a multiple alleles characteristic and then calculating a phenotypic ratio when given a completed genetic diagram. Other tasks include prior knowledge checks, discussion points to encourage students to consider the implementation of the genetic terms and quiz competitions to introduce new terms, maintain engagement and to act as an understanding check.
This lesson guides students through the use of the chi-squared test to determine the significance of the difference between observed and expected results. It is fully-resourced with a detailed PowerPoint and differentiated worksheets that have been designed to cover point 8.2 (vi) of the Edexcel A-level Biology B specification
The lesson includes a step-by-step guide to demonstrates how to carry out the test in small sections. At each step, time is taken to explain any parts which could cause confusion and helpful hints are provided to increase the likelihood of success in exam questions on this topic. Students will understand how to use the phenotypic ratio to calculate the expected numbers and then how to find the critical value in order to compare it against the chi-squared value. A worked example is used to show the working which will be required to access the marks and then the main task challenges the students to apply their knowledge to a series of questions of increasing difficulty.
This is the final lesson of topic 8.2 (transfer of genetic information) and links are made throughout the lesson to earlier parts of this topic such as dihybrid inheritance as well as to earlier topics like meiosis
This fully-resourced lesson describes how mutations, the events of meiosis and random fertilisation result in genetic variation. The engaging PowerPoint and accompanying resources have been primarily designed to cover points 8.1 (i) & (ii) of the Edexcel A-level Biology B specification but also includes activities to challenge the students on previous concepts in topics 1 and 2.
The students begin the lesson by having to identify phenotype and species from their respective definitions so that a discussion can be encouraged where they will recognise that phenotypic variation within a species is due to both genetic and environmental factors although this lesson only focuses on the genetic aspect. A range of activities, which include exam-style questions and quick quiz rounds, are used to challenge the students on their knowledge and understanding of substitution mutations, deletions, insertions, the genetic code, crossing over and independent assortment. Moving forwards, the concept of multiple alleles is introduced and students will learn how the presence of more than 2 alleles at a locus increases the number of phenotypic variants. The final section of the lesson focuses on the production of haploid gametes by meiosis and discusses how the random fertilisation of these gametes during sexual reproduction further increases variation.
This fully-resourced lesson describes how it’s possible for 1 gene to give rise to multiple products as a result of post-transcriptional modification of mRNA. The detailed PowerPoint and accompanying resources have been designed to cover point 7.2 (iii) of the Edexcel A-level Biology B specification.
The lesson begins with a knowledge recall as the students have to recognise the definition of a gene as a sequence of bases on a DNA molecule that codes for a sequence of amino acids in a polypeptide chain. This description was introduced in topic 1 and the aim of the start of the lesson is to introduce the fact that despite this definition, most of the nuclear DNA in eukaryotes doesn’t actually code for proteins. A quick quiz competition is then used to introduce exons as the coding regions within a gene before students are challenged to predict the name of the non-coding regions and then to suggest a function for these introns. At this point, the students will complete a task that acts as a prior knowledge check where they have to identify the 6 errors in the descriptive passage about the lac operon and its role in the regulation of gene expression in prokaryotes. Moving forwards, pre-mRNA as a primary transcript is introduced and students will learn that this isn’t the mature strand that moves off to the ribosome for translation. Instead, a process called splicing takes place where the introns are removed and the remaining exons are joined together. Another quick quiz round leads to an answer of 20000 and students will learn that this is the number of protein-coding genes in the human genome. Importantly, the students are then told that the number of proteins that are synthesised is much higher than this value and a class discussion period encourages them to come up with biological suggestions for this discrepancy between the two numbers. The lesson concludes with a series of understanding and application questions where students will learn that alternative splicing enables a gene to produce more than a single protein and that this natural phenomenon greatly increases biodiversity.
This fully-resourced lesson describes the role of transcription factors in the regulation of gene expression. The detailed PowerPoint and accompanying resources have been designed to cover the details of specification points 7.2 (i) and (ii) of the Edexcel A-level Biology B course.
This is one of the more difficult concepts in this A-level course and therefore key points are reiterated throughout this lesson to increase the likelihood of student understanding and to support them when trying to make links to actual biological examples in living organisms. There is a clear connection to transcription and translation as covered in topic 1.4, so the lesson begins by reminding students that in addition to the structural gene in a transcription unit, there is the promotor region where RNA polymerase binds. Students are introduced to the idea of transcription factors and will understand how these molecules can activate or repress transcription by enabling or preventing the binding of the enzyme. At this point, students are challenged on their current understanding with a series of questions about DELLA proteins so they can see how these molecules prevent the binding of RNA polymerase. Their understanding is then tested again with another example with oestrogen and the ER receptor. The final and main section of the lesson focuses on the lac operon. Students will be able to visualise the different structures that are found in this unit of DNA and time is taken to go through the individual functions. A step by step guide is used to walk students through the sequence of events that occur when lactose is absent and when it is present before they are challenged to apply their understanding to an exam question.
This fully-resourced lesson describes the structure, different roles and modes of action of the B and T lymphocytes in the specific immune response. The detailed PowerPoint and accompanying resources have been designed to cover point 4.1.1 (f) as detailed in the OCR A-level Biology A specification and the structure of antibodies and the roles of memory cells is also briefly introduced so that students are prepared for an upcoming lesson on the secondary immune response (4.1.1 g)
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 cellular 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. The remainder of the lesson focuses on the role of the antibodies and the attachment of phagocytes to opsonins
This lesson describes the structure and mode of action of phagocytes and focuses on the neutrophils and macrophages as APCs. The engaging and detailed PowerPoint and accompanying resources have been designed to cover point 4.1.1 (e) [i] of the OCR A-level Biology A specification and also includes an introduction to antigen-presentation so that the students are prepared for the next lesson on the specific immune response
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 a brief introduction to lymphocytes so that initial links between phagocytosis and the specific immune response is made.
This lesson describes the differences between the primary and secondary responses and describes how the structure of antibodies is related to function. The PowerPoint and accompanying resources have been designed to cover specification points 4.1.1 (g), (h) and (i) as detailed in the OCR A-level Biology A specification and emphasises the importance of memory cells.
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 distinguishes between active and passive, natural and artificial immunity and describes the principles of vaccinations. The engaging and detailed PowerPoint and accompanying resources which are differentiated have been designed to cover points 4.1.1 (j) & (l) of the OCR A-level Biology A specification and there is also a description and discussion about the concept of herd immunity.
In a previous lesson in module 4.1.1, students were introduced to 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 fully-resourced lesson compares the structure and ultrastructure of a prokaryotic cell against an eukaryotic cell. The engaging PowerPoint and accompanying resources have been designed to cover specification point 2.1.1 (k) as detailed in the OCR A-level Biology A specification and describes how the size and cell structures differ as well as the additional features that are found in some prokaryotic cells and briefly introduces binary fission.
A clear understanding of terminology is important for A-level Biology so this lesson begins with a challenge, where the students have to come up with a 3-letter prefix that they believe will translate as before or in front of . This leads into the discovery of the meaning of prokaryote as before nucleus which acts to remind students that these types of cell lack this cell structure. Links to the previous lessons on the eukaryotic cells are made throughout the lesson and at this particular point, the students are asked to work out why the DNA would be described as naked and to state where it will be found in the cell. Moving forwards, the students will discover that these cells also lack membrane bound organelles and a quick quiz competition challenges them to identify the specific structure that is absent from just a single word. In addition to the naked DNA, students will learn that there are also ribosomes in the cytoplasm and will discover that these are smaller than those found in the cytoplasm of an eukaryotic cell (but the same size as those in chloroplasts and mitochondria). The remainder of the lesson focuses on the composition of the cell wall, the additional features of prokaryotic cells such as plasmids and there is also the introduction of binary fission as the mechanism by which these organisms reproduce so that students can recognise that these cells do not contain centrioles
This engaging lesson describes how chromosome mutations result in changes to the number or structure of chromosomes and focuses on Downs and Turner’s syndrome. The PowerPoint and accompanying resources have been designed to cover specification points 2.3 (vi) and (vii) as detailed in the Edexcel A-level Biology B specification.
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 Downs, 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 Downs 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 fully-resourced lesson describes the stages of meiosis and specifically the events which contribute to genetic variation. The detailed PowerPoint and accompanying resources have been designed to cover specification points 2.3 (iv) & (v) of the Edexcel A-level Biology B specification and includes description of crossing over, independent assortment and the production of haploid gametes
In order to understand how the events of meiosis like crossing over and random 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 segregation of chromosomes and chromatids during anaphase I and II results in genetically different gametes. 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 questions which challenge the students to apply their knowledge to potentially unfamiliar situations.
This fully-resourced lesson describes the events of the cell cycle so that students can understand how the genetic material behaves in interphase, mitosis and cytokinesis. The detailed PowerPoint and accompanying resources have been designed to cover specification points 2.3 (i), (ii) and (iii) as detailed in the Edexcel A-level Biology B specification.
Depending upon the exam board taken at GCSE, the knowledge and understanding of mitosis and the cell cycle will differ considerably between students and there may be a number of misconceptions. This was considered at all points during the planning of the lesson and to address existing errors, key points are emphasised throughout. The cell cycle is introduced at the start of the lesson and the quantity of DNA inside the parent cell is described as diploid and as 2n. A quiz competition has been written into the lesson and this runs throughout, challenging the students to identify the quantity of DNA in the cell (in terms of n) at different points of the cycle. Moving forwards, the first real focus is interphase and the importance of DNA replication is explained so that students can initially recognise that there are pairs of identical sister chromatids and then can understand how they are separated later in the cycle. The main part of the lesson focuses on prophase, metaphase, anaphase and telophase and describes how the chromosomes behave in these stages. An exam style question will check on their knowledge of the organelles from 2.1 and this acts to remind them that centrioles are responsible for the production of the spindle apparatus, Students will understand how the cytoplasmic division that occurs in cytokinesis results in the production of genetically identical daughter cells. This leads into a series of understanding and application questions where students have to identify the various roles of mitosis in living organisms as well as tackling a Maths in a Biology context question. The lesson concludes with a final round of MITOSIS SNAP where they only shout out this word when a match is seen between the name of a phase, an event and a picture