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.

This detailed lesson describes how recombinant DNA is produced using restriction endonucleases and DNA ligase and is inserted into other cells. The engaging PowerPoint and accompanying resources have been designed to cover points 8.18 & 8.19 of the Edexcel International A-level Biology specification. The lesson begins with a definition of genetic engineering and recombinant DNA to allow students to begin to understand how this process involves the transfer of DNA fragments from one species to another. Links are made to the genetic code and transcription and translation mechanisms, which were met in topic 2, in order to explain how the transferred gene can be translated in the transgenic organism. Moving forwards, the method involving reverse transcriptase and DNA polymerase is introduced and their knowledge of the structure of the polynucleotides and the roles of enzymes is challenged through questions and discussion points. Restriction endonucleases are then introduced and time is taken to look at the structure of a restriction site as well as the production of sticky ends due to the staggered cut on the DNA. A series of exam-style questions with displayed mark schemes are used to allow the students to assess their current understanding. The second half of the lesson looks at the culture of transformed host cells as an in vivo method to amplify DNA fragments. Students will learn that bacterial cells are the most commonly transformed cells so the next task challenges their recall of the structures of these cells so that plasmid DNA can be examined from that point onwards. Time is taken to explore the finer details of each step such as the addition of the promoter and terminator regions, use of the same restriction enzyme to cut the plasmid as was used to cut the gene and the different types of marker genes. As well as understanding and prior knowledge checks, quick quiz competitions are used throughout the lesson to introduce key terms such as cDNA and EcoR1 in a fun and hopefully memorable way

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 main stages of mitosis and explains the significance of this type of nuclear division for the daughter cells produced by the cycle. The PowerPoint and accompanying resources have been designed to cover points 6 (a & b) in topic 6 of AS unit 1 of the WJEC A-level Biology specification and the process of cytokinesis is also described. Depending upon the exam board taken at GCSE, the knowledge and understanding of mitosis 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 so that existing errors are addressed and key points are emphasised throughout. Their understanding of interphase is challenged at the start of the lesson to ensure that they realise that it is identical pairs of sister chromatids that enter the M phase. The main part of the lesson focuses on prophase, metaphase, anaphase and telophase and describes how the chromosomes behave in these stages. There is a focus on the centrioles and the spindle fibres that they produce which contract to drag one chromatid from each pair in opposite directions to the poles of the cell. The remainder of the lesson is 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 quiz 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.

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 how tissue fluid is formed and reabsorbed in order to emphasise its importance as the link between the blood and cells. The PowerPoint and accompanying resources have been designed to cover point (h) in topic 3 of AS unit 2 of the WJEC A-level Biology specification and explains how a combination of the effects of hydrostatic pressure and oncotic pressure results in the formation of tissue fluid in animals. The lesson begins with an introduction to the arteriole and venule end of a capillary as these will need to be considered as separate entities when describing the formation of tissue fluid. A quick quiz competition introduces a value for the hydrostatic pressure at the arteriole end and students are challenged to first predict some parts of the blood will move out of the capillary as a result of the push from the hydrostatic pressure and this allows oncotic pressure to be initially explored. The main part of the lesson uses a step by step guide to describe how the net movement is outwards at the arteriole end before students will use this guidance to describe what happens at the venule end. In the concluding part of the lesson, students will come to recognise oedema as a condition where tissue fluid accumulates and they again are challenged to explain how this occurs before they finally learn how the fluid is returned to the circulatory system as lymph

This fully-resourced lesson describes the range of potential treatments for kidney failure. The PowerPoint and accompanying resources have been designed to cover specification point (h) in topic 7 of A2 unit 3 of the WJEC A-level Biology specification. This lesson involves the diagnosis of a number of different kidney-related conditions and the potential treatments for kidney failure. This lesson is designed to get the students to take on the numerous roles of a doctor who works in the renal ward which include testing, diagnosis and treatment. Having obtained measurements by GFR and results by taking urine samples, hey are challenged to use their knowledge of the function of the kidney to study urine samples (and the accompanying GP’s notes) to diagnose one of four conditions. They then have to write a letter to the patient to explain how they made this diagnosis, again focusing on their knowledge of the structure and functions of the Bowman’s capsule and PCT. The rest of the lesson focuses on haemodialysis, peritoneal dialysis and kidney transplant. There are regular progress checks throughout the lesson so that students can assess their understanding and there are a number of homework activities included in the lesson.

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 the effects of pH on the rate of enzyme-controlled reactions. The PowerPoint and accompanying resources are part of the third lesson in a series of 5 lessons which have been designed to cover the content of point 1.4.2 (Many proteins are enzymes) of the AQA A-level Biology specification. The lesson begins with a short discussion, where the students are challenged to identify how the stomach and the small intestine differ in terms of a particular condition and to explain why the conditions in these neighbouring digestive organs are so important. This introduces pepsin and trypsin and these protease enzymes play a key role throughout the lesson as they are good examples of how different extracellular enzymes have different optimum pH values (which are not necessarily 7.0). Moving forwards, students will discuss how the rate of an enzyme-controlled reaction will change if there are small or large changes in pH, and then time is taken to ensure that students can explain these changes with reference to tertiary structure bonds and the shape of the active site. Through the use of a quick quiz competition, the students will be reminded of the key term “buffer” and a series of questions are used to challenge their understanding of how these substances could be used in a practical investigation. They will also learn how buffers are found in blood plasma as well as in red blood cells in the form of haemoglobin. With there being such a large proportion of marks for Maths in a Biology context questions in the AQA assessments, the remainder of the lesson challenges the students to use a given formula to calculate the pH of blood when given the hydrogen ion concentration and to calculate percentage decrease. These questions have been differentiated to give assistance to those that need the support

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 lesson resource contains a engaging PowerPoint and accompanying worksheets, all of which have been designed to cover the content of specification point 2.5 (d) on the WJEC GCSE Biology specification. This specification point states that students should know the components of a reflex arc. This lesson builds on the knowledge from the previous lesson on the structure and function of the nervous system (2.5b). The lesson begins by challenging the students to come up with the word reflex having been presented with 5 other synonyms of the word automatic. This leads into a section of discovery and discussion where students are encouraged to consider how a reflex arc can be automatic and rapid despite the fact that the impulse is conducted into the CNS like any other reaction. Students will be introduced to the relay neurone and will learn how this provides a communication between the sensory neurone and the motor neurone and therefore means that these arcs do not involve processing by the brain. Moving forwards, the main task of the lesson challenges the students to write a detailed description of a reflex arc. Assistance is given on the critical section which involves the relay neurone in the spinal cord before they have to use their knowledge of nervous reactions to write a paragraph before and after to complete the description. As a final task, students will have to compare the structure and functions of sensory, motor and relay neurones. Although this lesson has been designed for students studying on WJEC GCSE Biology course, it is also suitable for older students who are studying reflex reactions at A-level and need to recall the main details.