This lesson describes how the eyepiece graticule and stage micrometer are used to measure the size of an object with an optical microscope. The PowerPoint and accompanying resource have been designed to cover the second part of point 2.1.3 of the AQA A-level Biology specification The main task of this concise lesson involves a step by step guide which walks students through the methodology and the use of the scale on the stage micrometer to identify the size of the divisions of the eyepiece graticule. This will need them to convert between units and as this was covered in the previous lesson, a number of prior knowledge checks will check that they are able to do this. Moving forwards, the students are challenged to apply this method to a series of exam-style questions and the mark scheme is displayed on the PowerPoint so that they can assess their understanding.

This is a fast-paced lesson which goes through the main steps of selective breeding and looks at the potential risks of this process. The lesson begins by looking at the characteristics of a number of organisms that would be selected. Time is taken to ensure that students understand that selective breeding is not a new thing and has been going on for a very long time and therefore some of the problems associated with this are now being experienced. The actual process is reduced down into 5 steps which can be recalled and applied to questions. The remainder of the lesson looks at the potential issues with selective breeding. The reduction in the nose size of pugs is explored as an example of the health problems which bred animals may face. This lesson has been written for GCSE students.

This extensive and fully-resourced lesson describes the principles and explains the techniques used in the production of recombinant DNA in genetic engineering. Both the engaging PowerPoint and accompanying resources have been written to cover points 6.1.3 (f) (i & ii) of the OCR A-level Biology A 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 module 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 enzymes 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. The following key steps are described and explained: • Remove and prepare the plasmid to act as a vector • Insert the DNA fragment into the vector • Transfer the recombinant plasmid into the host cell • Identify the cells which have taken up the recombinant plasmid • Allow the transformed host cells to replicate and express the novel gene 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 memorable way.

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 fully-resourced lesson explains how genetic fingerprinting can be used to analyse DNA fragments and explores its applications in forensic science and medical diagnosis. The engaging and detailed PowerPoint and accompanying resource have been written to cover all of point 8.4.3 of the AQA A-level Biology specification Each step of the genetic fingerprinting process is covered and time is taken to ensure that key details are understood. Students will be introduced to VNTRs and will come to recognise their usefulness in human identification as a result of the variability between individuals. Moving forwards, the involvement of the PCR and restriction enzymes are discussed and students are challenged on their knowledge of this process and these substances as they were encountered in a previous sub-topic. The main section of the lesson focuses on the use of gel electrophoresis to separate DNA fragments (as well as proteins) and the key ideas of separation due to differences in base pair length or molecular mass are discussed and explained. As well as current understanding checks, an application question involving Huntington’s disease is used to challenge their ability to apply their knowledge of the process to an unfamiliar situation. The remainder of the lesson describes how the DNA is transferred to a membrane and hybridisation probes are used to create a pattern on the X-ray film. Time has been taken to make continuous links to the previous lessons in topic 8 as well as those from topic 4 where DNA, RNA and protein synthesis were introduced.

This fully-resourced lesson looks at the effects of nervous mechanisms on the heart rate. The engaging and detailed PowerPoint and accompanying resources have been designed to cover the part of point 5.1.5 (k) of the OCR A-level Biology A specification which states that students should be able to demonstrate and apply their knowledge and understanding of the control of the heart rate by the cardiovascular centre in the medulla oblongata This lesson begins with a prior knowledge check where students have to identify and correct any errors in a passage about the conduction system of the heart. This allows the SAN to be recalled as this structure play an important role as the effector in this control system. Moving forwards, the three key parts of a control system are recalled as the next part of the lesson will specifically look at the range of sensory receptors, the coordination centre and the effector. Students are introduced to chemoreceptors and baroreceptors and time is taken to ensure that the understanding of the stimuli detected by these receptors is complete and that they recognise the result is the conduction of an impulse along a neurone to the brain. A quick quiz is used to introduce the medulla oblongata as the location of the cardiovascular centre. The communication between this centre and the SAN through the autonomic nervous system can be poorly understood so detailed explanations are provided and the sympathetic and parasympathetic divisions compared. The final task challenges the students to demonstrate and apply their understanding by writing a detailed description of the control and this task has been differentiated three ways to allow differing abilities to access the work

An engaging lesson presentation (33 slides) and associated worksheets that introduces students to classification using the taxonomic levels and teaches them how to name species using the binomial naming system. The students are told about the domain system, as developed by Carl Woese, but then the lesson focuses on showing them the seven levels that come after this. Students are challenged to understand how the levels differ from each other in terms of sharing characteristics. Time is taken to focus on the five kingdoms and links are made to other topics such as prokaryotic cells to test their previous knowledge. Moving forwards, students are shown how the genus and species are used in the binomial naming system before being given lots of opportunities to assess their understanding through questions. This lesson has been written for GCSE students but is suitable for all age ranges

The Pearson Edexcel A-level Biology A (Salters Nuffield) specification states that a minimum of 10% of the marks across the assessment papers will require the use of mathematical skills. This revision lesson has been designed to include a wide range of activities that challenge the students on these exact skills because success in the maths in biology questions can prove the difference between one grade and the next! Step-by-step guides are used to walk students through the application of a number of the formulae and then exam-style questions with clear mark schemes (which are included in the PowerPoint) will allow them to assess their progress. Other activities include differentiated tasks, group discussions and quick quiz competitions such as “FROM NUMBERS 2 LETTERS” and “YOU DO THE MATH”. The lesson has been written to cover as much of the mathematical requirements section of the specification as possible but the following have been given particular attention: Hardy-Weinberg equation Chi-squared test Calculating size Converting between quantitative units Standard deviation Estimating populations of sessile and motile species Percentages and percentage change Cardiac output Geometry Due to the detail and extensiveness of this lesson, it is estimated that it will take in excess of 2/3 hours of A-level teaching time to work through the activities and it can be used throughout the duration of the course

This lesson describes how genetic diversity within, or between species, can be investigated by comparison of characteristics or biological molecules. The PowerPoint and accompanying worksheets are primarily designed to cover the content of point 4.7 of the AQA A-level Biology specification but as this is the last lesson in the topic, it has also been planned to contain a range of questions, tasks and quiz rounds that will challenge the students on their knowledge and understanding of topic 4. Over the course of the lesson, the students will discover that comparisons of measurable or observable characteristics, DNA and mRNA sequences and the primary structure of common proteins can all be used to investigate diversity. Links are continually made to prior learning, such as the existence of convergent evolution as evidence of the need to compare biological molecules as opposed to the simple comparison of phenotypes. The issues associated with a limited genetic diversity are discussed and the interesting biological example of the congenital dysfunctions consistently found in the Sumatran tigers in captivity in Australia and New Zealand is used to demonstrate the problems of a small gene pool. Moving forwards, the study of the 16S ribosomal RNA gene by Carl Woese is introduced and students will learn that this led to the adoption of the three-domain system in 1990. The final part of the lesson describes how the primary structure of proteins like cytochrome c that is involved in respiration and is therefore found in most living organisms can be compared and challenges the students to demonstrate their understanding of protein synthesis when considering the differences between humans and rhesus monkeys.

This concise lesson covers the content of specification point 5.1.5 (l) of the OCR A-level Biology A specification which states that students should be able to demonstrate and apply an understanding of the action of neuromuscular junctions. Due to a number of similarities between these structures and cholinergic synapses, this lesson uses prior knowledge of these connections between neurones to build a good understanding of the junctions. Students will discover that the events that occur at an axon tip mirror those which happen at the pre-synaptic bulb and this is then developed to look at the differences in terms of the events once the acetylcholine has bound to its receptor sites. There is a focus on the structure of the sarcolemma and time is taken to explain how the action potential is passed from this membrane to the transverse tubules in order to stimulate the release of calcium ions from the sarcoplasmic reticulum. As a result, this lesson ties in nicely with the following lesson on the contraction of skeletal muscle and students will be able to link the binding to troponin in that lesson to the release of these ions from this lesson. Both of the main tasks of the lesson have been differentiated so that students of all abilities can access the work and make progress. This lesson has been designed for those students studying on the OCR A-level Biology course and ties in nicely with the other uploaded lessons on module 5.1.5 (Animal and plant responses)

This fully-resourced REVISION LESSON has been designed to provide the students with numerous opportunities to assess their understanding of the content of module 5.2.2 (Respiration) of the OCR A-level Biology A specification. The importance of this metabolic reaction is obvious and this is reflected in the volume of questions in the terminal exams which require an in depth knowledge of the stages of both aerobic and anaerobic respiration. The lesson contains a wide range of activities that cover the following points of the specification: Glycolysis as a stage of aerobic and anaerobic respiration The use and production of ATP through respiration Anaerobic respiration in mammalian muscle tissue The stages of aerobic respiration that occur in the mitochondrial matrix Oxidative phosphorylation The use of respirometers Calculating the respiratory quotient value for different respiratory substrates Revision lessons which cover the other sub-modules of module 5 are uploaded and tie in well with this content

This fully-resourced lesson focuses on the events of meiosis which specifically contribute to genetic variation. The detailed PowerPoint and accompanying resources have been designed to cover the 4th and final part of point 4.3 of the AQA A-level Biology specification which states that students should be able to describe how meiosis produces daughter cells that are genetically different from each other. 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. Due to the detail of this lesson, it is estimated that this will take about 2 hours of A-level teaching time to deliver

This is a fully-resourced revision resource which has been designed to encourage students to evaluate their understanding of the content in TOPIC 4 of the AQA A-level Biology specification (Genetic information, variation and relationships between organisms) . The resource includes an engaging PowerPoint (96 slides) and associated worksheets, some of which have been differentiated to allow those struggling with the content to access the work. The wide range of activities which includes exam questions, quick tasks and quiz competitions will motivate the students whilst they assess their knowledge and recognise those areas which require even further attention. The lesson has been designed to cover as many sub-topics as possible but the following have been given particular attention: Classification hierarchy DNA in prokaryotes and eukaryotes The binomial naming system Phylogeny Modern day classification using biological molecules Calculating biodiversity Selection pressures and types of selections Transcription Gene mutations Physiological, behavioural and anatomical adaptations Meiosis and variation Non-disjunction The mathematical element of this topic and the course is challenged throughout the lesson and helpful hints are regularly provided to help students to structure their answers. This resource can be used as a revision aid at the end of the topic, in the lead up to AS or A2 mocks or in the lead up to the actual terminal A-level exams.

An engaging lesson presentation (75 slides) and associated worksheets that uses a combination of exam questions, quick tasks and quiz competitions to help the students to assess their understanding of the topics found within unit B7(Ecology) of the AQA GCSE Biology specification (specification unit B4.7). The topics that are tested within the lesson include: Communities Abiotic factors Biotic factors Levels of organisation Recycling materials Decomposition Deforestation Global warming Trophic levels Pyramids of biomass Transfer of biomass Students will be engaged through the numerous activities including quiz rounds like “Number CRAZY" whilst crucially being able to recognise those areas which need further attention

This lesson describes the uses and implications of pre-implantation genetic diagnosis, amniocentesis and chorionic villus sampling. The lesson PowerPoint and accompanying worksheets have been primarily designed to cover point 2.15 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification but regular links are made to the earlier content of topics 1 & 2, and their knowledge of topics including the heart and circulation, monohybrid inheritance and cystic fibrosis are tested. The lesson begins by challenging them to use this prior knowledge of topic 2 to identify the letters in the abbreviations PGD and CVS. The involvement of IVF to obtain the embryos (or oocytes) is then discussed and a series of exam-style questions are used to get them to understand how this method screens embryos prior to implantation, so that those identified as having genetic diseases or being carriers are not inserted into the female’s uterus. Mark schemes for all of the questions included in this lesson are embedded into the PowerPoint so students can constantly assess their progress. Moving forwards, Down syndrome (trisomy 21) is used as an example of a chromosomal abnormality that can be tested for using CVS or amniocentesis. Time is taken to describe the key details of both of these procedures so students have a clear understanding of the implications and the invasiveness to the female being tested. The link between amniocentesis and an increased risk of miscarriage is considered and the results of a 2006 study are used to challenge them on their data skills.

This lesson describes how to obtain and use sampling results to calculate an estimate for the population size of a sessile, slow-moving or motile organism. The PowerPoint and accompanying worksheets are part of the second lesson in a series of 4 lessons that have been designed to cover the content of topic 7.4 (Populations in ecosystems) of the AQA A-level Biology specification and includes descriptions of the use of randomly placed quadrats, quadrats along a belt transect and the mark-release-recapture method. As you can see from the image, step by step guides are included in the lesson that walk the students through each stage of the calculations and these are followed by opportunities to challenge their understanding by answering exam-style questions. Mark schemes for the 7 questions that are answered over the course of the lesson are embedded into the PowerPoint and this allows the students to assess their progress. When considering the mark-release-recapture method, the assumptions that are made and the precautions that need to be taken are considered and the students are challenged to link the changes in the numbers of rabbits to the topic of stabilising selection.