This lesson describes the relationship between the size of an organism or structure and its surface to volume ratio. The PowerPoint and accompanying worksheets have been designed to cover point 3.1 of the AQA A-level Biology specification and also have been specifically planned to prepare the students for the upcoming lessons in topic 3 on gas exchange and absorption in the ileum. The students are likely to have been introduced to the ratio at GCSE, but understanding of its relevance tends to be mixed. Therefore, real life examples are included throughout the lesson that emphasise the importance of the surface area to volume ratio in order to increase this relevance. A lot of students worry about the maths calculations that are associated with this topic so a step by step guide is included at the start of the lesson that walks them through the calculation of the surface area, the volume and then the ratio. Through worked examples and understanding checks, SA/V ratios are calculated for cubes of increasing side length and living organisms of different size. These comparative values will enable the students to conclude that the larger the organism or structure, the lower the surface area to volume ratio. A differentiated task is then used to challenge the students to explain the relationship between the ratio and the metabolic demands of an organism and this leads into the next part of the lesson, where the adaptations of larger organisms to increase the ratio at their exchange surfaces is covered. The students will calculate the SA/V ratio of a human alveolus (using the surface area and volume formulae for a sphere) and will see the significant increase that results from the folding of the membranes. This is further demonstrated by the villi and the microvilli on the enterocytes that form the epithelial lining of these folds in the ileum. The final part of the lesson introduces Fick’s law of diffusion so that students are reminded that the steepness of a concentration gradient and the thickness of a membrane also affect the rate of diffusion.

This revision lesson has been designed to challenge the students on their use of a range of mathematical skills that could be assessed on the AQA GCSE Combined Science papers. The mathematical element of the AQA GCSE Combined Science course has increased significantly since the specification change and therefore success in those questions which involve the use of maths can prove to be the difference between one grade and another or possibly even more. The engaging PowerPoint and accompanying resources contain a wide range of activities that include exam-style questions with displayed mark schemes and explanations so that students can assess their progress. Other activities include differentiated tasks, class discussion points and quick quiz competitions such as “YOU DO THE MATH” and “FILL THE VOID”. The following mathematical skills (in a scientific context) are covered in this lesson: The use of Avogadro’s constant Rearranging the formula of an equation Calculating the amount in moles using mass and relative formula mass Calculating the relative formula mass for formulae with brackets Using the Periodic Table to calculate the number of sub-atomic particles in atoms Changes to electrons in ions Balancing chemical symbol equations Converting between units Calculating concentration in grams per dm cubed and volumes of solutions Calculating size using the magnification equation Using the mean to estimate the population of a sessile species Calculating percentages to prove the importance of biodiversity Calculating percentage change Calculating the acceleration from a velocity-time graph Recalling and applying the Physics equations Understanding prefixes that determine size Leaving answers to significant figures and using standard form Helpful hints and step-by-step guides are used throughout the lesson to support the students and some of the worksheets are differentiated two ways to provide extra assistance. Due to the detail of this lesson, it is estimated that it will take in excess of 3 hours of GCSE teaching time to cover the tasks and for this reason it can be used over a number of lessons as well as during different times of the year for revision.

This fully-resourced lesson with differentiated resources has been written to prepare students for the range of mathematical-based questions they may face on the two Edexcel GCSE Chemistry papers. The lesson has been designed to contain a wide range of activities which includes 8 quiz competition rounds spread across the duration of the lesson to maintain engagement whilst the students assess their understanding. The mathematical skills covered in this lesson include: Calculating the number of sub-atomic particles in atoms and ions Writing chemical formulae for ionic compounds Identifying isotopes Calculating the relative atomic mass using isotope mass and abundance Using Avogadro’s constant to calculate the number of particles Calculating the relative formula mass Calculating amount in moles using the mass and the relative formula mass Balancing chemical symbol equations Calculating reacting masses Gas calculations using molar volume Calculating concentration of solutions Titration calculations Deducing the empirical formula Calculating energy changes in reactions Most of the resources have been differentiated two ways to allow students of differing abilities to access the work whilst still being challenged. In addition, step by step guides are used to demonstrate how to carry out some of the more difficult calculations such as the harder mole calculations and calculating masses in reactions This lesson could be used with higher ability students on the Edexcel GCSE Combined Science course by taking out the sections which are not applicable.

This highly detailed, fully-resourced lesson has been designed to cover the content of specification point 5.1.4 (d) of the OCR A-level Biology A specification which states that students should be able to demonstrate and apply an understanding of the regulation of blood glucose concentration. There is focus on the negative feedback mechanisms that release insulin or glucagon and the role of the liver. It challenges the students recall of the control of insulin release from the beta cells which was taught in an earlier lesson. A wide range of activities will maintain motivation and engagement whilst the content is covered in detail to enable the students to explain how the receptors in the pancreas detect the concentration change and how the hormones attaching to receptor sites on the liver triggers a series of events in this effector organ. This is a topic which has a huge amount of difficult terminology so time is taken to look at all of the key words, especially those which begin with the letter G so students are able to use them accurately in the correct context. The action of adrenaline is also considered and linked to the breakdown of glycogen to glucose during glycogenolysis. This lesson has been written for students studying on the OCR A-level Biology A course and ties in with the lesson on the differences between type I and II diabetes mellitus as well as the human endocrine system

A detailed lesson presentation (37 slides) and associated worksheets that looks at the different pieces of evidence that scientists use to support evolution and discusses how these support the theory. The lesson begins by challenging students to decide which piece of evidence is the key piece in supporting evolution (fossils). Students will then have to arrange a number of statements to describe how a fossil is formed. Students are introduced to the fossil record and questions are used to check that they understand where the oldest fossils would be found. Moving forwards, students are given three pieces of evidence that would be observed in the fossil record and they are challenged to explain how each of these supports the theory of evolution. Quick competitions are then used to get the students to see some extinct organisms in the Dodo and Woolly Mammoth and again they are questioned on how extinct animals support the theory of evolution. Further evidence in rapid changes in species and molecular comparison is discussed. There are regular progress checks throughout the lesson so that students can assess their understanding and there is a set homework included.

This fully-resourced lesson describes how the eukaryotic cells of complex multicellular organisms become specialised for specific functions. The detailed and engaging PowerPoint and accompanying resources have been designed to cover the 3rd part of point 2.1.1 of the AQA A-level Biology specification and also describes how these specialised cells are organised into tissues, organs and organ systems. The start of the lesson focuses on the difference in the SA/V ratio of an amoeba and a human in order to begin to explain why the process of differentiation is critical for multicellular organisms. Students will discover that a zygote is a stem cell which can express all of the genes in its genome and divide by mitosis. Time is then taken to introduce gene expression as this will need to be understood in the later topics of the course. Moving forwards, the lesson uses the process of haematopoiesis from haematopoietic stem cells to demonstrate how the red blood cell and neutrophil differ significantly in structure despite arising from the same cell along the same cell lineage. A series of exam-style questions will not only challenge their knowledge of structure but also their ability to apply this knowledge to unfamiliar situations. These differences in cell structure is further exemplified by the epithelial cells of the respiratory tract and students will understand why the shape and arrangement of these cells differ in the trachea and alveoli in line with function. The link between specialised cells and tissues is made at this point of the lesson with these examples of epithelium and students will also see how tissues are grouped into organs and then into organ systems. The remainder of the lesson focuses on specialised plant cells and the differing shapes and features of the palisade and spongy mesophyll cells and the guard cells are covered at length and in detail. Step by step guides will support the students so that they can recognise the importance of the structures and links are made to upcoming topics such as diffusion, active transport and osmosis so that students are prepared for these when covered in the future. This lesson has been written to continually tie in with the previous two lessons in this specification point which are uploaded under the titles of the structure of eukaryotic animal and plant cells.

This lesson introduces the key inorganic ions that are involved in biological processes and includes cations and anions. The engaging PowerPoint and accompanying resources have been designed to cover point 2.1.2 § of the OCR A-level Biology A specification but also makes links to topics in upcoming modules such as respiration, photosynthesis and neuronal communication. The roles of the following ions are covered in this lesson: phosphate nitrate chloride hydroxide hydrogencarbonate hydrogen ammonium sodium potassium calcium Extra time is taken during the lesson to describe how these ions are involved in the transport of carbon dioxide, the conduction of nervous impulses and blood clotting as well as other processes and a number of quiz competitions have been included to introduce key terms in a fun and memorable way

This fully-resourced lesson describes how Mycobacterium tuberculosis and human immunodeficiency virus infect human cells and cause symptoms. The PowerPoint and accompanying resources have been designed to cover point 6.6 in unit 4 of the Edexcel International A-level Biology specification and ties in closely with the previous lesson where the structure of bacteria and viruses were compared. The lesson begins by ensuring that students recognise that TB is caused by the infection of a species of bacteria known as Mycobacterium tuberculosis and they will challenged to use their knowledge of scientific classification to recall that this pathogen is found in the mycobacteria genus. At this point, the students are told that the cell walls of this genus contain mycolic acids and later in the lesson they will have to work out that this specialist feature enables this pathogen to survive phagocytosis. A series of exam-style questions will challenge their knowledge of the respiratory and immune systems as they can understand how the bacterium travels to the alveoli where it is engulfed by a macrophage. Key terms like granuloma and necrosis are introduced and the sequence of events that occur following the formation of this aggregate of cells is described. The structure of viruses was covered during the previous lesson, so this next part of the lesson starts by challenging the students to recall the capsid, genetic material in the form of viral RNA and the lipid envelope. At this point, the students are introduced to gp120, the glycoprotein which is exposed on the surface of the lipid envelope, as this structure is critical for the entry of the virus into host cells. Students will annotate a basic diagram of HIV with these four structures which also has gp41 labelled. A quick quiz competition introduces the names of the enzymes found inside the capsid Moving forwards, the main task of this part of the lesson describes how HIV binds to the helper T cells, injects its capsid and integrates its DNA into the host’s genome in order to replicate to form virus particles (virions). Students are guided through the formation of a detailed answer about the mechanism of HIV and have to input key terms and structures where information is missing. Students will learn that the increase in the number of virus particles and a decrease in helper T cells and other immune cells results in infections like TB and by opportunistic pathogens and that this stage is recognised as AIDS

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.

A fully resourced lesson which includes an informative lesson presentation (34 slides) and differentiated worksheets that show students how to convert between units so they are confident to carry out these conversions when required in Science questions. The conversions which are regularly seen at GCSE are covered as well as some more obscure ones which students have to be aware of. A number of quiz competitions are used throughout the lesson to maintain motivation and to allow the students to check their progress in an engaging way This lesson has been designed for GCSE students but is suitable for KS3

The AQA specification states that a minimum of 10% of the marks across the 3 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 resource has been designed to motivate students whilst they evaluate their understanding of the content in modules 1, 2, 3 and 5 of the OCR A-level Biology A specification which can be assessed in PAPER 1 (Biological processes). The resource includes a detailed and engaging Powerpoint (149 slides) and is fully-resourced with differentiated worksheets that challenge the students on a wide range of topics. The resource has been written to include different types of activities such as exam questions with explained answers, understanding checks and quiz competitions. The aim was to cover as much of the specification content as possible but the following topics have been given particular attention: Monosaccharides, disaccharides and polysaccharides Glycogen and starch as stores and providers of energy The homeostatic control of blood glucose concentration Osmoregulation Lipids Ultrafiltration and selective reabsorption Diabetes mellitus Voluntary and involuntary muscle The autonomic control of heart rate The organisation of the nervous system The gross structure of the human heart Haemoglobin and the Bohr shift Bonding The ultrastructure of plant cells Cyclic vs non-cyclic photophosphorylation Oxidative phosphorylation Anaerobic respiration in eukaryotes Helpful hints and tips are given throughout the resource to help students to structure their answers. This resource can be used in the lead up to the actual Paper 1 exam or earlier in the course when a particular area of modules 1, 2, 3 or 5 is being studied. If you are happy with this resource, why not look at the one which has been designed for Paper 2 (Biological diversity)?

This fully-resourced lesson explores how new species arise when changes in the gene pool of two populations prevents members from interbreeding and producing fertile offspring. The engaging PowerPoint and accompanying resources have been designed to cover the fifth part of point 7.3 of the AQA A-level Biology specification which states that students should be able to describe allopatric and sympatric speciation. The lesson begins by using the example of a hinny, which is the hybrid offspring of a horse and a donkey, to challenge students to recall the biological classification of a species. Moving forwards, students are introduced to the idea of speciation and the key components of this process, such as isolation and selection pressures, are covered and discussed in detail. Understanding and prior knowledge checks are included throughout the lesson to allow the students to not only assess their progress against the current topic but also to make links to earlier topics in the specification. Time is taken to look at the details of allopatric speciation and how the different mutations that arise in the isolated populations and genetic drift will lead to genetic changes. The example of allopatric speciation in wrasse fish because of the isthmus of Panama is used to allow the students to visualise this process. The final part of the lesson considers sympatric speciation and again a wide variety of tasks are used to enable a deep understanding to be developed.

This fully-resourced lesson describes how rod cells in the mammalian retina detect stimuli to allow vision in low light intensity. The detailed PowerPoint and accompanying resources have been designed to cover the second part of point 8.5 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification and includes reference to the roles of rhodopsin, opsin, retinal, sodium ions, cation channels and hyperpolarisation in the formation of action potentials in the optic neurones. It is likely that students will be aware that the human retina contains rod and cone cells, so this lesson builds on that knowledge and adds the detail needed at this level. Students will discover that the optical pigment in rod cells is rhodopsin and that the bleaching of this into retinal and opsin results in a cascade of events that allows an action potential to be initiated along the optic nerve. Time is taken to go through the events that occur in the dark and then the students are challenged to use this as a guide when explaining how the events differ in the light. Key terms like depolarisation and hyperpolarisation, that were met earlier in topic 8, are used to explain the changes in membrane potential and the resulting effect on the connection with the bipolar and ganglion cells is then described.

This lesson focuses on the key terms associated with ecosystems and describes how populations are affected by a range of factors. The PowerPoint and accompanying resources are part of the 1st lesson in a series of 4 lessons that cover the details of point 7.4 of the AQA A-level Biology specification As shown in the cover image, a modified version of the quiz competition BLOCKBUSTERS runs throughout the lesson and this introduces new terms as well as challenging students to recall key terms that were encountered in previous topics. These include population, ecosystems, competition, niche, abiotic factors and carrying capacity. Each time a term is met, time is taken to describe its meaning and to explain its relevance and context in this topic of populations in ecosystems. Exam-style questions are also used to challenge the students to apply their understanding and displayed mark schemes allow them to assess their progress. Prior knowledge checks interspersed within the lesson which check on topics such as the nitrogen cycle, adaptations and the biological classification of a species

An engaging lesson presentation (16 slides) which looks at the surface area to volume ratio and ensures that students can explain why this factor is so important to the organisation of living organisms. This is a topic which is generally poorly misunderstood by students and therefore time has been taken to design an engaging lesson which highlights the key points in order to encourage greater understanding. The lesson begins by showing students the dimensions of a cube and two answers and challenges them to work out what the questions were that produced these answers. Students are shown how to calculate the surface area and the volume of an object before it is explained how this can then be turned into a ratio. Time is taken at this point to ensure that students can apply this new-found knowledge as they have to work out which of the three organisms in the “SA: V OLYMPICS” would stand aloft the podium. Students are given the opportunity to draw conclusions from this task so that they can recognise that the larger the organism, the lower the surface area to volume ratio. The lesson finishes by explaining how larger organisms, like humans, have adapted in order to increase the surface area at important exchange surfaces in their bodies. There are regular progress checks throughout the lesson to allow the students to check on their understanding. This lesson has been written for GCSE students but is perfectly suitable for A-level students who want to look at this topic from a basic level