This lesson explains the effects of light intensity, carbon dioxide concentration and temperature (limiting factors) on the rate of photosynthesis. The PowerPoint and accompanying resources have been designed to cover points (1 & 2) of the CIE A-level Biology specification (for assessment in 2025-2027) and also considers how knowledge of these limiting factors can be used to increase crop yields in the protected environment of a greenhouse. The lesson has been specifically written to tie in with the previous lessons in topic 13.1 which covered the structure of the chloroplast, the light-dependent reactions and the light-independent reactions. Exam-style questions are included throughout the lesson and these require the students to explain why light intensity is important for both reactions as well as challenging them on their ability to describe how the relative concentrations of GP, TP and RuBP would change as carbon dioxide concentration decreases. There are also links to previous topics such as enzymes when they are asked to explain why an increase in temperature above the optimum will limit the rate of photosynthesis. Step by step guides are included to support them to form some of the answers and mark schemes are always displayed so that they can quickly assess their understanding and address any misconceptions. The final part of the lesson provides details of the World’s largest rooftop greenhouse in Montreal and challenges their knowledge of related topics such as cellulose structure, pollination and biological control.

This lesson describes the biuret and emulsion tests for proteins and lipids respectively and then acts as a revision lesson for topics 2.2 and 2.3. The engaging PowerPoint and accompanying resources have been designed to be taught at the end of topic 2 and uses a range of activities to challenge the students on their knowledge of that topic, but also covers the second part of point 2.1 (a) of the CIE A-level Biology specification when the qualitative tests are described. The first section of the lesson describes the steps in the biuret test and challenges the students on their recall of the reducing sugars and starch tests from topic 2.1 to recognise that this is a qualitative test that begins with the sample being in solution. The students will learn that the addition of sodium hydroxide and then copper sulphate will result in a colour change from light blue to lilac if a protein is present. The next part of the lesson uses exam-style questions with displayed mark schemes, understanding checks and quick quiz competitions to engage and motivate the students whilst they assess their understanding of this topic. The following concepts are tested during this lesson: The general structure of an amino acid The formation of dipeptides and polypeptides through condensation reactions The primary, secondary, tertiary and quaternary structure of a protein Biological examples of proteins and their specific actions (e.g. antibodies, enzymes, peptide hormones) Moving forwards, the lesson describes the key steps in the emulsion test for lipids, and states the positive result for this test. There is a focus on the need to mix the sample with ethanol, which is a distinctive difference to the tests for reducing sugars and starch and proteins. The remainder of the lesson uses exam-style questions with mark schemes embedded in the PowerPoint, understanding checks, guided discussion points and quick quiz competitions to challenge the following specification points: The structure of a triglyceride The relationship between triglyceride property and function The hydrophilic and hydrophobic nature of the phospholipid The phospholipid bilayer of the cell membrane Cholesterol is also introduced so that the students are prepared for this molecule when it is met in topic 4 (cell membranes) This is an extensive lesson and it is estimated that it will take in excess of 2 hours of allocated teaching time to cover the detail and the different tasks

This lesson describes the classification system, focusing on the biological classification of a species and the 7 taxa found above this lowest taxon. The engaging PowerPoint and accompanying resource have been designed to cover point 4.6 (i) of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification and also describes the binomial naming system which uses the genus and species. The lesson also contains links to upcoming lessons where molecular phylogeny is described and the three-domain system is covered in greater detail with a focus on the results of Carl Woese’s rRNA study The lesson begins by looking at the meaning of a population in Biology so that the term species can be introduced. A hinny, which is the hybrid offspring of a horse and a donkey, is used to explain how these two organisms must be members of different species because they are unable to produce fertile offspring. Moving forwards, students will learn that classification is a means of organising the variety of life based on relationships between organisms using differences and similarities in phenotypes and in genotypes and is built around the species concept and that in the modern-day classification hierarchy, species is the lowest taxon. A quiz runs throughout the lesson and this particular round will engage the students whilst they learn (or recall) the names of the other 7 taxa and the horse and the donkey from the earlier example are used to complete the hierarchy. Students will understand that the binomial naming system was introduced by Carl Linnaeus to provide a universal name for each species and they will be challenged to apply their knowledge by completing a hierarchy for a modern-day human, by spotting the correct name for an unfamiliar organism and finally by suggesting advantages of this system.

This lesson describes how the recent use of similarities in biological molecules and other genetic evidence has led to new classification systems. The PowerPoint and accompanying resources have been designed to cover point 4.2.2 [c] (i) of the OCR A-level Biology A specification and focuses on the introduction of the three-domain system following Carl Woese’s detailed study of the ribosomal RNA gene. The lesson begins with an introduction of Woese and goes on to describe how he is most famous for his definition of the Archaea as a new domain of life. Students were introduced to domains and the other classification taxa in a previous lesson, so their recall of this knowledge is continually tested and built upon as details are added. Students will discover the key differences between Archaea and Bacteria that led to the splitting of the prokaryotae kingdom and the addition of this higher classification rank. Moving forwards, the rest of the lesson considers other molecules that can be compared between species for classification purposes and the primary structure of cytochrome is described and discussed. At this point in the lesson, the students are also tested on their knowledge of the nature of the genetic code and have to explain how mutations to DNA can also be used for comparative purposes.

This lesson describes classification as a means of organising the variety of life based on relationships between organisms. The engaging PowerPoint and accompanying resource have been designed to cover point 4.14 (i) of the Edexcel International A-level Biology specification and focuses on the classification hierarchy where species is the lowest taxon but also describes the binomial naming system which uses the genus and species. The lesson also contains links to the next lesson where molecular phylogeny is described and the three-domain system is covered in greater detail with a focus on the results of Carl Woese’s rRNA study The lesson begins by looking at the meaning of a population in Biology so that the term species can be introduced. A hinny, which is the hybrid offspring of a horse and a donkey, is used to explain how these two organisms must be members of different species because they are unable to produce fertile offspring. Moving forwards, students will learn that classification is a means of organising the variety of life based on relationships between organisms using differences and similarities in phenotypes and in genotypes and is built around the species concept and that in the modern-day classification hierarchy, species is the lowest taxon. A quiz runs throughout the lesson and this particular round will engage the students whilst they learn (or recall) the names of the other 7 taxa and the horse and the donkey from the earlier example are used to complete the hierarchy. Students will understand that the binomial naming system was introduced by Carl Linnaeus to provide a universal name for each species and they will be challenged to apply their knowledge by completing a hierarchy for a modern-day human, by spotting the correct name for an unfamiliar organism and finally by suggesting advantages of this system.

This lesson describes how the critical evaluation of new data by the scientific community leads to new taxonomic groupings, like the three domains of life. The detailed PowerPoint and accompanying resources have been designed to cover point 4.6 (ii) of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification and focuses on the introduction of the three-domain system following Carl Woese’s detailed study of the ribosomal RNA gene. The lesson begins with an introduction of Woese and goes on to describe how he is most famous for his definition of the Archaea as a new domain of life. Students were introduced to domains and the other classification taxa in a previous lesson, so their recall of this knowledge is continually tested and built upon as details are added. Students will discover the key differences between Archaea and Bacteria that led to the splitting of the prokaryotae kingdom and the addition of this higher classification rank. Moving forwards, the rest of the lesson describes how molecular phylogeny uses other molecules and that these are compared between species for classification purposes. One of these is a protein called cytochrome which is involved in respiration and can be compared in terms of primary structure to determine relationships. At this point in the lesson, the students are also tested on their knowledge of the nature of the genetic code (as covered in topic 2) and have to explain how mutations to DNA can also be used for comparative purposes.

This lesson explains that biodiversity is considered at three levels and describes how the Simpson’s Index of Diversity is used to calculate the biodiversity within a habitat. The engaging and detailed PowerPoint and accompanying resources have been designed to cover points 18.1 (a, b & f) of the CIE A-level Biology specification and also covers the meaning of ecosystems and niche as well as some other important ecological terms that are related such as abiotic factors and population. A quiz competition called BIOLOGICAL TERMINOLOGY SNAP runs throughout the lesson and has been included to engage the students whilst challenging them to recognise key terms from their definitions. This quiz will introduce species, ecosystems, biodiversity, endemic, heterozygote, distribution and natural selection and each of these terms is put into context once introduced. A series of exam-style questions to challenge the students to explain how the distribution of fish is affected by abiotic factors in an ecosystem. Once biodiversity is revealed through the quiz competition, the students will learn that they need to consider biodiversity within a habitat, within a species and within different habitats so that they can be compared. The rest of the lesson uses step by step guides, discussion points and selected tasks to demonstrate how to determine species richness and the Simpson’s index of diversity. The heterozygosity index is also introduced as a means to consider genetic variation. Students are challenged with a range of exam-style questions where they have to apply their knowledge and all mark schemes are displayed and clearly explained within the PowerPoint to allow students to assess their understanding and address any misconceptions if they arise This is a detailed lesson with a lot of tasks (some of which are differentiated), so it is estimated that it will take in excess of 2 hours of allocated A-level teaching time to cover all of the content

This lesson describes how large molecules are hydrolysed to smaller molecules by the enzymes produced by the digestive system in mammals. The detailed PowerPoint and accompanying worksheets are part of the 1st lesson in a series of 2 which have been designed to cover the content of point 3.3 of the AQA A-level Biology specification and this lesson includes descriptions of the action of amylase, disaccharidases, lipase, endopeptidases, exopeptidases and dipeptidases. The lesson has been designed to walk the students through the functions of the digestive system at each point of the digestive tract up until the duodenum and focuses on the action of the enzymes produced in the mouth, stomach and small intestine and by the accessory organs of the system. Time is taken to describe and explain key details, such as the fact that endopeptidases cleave peptide bonds within the molecules, meaning that they cannot break down proteins into monomers. The lesson is filled with exam-style questions which will develop their understanding of the current topic as well as checking on their knowledge of related topics which have been previously-covered such as the structure of the biological molecules and qualitative tests. In addition to the detailed content and regular questioning, the lesson PowerPoint contains guided discussion periods and two quick quiz competitions which introduce a key term and a key value in a fun and memorable way This lesson has been specifically planned to prepare the students for the very next lesson where the mechanisms for the absorption of the products of digestion are described.

This lesson describes how biodiversity is generated through natural selection and leads to behavioural, anatomical and physiological adaptations. The PowerPoint and accompanying resources have been designed to cover specification points (m) & (n) in AS unit 2, topic 1 of the WJEC A-level Biology specification President Trump’s error ridden speech about antibiotics is used at the beginning of the lesson to remind students that this is a treatment for bacterial infections and not viruses as he stated. Moving forwards, 2 quick quiz competitions are used to introduce MRSA and then to get the students to recognise that they can use this abbreviation to remind them to use mutation, reproduce, selection (and survive) and allele in their descriptions of evolution through natural selection. The main task of the lesson challenges the students to form a description that explains how this strain of bacteria developed resistance to methicillin to enable them to see the principles of natural selection. This can then be used when describing how the anatomy of the modern-day giraffe has evolved over time. The concept of convergent evolution is introduced and links are made to the need for modern classification techniques as covered earlier in topic 1. Moving forwards, students will understand how natural selection leads to adaptations and a quick quiz competition introduces the different types of adaptation and a series of tasks are used to ensure that the students can distinguish between anatomical, behavioural and physiological adaptations. The Marram grass is used to test their understanding further, before a step by step guide describes how the lignified cells prevent a loss of turgidity. Moving forwards, the students are challenged to explain how the other adaptations of this grass help it to survive in its environment. A series of exam-style questions on the Mangrove family will challenge them to make links to other topics such as osmosis and the mark schemes are displayed to allow them to assess their understanding. The final part of the lesson focuses on the adaptations of the anteater but this time links back to the topic of taxonomy and students have to answer questions about species and classification hierarchy. Due to the extensiveness of this lesson and the detail contained within the resources, it is estimated that it will take in excess of 2 hours of allocated A-level teaching time to deliver this lesson.

This lesson explains the meaning of biodiversity and describes how it can be assessed in a habitat, in a species level at a genetic level and at a molecular level. The engaging PowerPoint and accompanying resources have been designed to cover points (h-l) in AS unit 2, topic 1 of the WJEC A-level Biology specification but as a lot of genetic content is covered when considering diversity within a species, this lesson can be used as an introduction to the upcoming topics of inheritance A quiz competition called BIOLOGICAL TERMINOLOGY SNAP runs over the course of the lesson and this will engage the students whilst challenging them to recognise key terms from their definitions. This quiz introduces biodiversity, loci, allele and recessive and each of these terms is put into context once introduced. Once biodiversity has been revealed, the students will learn that they are expected to be able to assess the biodiversity within a habitat and within a species and at a molecular level. The variety of alleles in the gene pool of a population increases the genetic diversity so a number of examples are used to demonstrate how the number of phenotypes increases with the number of alleles at a locus. The CFTR gene is used to demonstrate how 2 alleles results in 2 different phenotypes and therefore genetic diversity. Moving forwards, students will discover that more than 2 alleles can be found at a locus and they are challenged to work out genotypes and phenotypes for a loci with 3 alleles (shell colour in snails) and 4 alleles (coat colour in rabbits). Moving forwards, a step by step guide to complete a worked example to calculate a value of D using Simpson’s index of diversity. Students are challenged with a range of exam-style questions where they have to apply their knowledge and all mark schemes are displayed and clearly explained within the PowerPoint to allow students to assess their understanding and address any misconceptions if they arise. The final part of the lesson considers how DNA fingerprinting can be used to assess biodiversity at a molecular level and again a series of exam-style questions are used to challenge the students to apply their newly-acquired knowledge to an unfamiliar situation.

This lesson describes the adaptations of gas exchange surfaces in single-celled organisms, insects, bony fish and dicotyledonous plants. The PowerPoint and accompanying worksheets are part of the first lesson in a series of 6 lessons that have been designed to cover the detail of point 3.2 (Gas exchange) of the AQA A-level Biology specification. The lesson has been intricately planned to challenge the students on their understanding of the surface area to volume ratio (as covered in the previous lesson) and to make direct links to upcoming lessons on gas exchange and transport systems in humans. The lesson begins by explaining that single-celled organisms are able to diffuse oxygen and carbon dioxide across their body surface but that as organisms increase in size and their SA/V ratio decreases, they need adaptations at their gas exchange surfaces to be able to obtain the oxygen to meet their metabolic demands. This leads into the next part of the lesson which describes the roles of the following structures in insects and bony fish: spiracles, tracheae, tracheoles and tracheole fluid operculum, gill arch, gill filaments and lamellae The next task challenges the students to use their knowledge of topics 1 and 2 to come up with the letters that form the key term, countercurrent flow. This is a key element of the lesson and tends to be a principle that is poorly understood, so extra time is taken to explain the importance of this mechanism. Students are shown two diagrams, where one contains a countercurrent system and the other has the two fluids flowing in the same direction, and this is designed to support them in recognising that this type of system ensures that the concentration of oxygen is always higher in the oxygenated water than in the blood in the lamellae. The final part of the lesson describes the role of the stomata and the mesophyll cells in the gas exchange of a dicotyledonous plant. Students will learn that guard cells contain chloroplasts which generate ATP and then they are challenged to order a series of statements to form a description of the events that result in the opening of the stomata. The differing structures of the spongy mesophyll and palisade mesophyll cells are then considered before the students are challenged to explain how carbon dioxide moves through the leaf after entering via the stomata and then how water vapour and oxygen leave. Clear links are made to the loss of water vapour by transpiration so students are prepared for the lessons covering this biological process later in topic 3.

This lesson describes the principles of ex situ conservation and discusses the advantages and issues surrounding this method. The PowerPoint and accompanying worksheet are part of the second lesson in a series of 2 which have been designed to cover the content of point 3.3 (iii) of the Edexcel A-level Biology B specification and it closely ties in with the previous lesson on in situ conservation. To enrich their understanding of ex situ conservation, the well-known examples of ZSL London zoo, Kew Gardens and the Millennium Seed Bank Project in Wakehurst are used. Students will understand how conserving animal species outside of their natural habitat enables human intervention that ensures the animals are fed and given medical assistance when needed as well as reproductive assistance to increase the likelihood of the successful breeding of endangered species. As with the in situ method in the previous lesson, the issues are also discussed and there is a focus on the susceptibility of captive populations to diseases as a result of their limited genetic diversity. The final part of the lesson considers how seed banks can be used to ensure that plant species avoid extinction and how the plants can be bred asexually to increase plant populations quickly.

This lesson describes and discusses the different methods of protecting endangered species. The engaging PowerPoint and accompanying worksheets have been designed to cover point 18.3 [c] of the CIE A-level Biology specification and the methods described include zoos, botanic gardens, national parks, marine conservation zones and seed banks Hours of research has gone into the planning of this lesson to source interesting examples that increase the relevance of the biological content concerning in situ conservation, and these include the Lizard National Nature Reserve in Cornwall, the Lake Télé Community reserve in the Republic of Congo and the marine conservation zone in the waters surrounding Tristan da Cunha. Students will learn how this form of active management conserves habitats and species in their natural environment, with the aim of minimising human impact whilst maintaining biodiversity. The main issues surrounding this method are discussed, including the fact that the impact of this conservation may not be significant if the population has lost much of its genetic diversity and that despite the management, the conditions that caused the species to become endangered may still be present. A number of quick quiz competitions are interspersed throughout the lesson to introduce key terms and values in a fun and memorable way and one of these challenges them to use their knowledge of famous scientists to reveal the surname, Fossey. Dian Fossey was an American conservationist and her years of study of the mountain gorillas is briefly discussed along with the issue that wildlife reserves can draw poachers and tourists to the area, potentially disturbing the natural habitat. To enrich their understanding of ex situ conservation, the better known examples of ZSL London zoo, Kew Gardens and the Millennium Seed Bank Project in Wakehurst are used. Students will understand how conserving animal species outside of their natural habitat enables human intervention that ensures the animals are fed and given medical assistance when needed as well as reproductive assistance to increase the likelihood of the successful breeding of endangered species. As with the in situ method, the disadvantages are also discussed and there is a focus on the susceptibility of captive populations to diseases as a result of their limited genetic diversity. The final part of the lesson considers how seed banks can be used to ensure that plant species avoid extinction and how the plants can be bred asexually to increase plant populations quickly. Due to the extensiveness of this lesson, it is estimated that it will take in excess of 2/3 hours of allocated A-level teaching time to cover the tasks and content that is included in the lesson.

This lesson describes the reasons for the need to maintain biodiversity, which include those which are ecological, economic and aesthetic. The PowerPoint and accompanying resources have been designed to cover point 18.3 (b) of the CIE A-level Biology specification. Many hours of research have gone into the planning of the lesson so that interesting examples are included to increase the relevance of the multitude of reasons to maintain biodiversity. These include the gray wolves and beavers of Yellowstone National Park and the Za boabab in the Madagascar rainforests as examples of keystone species. Students will learn that these species have a disproportionate effect on their environment relative to their abundance and exam-style questions and guided discussion periods are used to challenge them to explain their effect on other species in the habitat. The CIE exams have a heavy mathematical content and this is reflected in this lesson as students are challenged to complete a range of calculations to manipulate data to support their biological-based answers. All of the exam questions that are included throughout the lesson have mark schemes embedded into the PowerPoint to allow the students to assess their progress. Moving fowards, the economic ans aesthetic reasons to maintain biodiversity are considered, and there is a focus on the soil depletion that occurs when a continuous monoculture is used. The 1 Billion tree scheme that began in New Zealand in 2018 is introduced and the reasons that some groups of people are objecting to what they consider to be a pine monoculture are discussed. Students will recognise that the clear felling of the trees dramatically changes the landscape and that the increased runoff that results can have catastrophic affects for both aquatic life and for humans with floods. A number of quiz competitions are included in the lesson to introduce key terms in a fun and memorable way and some of the worksheets have been differentiated to allow students of differing abilities to access the work

This lesson describes the meaning of the term stem cell and the differences between totipotent, pluripotent and multipotent stem cells. The PowerPoint and accompanying worksheets have been designed to cover points 7.3 (i) and (ii) of the Edexcel A-level Biology B specification meaning that this lesson also contains discussion periods about the potential opportunities to use stem cells from embryos in medicine. The lesson begins with a knowledge recall of the structure of eukaryotic cells and the students have to use the first letters of each of the four answers to reveal the key term, stem cell. Time is then taken to consider the meaning of cellular differentiation, and this leads into the key idea that not all stem cells are equal when it comes to the number of cell types that they have the potential to differentiate into. A quick quiz round introduces the five degrees of potency, and then the students are challenged to use their understanding of terminology to place totipotency, pluripotency, multipotency, oligopotency and unipotency in the correct places on the potency continuum. Although the latter two do not have to be specifically known based on the content of specification point 7.3 (i), an understanding of their meaning was deemed helpful when planning the lesson as it should assist with the retention of knowledge about totipotency, pluripotency and multipotency. These three highest degrees of potency are the main focus of the lesson, and key details are emphasised such as the ability of totipotent cells to differentiate into any extra-embroyonic cell, which the pluripotent cells are unable to do. The morula, and inner cell mass and trophoblast of the blastocyst are used to demonstrate these differences in potency. The final part of the lesson discusses the decisions that the scientific community have to make about the use of pluripotent embryonic stem cells, adult stem cells and also multipotent foetal stem cells As there is a heavy mathematical content in the current A-level Biology exams, a Maths in a Biology context question is included in the lesson (when introducing the morula) to ensure that students continue to be prepared for the numerous calculations that they will have to tackle in the terminal exams. This resource has been differentiated two ways to allow students of differing abilities to access the work

This lesson describes how the standard deviation and the t-test are used to analyse data. The detailed PowerPoint and accompanying resources are part of the first lesson in a series of 2 lessons that have been designed to cover point 10.1 (vi) of the Edexcel A-level Biology B specification. The next lesson, which uses skills covered in this lesson and has also been uploaded, describes how to analyse data using the Spearman rank correlation coefficient A step by step guide walks the students through each stage of the calculation of the standard deviation and gets them to complete a worked example with the class before applying their knowledge to another set of data. This data looks at the birth weights of humans on one day in the UK and this is used again later in the lesson to compare against the birth weights of babies in South Asia when using the student’s t-test. The null hypothesis is re-introduced, as it will encountered when considering the chi squared test in topic 8, and students will learn to accept or reject this based upon a comparison of their value against one taken from the table based on the degrees of freedom.