This lesson describes how to calculate the cardiac output as the product of stroke volume and the heart rate. The PowerPoint and accompanying resource have been designed to cover point 7.13 (i) of the Edexcel International A-level Biology specification. The lesson begins by challenging the students to recognise that the left ventricle has the most muscular wall of all of the heart chambers. This allows the stroke volume to be introduced as the volume of blood ejected from the left ventricle each heart beat and then a quiz competition is used to introduce normative values for the stroke volume and the heart rate. Moving forwards, students will learn that the cardiac output is the product of the stroke volume and the heart rate. A series of exam-style questions will challenge the students to use this formula and to manipulate it and to work out the percentage change. The final part of the lesson looks at the adaptation of the heart to aerobic training in the form of cardiac hypertrophy and then the students are challenged to work out how this would affect the stroke volume, the cardiac output and the resting heart rate.

This fully-resourced lesson describes the major routes that pathogens take when entering the body and the body’s barriers to this infection. The engaging and detailed PowerPoint and accompanying resources have been designed to cover points 6.7 (i) & (ii) of the Edexcel International A-level Biology specification and includes descriptions of the following barriers: skin the blood clotting process mucous membranes stomach acid vaginal acid and flora skin and gut flora wax in the ear canal There are clear links to topics 1, 2 and 3 in each of these barriers, so these are considered and discussed during each of the descriptions. For example, the presence of keratin in the cytoplasm of the skin cells allows the student knowledge of the properties of this fibrous protein to be checked. Other topics that are revisited during this lesson include protein structure, key terminology and the epithelium that lines the different parts of the airways. All of the exam-style questions have mark schemes that are embedded into the PowerPoint and a number of the tasks have been differentiated to allow students of differing abilities to access the work.

This fully-resourced lesson describes the main stages of mitosis and explains the significance of this type of nuclear division in life cycles. The PowerPoint and accompanying resources have been designed to cover points 2.1.6 (c & e) of the OCR A-level Biology A specification and make direct links to the previous lesson which covered the cell cycle 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 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 the characteristic features of the three domains and explains why viruses are not included in this classification. The PowerPoint and accompanying resources have been primarily designed to cover points 18.2 (b) & 18.2 (d) of the CIE A-level Biology specification but also contains tasks that challenge the students on their knowledge of taxonomic hierarchy from this topic and the features of virus from topic 1. The lesson begins with an introduction of the microbiologist Carl 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 the last 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 and will understand that it wasn’t until 13 years after the discovery that it was adopted. Moving forwards, the rest of the lesson explains why viruses are not included in this classification and outlines how they are classified, according to the ICTV, through the type of nucleic acid they contain and whether this is single-stranded or double-stranded

This lesson describes the roles of the buccal cavity, operculum, gill lamellae and countercurrent flow in ventilation and gas exchange in bony fish. The detailed PowerPoint and accompanying resources are part of the first lesson in a series of 2 that have been designed to cover the details of point 3.1.1 (f) of the OCR A-level Biology A specification. The second lesson in this series covers the mechanisms of ventilation and gas exchange in insects. The lesson has been specifically planned to prepare students for the content of module 3.1.2 (Transport in animals) and therefore begins with an introduction and a brief description of the single circulatory system of a fish as this has an impact on the delivery of deoxygenated blood to the lamellae. A quick quiz competition is used to introduce the operculum and then the flow of blood along the gill arch and into the primary lamellae and then into the capillaries in the secondary lamellae is described. The next task challenges the students to use their knowledge of module 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 feature 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 remainder of the lesson focuses on the coordinated movements of the buccal-opercular pump to ensure that the water continues to flow over the gills. Current understanding and prior knowledge checks are included throughout the lesson and students can assess their progress against the mark schemes which are embedded into the PowerPoint

This engaging lesson describes the structures of virus particles and explains why viruses are described as acellular and non-living. The PowerPoint and accompanying resource are part of the second lesson in a series of 2 lessons which have been designed to cover the detail of specification point (b) in AS unit 1, topic 2 of the WJEC A-level Biology specification Details of the COVID-19 epidemic are included in the lesson to increase relevance and to help students to understand this biological topic in greater depth. They will understand that the lack of cell structures results in an acellular classification and the fact that it is unable to reproduce without a host is one of the additional reasons that renders it as non-living. The main focus of the lesson is the nucleic acid, the capsid and the attachment proteins that are present in these microorganisms and time is taken to explain how these structures are involved in the infection of a host cell. The lipid membrane is also introduced and links are made to the previous lessons on eukaryotic cells. The final section uses a version of BBC 1’s POINTLESS to introduce a number of viral diseases in animals and the use of a glycoprotein by HIV to attach to helper T cells is briefly introduced so students are prepared for the immunology option if taken

This lesson describes the ethical and economic reasons for the maintenance of biodiversity. The engaging PowerPoint and accompanying worksheets are filled with real-life biological examples and have been designed to cover point 3.3 (ii) of the Edexcel A-level Biology B 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 latest A-level Biology 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 principles of in situ conservation and considers the benefits as well as the issues that surround this method. The PowerPoint and accompanying resources are part of the first 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. Hours of research have gone into the planning of this lesson to source interesting examples to increase the relevance of the biological content, 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 final issue that wildlife reserves can draw poachers and tourists to the area, potentially disturbing the natural habitat.

This lesson describes the role of the rER and the Golgi apparatus in the formation of proteins, the transport within cells and their secretion. The PowerPoint and accompanying resources have been designed to cover point 3.3 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification and also includes key details about the role of the cytoskeleton in the transport of the vesicles that contain the protein between the organelles and the membrane. The lesson begins with the introduction of the cytoskeleton and explains how this network of protein structures transverses across the cytoplasm and is fundamental to the transport of molecules between organelles. The lesson has been planned to closely tie in with the previous lesson on the ultrastructure of eukaryotic cells and students are challenged on their knowledge of the function of the organelles involved in protein formation (and modification) through a series of exam-style questions. By comparing their answers against the mark scheme embedded in the PowerPoint, students will be able to assess their understanding of the following: Transcription in the nucleus to form an mRNA strand and the exit of this nucleic acid through the nuclear pore Translation at the ribosomes on the surface of the rER to assemble the protein Transport of the vesicles containing the protein to the Golgi apparatus Modification of the protein at the Golgi apparatus Formation of the Golgi vesicle and its transport to the cell membrane for exocytosis Time is taken to discuss the finer details of this process such as the arrival of the vesicle at the cis face and the transport away from the trans face and the requirement of ATP for the transport of the vesicles along the microtubule track and exocytosis. The remainder of the lesson uses a series of exam-style questions about digestive enzymes (extracellular proteins) to challenge the students on their recall of the structure of starch and proteins

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 a range of methods that can be used to assess the distribution and abundance of organisms in a local area. The PowerPoint and accompanying worksheets have been designed to cover points [c] and [d] of topic 18.1 of the CIE A-level Biology specification and describe the use of frame quadrats, line and belt transects, and the mark-release-recapture method. Due to the substantial mathematical content of the A-level Biology exams, as well as descriptions of the different methods, there is a focus on the range of calculations that are used to estimate the population of either sessile or motile species. As shown by the image, step by step guides are used to walk the students through the key stages in these calculations before exam-style questions challenge them to apply their understanding and mark schemes are included in the lesson to allow them to immediately assess their progress. The precautions and assumptions associated with the mark-release-recapture method are discussed and links are made to stabilising selection as covered in topic 17 when considering how the number of species have changed over time.

This lesson describes the concept of homeostasis using negative feedback control and also describes the role of positive feedback. The PowerPoint and accompanying resources have been designed to cover specification points (a & b) in topic 7 of A2 unit 3 of the WJEC A-level Biology specification and explains how this feedback control maintains systems within narrow limits but has also been planned to provide important details for upcoming topics such as osmoregulation. The normal ranges for blood glucose concentration, blood pH and body temperature are introduced at the start of the lesson to allow students to recognise that these aspects have to be maintained within narrow limits. A series of exam-style questions then challenge their recall of knowledge from AS units 1 & 2 and the earlier topics in A2 unit 3 as they have to explain why it’s important that each of these aspects is maintained within these limits. The students were introduced to homeostasis at GCSE, so this process is revisited and discussed, to ensure that students are able to recall that this is the maintenance of a state of dynamic equilibrium. A quick quiz competition is used to reveal negative feedback as a key term and students will learn how this form of control reverses the original change and biological examples are used to emphasise the importance of this system for restoring levels to the limits (and the optimum). The remainder of the lesson explains how positive feedback differs from negative feedback as it increases the original change and the role of oxytocin in birth and the movement of sodium ions into a neurone are used to exemplify the action of this control system.

This lesson guides students through the use of a chi-squared test to determine the significance of the difference between observed and expected results. It is fully-resourced with a detailed PowerPoint and differentiated worksheets that have been designed to cover point (d) in topic 3 of A2 unit 4 of the WJEC A-level Biology specification The lesson includes a step-by-step guide to demonstrates how to carry out the test in small chunks. At each step, time is taken to explain any parts which could cause confusion and helpful hints are provided to increase the likelihood of success in exam questions on this topic. Students will understand how to use the phenotypic ratio to calculate the expected numbers and then how to find the critical value in order to compare it against the chi-squared value. A worked example is used to show the working which will be required to access the marks and then the main task challenges the students to apply their knowledge to a series of questions of increasing difficulty. This lesson has been specifically designed to tie in with the previous lessons in this topic as there are regular references to dihybrid inheritance as well as to topics in the AS units like meiosis