This detailed lesson describes the relationship between the structure and function of starch and cellulose. The engaging PowerPoint and accompanying resource have been designed to cover point 4.9 of the Pearson Edexcel A-level Biology A specification and focuses on the importance of the glycosidic and hydrogen bonds for the structure of these polysaccharides. The structure of amylose and amylopectin was described during a lesson in topic 1, so the start of this lesson challenges the students on their recall of these details. They have to complete a comparison table for these two polysaccharides by identifying the monomer and type of glycosidic bonds that are found in each of the structures. Time is taken to explain how the greater resistance to digestion of amylose means that this carbohydrate is important for plant energy storage whereas the multiple chain ends in the branched amylopectin means that this polysaccharide can be hydrolysed quickly when energy is needed. The rest of the lesson describes the structure of cellulose and focuses on the link between the structure and the need for this polysaccharide to support the plant cell as well as the whole plant. Students will see how every other beta glucose monomer is rotated by 180 degrees and will learn that hydrogen bonds form between these molecules on the same chain as well as between adjacent chains in a cellulose microfibril. The lesson concludes with a quick quiz competition where the students have to compete to open a safe using a combination made up of key values associated with glycogen, starch and cellulose.

This fully-resourced lesson explains how an enzyme’s specificity is related to their 3D structure and enables them to act as biological catalysts. The engaging PowerPoint and accompanying resources have been designed to cover the first parts of specification point 1.4.2 and considers the details of Fischer’s lock and key hypothesis and Koshland’s induced-fit model to deepen student understanding of the mechanism of enzyme action The lesson has been specifically planned to tie in with related topics that were previously covered such as protein structure and globular proteins. This prior knowledge is tested through a series of exam-style questions along with current understanding and mark schemes are included in the PowerPoint so that students can assess their answers. Students will learn that enzymes are large globular proteins which contain an active site that consists of a small number of amino acids. Emil Fischer’s lock and key hypothesis is introduced to enable students to recognise that their specificity is the result of an active site that is complementary in shape to a single type of substrate. Time is taken to discuss key details such as the control of the shape of the active site by the tertiary structure of the protein. The induced-fit model is described so students can understand how the enzyme-susbtrate complex is stabilised and then students are challenged to order the sequence of events in an enzyme-controlled reaction. The lesson finishes with a focus on ATP synthase and DNA polymerase so that students are aware of these important intracellular enzymes when learning about the details of respiration and DNA replication before they are challenged on their knowledge of carbohydrates, lipids and proteins from topics 1.2 - 1.4 as they have to recognise some extracellular digestive enzymes.

This fully-resourced lesson describes the role of barriers in protecting the body from infection by pathogens when entering the body by the major routes. The engaging and detailed PowerPoint and accompanying resources have been designed to cover points 6.11 (i) & (ii) of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification and describe the following barriers: skin key steps of the blood clotting process mucous membranes stomach acid vaginal and skin flora There are clear links to topics 1, 2 and 3 in each of these barriers, so time is taken to consider these during 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 blood clotting, protein structure, key terminology and the epithelium that lines the different parts of the airways. All of the exam-style questions and tasks have mark schemes that are embedded in the PowerPoint and a number of them have been differentiated to allow students of differing abilities to access the work.

This lesson describes how tissue fluid is formed and reabsorbed and also describes the role of the lymphatic system in the return of fluid to the blood. The detailed PowerPoint and accompanying resources have been designed to cover points 4.6 (i & ii) of the Edexcel A-level Biology B specification and explains how a combination of the effects of hydrostatic pressure and oncotic pressure results in the formation of tissue fluid in animals. The lesson begins with an introduction to the arteriole and venule end of a capillary as these will need to be considered as separate entities when describing the formation of tissue fluid. A quick quiz competition introduces a value for the hydrostatic pressure at the arteriole end and students are challenged to first predict some parts of the blood will move out of the capillary as a result of the push from the hydrostatic pressure and this allows oncotic pressure to be initially explored. The main part of the lesson uses a step by step guide to describe how the net movement is outwards at the arteriole end before students will use this guidance to describe what happens at the venule end. In the concluding part of the lesson, students will come to recognise oedema as a condition where tissue fluid accumulates and they again are challenged to explain how this occurs before they finally learn how the fluid is returned to the circulatory system as lymph.

This lesson guides students through the use of the 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 8.2 (vi) of the Edexcel A-level Biology B specification The lesson includes a step-by-step guide to demonstrates how to carry out the test in small sections. 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 is the final lesson of topic 8.2 (transfer of genetic information) and links are made throughout the lesson to earlier parts of this topic such as dihybrid inheritance as well as to earlier topics like meiosis

This detailed lesson describes how changes in ventilation rate are brought about to allow for the delivery of oxygen and the removal of carbon dioxide. The engaging PowerPoint and accompanying resources have been designed to cover the second part of point 7.9 (ii) in the Pearson Edexcel A-level Biology A specification. The previous lesson described the control of heart rate so this lesson has been written to tie in with this and to use this knowledge to further the students understanding of the control of ventilation rate. The lesson begins with a focus on the muscles involved in ventilation, specifically the diaphragm and external intercostal muscles, so that students can understand how their contraction results in an increase in the volume of the thoracic cavity. Boyle’s law is briefly introduced to allow students to recognise the relationship between volume and pressure so that the movement of air with the pressure gradient can be described. Time is then taken to consider the importance of inhalation and an exam-style question challenges the students to explain that a constant supply of oxygen to the alveoli is needed to maintain a steep concentration gradient with the surrounding capillaries. The students are then tasked with writing a description of exhalation at rest using the description of inhalation as their guide. The rest of the lesson focuses on the mechanisms involved in increasing the rate and depth of breathing during exercise. Students will use their knowledge of the control of heart rate to recall that chemoreceptors detect changes in oxygen and carbon dioxide and blood pH and that the medulla oblongata processes the sensory information that it receives before coordinating a response. The final task challenges them to use the information provided in this lesson and the previous one to order 10 detailed descriptions so they can form a complete passage about this control system.

This fully-resourced lesson describes the modes of action of the T and B lymphocytes in the immune response. The detailed PowerPoint and accompanying resources have been designed to cover point 2.4 of the CIE A-level Biology specification and the structure of antibodies and the roles of memory cells is also briefly introduced. Antigen presentation was introduced at the end of the previous lesson so the task at the start of this lesson challenges students to recognise the name of this process and then they have to spot the errors in the passage that describes the details of this event. This reminds them that contact between the APC and T lymphocytes is necessary to elicit a response which they will come to recognise as the cellular response. A series of quick quiz rounds reveals key terms in a memorable way and one that is introduced is helper T cells. Time is then taken to describe the importance of cell signalling for an effective response and students will learn how the release of chemicals by these cells activates other aspects of the response. The role of the killer T cells is also described before an exam-style question is used to check on their understanding at this point of the lesson. This leads into the section of the lesson that deals with the humoral response and students will understand how this involves the antibodies that are produced by the plasma cells that are the result of clonal selection and expansion. The remainder of the lesson focuses on the role of the antibodies and the attachment of phagocytes to opsonins.

This lesson looks at the structure of the DNA that is found in the nucleus, mitochondria and chloroplasts of eukaryotic cells and in prokaryotic cells. Both the engaging PowerPoint and accompanying resources have been designed to cover point 2.1.3 (d)(i) of the OCR A-level Biology A specification. As students will already have some knowledge of this nucleic acid from GCSE and from the earlier A-level topics, the lesson has been written to build on this prior knowledge and then to add key detail. As well as focusing on the differences between the DNA found in these two types of cells which includes the length, shape and association with histones, the various tasks will ensure that students are confident to describe how this double-stranded polynucleotide is held together by hydrogen and phosphodiester bonds. This knowledge of phosphodiester bonds means that specification point 2.1.3 © is also covered during this lesson. These tasks include exam-style questions which challenge the application of knowledge as well as a few quiz competitions to maintain engagement.

This detailed lesson describes the role of the mRNA, tRNA, rRNA and amino acids during the second stage of protein synthesis - translation. Both the PowerPoint and accompanying resources have been designed to cover the second part of point 2.1.3 (g) of the OCR A-level Biology A specification and continually links back to the previous lessons in this module on the structure of DNA and RNA and the genetic code Translation is a topic which is often poorly understood and so this lesson has been written to enable the students to understand how to answer the different types of questions by knowing and including the key details of the structures involved. The lesson begins by challenging the students to consider why it is so important that the amino acids are assembled in the correct order during the formation of the chain. Moving forwards, a quick quiz round called “LOST IN TRANSLATION” is used to check on their prior knowledge of the mRNA strand, the tRNA molecules, the genetic code and the ribosomes. The next task involves a very detailed description of translation that has been divided into 14 statements which the students have to put into the correct order. By giving them a passage that consists of this considerable detail, they can pick out the important parts to use in the next task where they have to answer shorter questions worth between 3 and 4 marks. These types of questions are common in the assessments and by building up through the lesson, their confidence to answer this type should increase. The final two tasks of the lesson involve another quiz, where the teams compete to transcribe and translate in the quickest time before using all that they have absorbed to answer some questions which involve the genetic code and the mRNA codon table

This REVISION resource has been written with the aim of motivating the students whilst they are challenged on their knowledge of the content in Biology TOPIC 8 (Exchange and transport in animals) of the Edexcel GCSE Combined Science specification. The resource contains an engaging and detailed PowerPoint (90 slides) and accompanying worksheets, most of which are differentiated to allow all abilities to access the work. The wide range of activities, which include exam questions and quiz competitions, have been designed to cover as much of topic 8 as possible but the following sub-topics have been given a particular focus: Surface area to volume ratio Gas exchange at the alveoli The structure of the blood vessels The gross structure of the heart and the major blood vessels Calculating the cardiac output The functions of the components of the blood Aerobic vs anaerobic respiration There is a large emphasis on mathematical skills in the new specification and these are tested throughout the lesson. This resource is suitable for use at the end of topic 8, in the lead up to mocks or in the preparation for the final GCSE exams.

This revision resource includes a range of activities that will act to engage and motivate the students whilst they assess their understanding of the Animal nutrition content (topic B6) of the CIE IGCSE Combined Science specification for examination in June and November 2020 and 2021. There are exam questions with explained answers as well as quick tasks and quiz competitions such as “Have you got the right BALANCE” where students are challenged to recognise whether a statement about the balanced diet is accurate or not. The lesson was designed to cover as much content as possible but the following topics have received particular attention: Mechanical digestion Chemical digestion by digestive enzymes Amylase and the break down of starch The adaptations of the small intestine to allow absorption The roles of the hydrochloric acid in gastric juice The break down of lipids in the small intestine The components of a balanced diet This resource includes a detailed and engaging PowerPoint (51 slides) and a worksheet which is differentiated two ways. Efforts have been made to make links to other topics such as enzymes (B4) so students can see the importance of being able to make connections in their answers

An engaging lesson presentation (82 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 C4 (Predicting and identifying reactions and products) of the OCR Gateway A GCSE Chemistry specification. The topics that are tested within the lesson include: Group 1 - the alkali metals Group 7 - the halogens Halogen displacement reactions Group 0 - the noble gases The transition metals Reactivity of elements Detecting gases Detecting cations Students will be engaged through the numerous activities including quiz rounds like “Crack the CODE” and “Blockbusters” whilst crucially being able to recognise those areas which need further attention

This clear and detailed lesson describes the process of oxidative phosphorylation, including the roles of the electron carriers, oxygen and the mitochondrial cristae. The PowerPoint has been designed to cover points 12.2 (f) and (g) of the CIE International A-level Biology specification and includes details of the electron transport system, the flow of protons and ATP synthase. The lesson begins with a discussion about the starting point of the reaction. In the previous stages, the starting molecule was the final product of the last stage but in this stage, it is the reduced coenzymes which release their hydrogen atoms. Moving forwards, the process of oxidative phosphorylation is covered in 7 detailed steps and at each point, key facts are discussed and explored in further detail to enable a deep understanding to be developed. Students will see how the proton gradient across the inner membrane is created and that the flow of protons down the channel associated with ATP synthase results in a conformational change and the addition of phosphate groups to ADP by oxidative phosphorylation. Understanding checks are included throughout the lesson to enable the students to assess their progress and prior knowledge checks allow them to recognise the clear links to other topics and modules. This lesson has been written to tie in with the other uploaded lessons on glycolysis, the Link reaction and the Krebs cycle

This detailed lesson describes the different levels of protein structure and focuses on the bonds that hold these molecules in shape. Both the engaging PowerPoint and accompanying resources have been designed to cover specification point 2.3 (b) of the CIE International A-level Biology course and makes continual links to previous lessons such as amino acids & peptide bonds as well as to upcoming lessons like enzymes and antibodies. The start of the lesson focuses on the formation of a peptide bond during a condensation reaction so that students can understand how a dipeptide is formed and therefore how a polypeptide forms when multiple reactions occur. The main part of the lesson describes the different levels of protein structure. A step by step guide is used to demonstrate how the sequences of bases in a gene acts as a template to form a sequence of codons on a mRNA strand and how this is translated into a particular sequence of amino acids known as the primary structure. The students are then challenged to apply their understanding of this process by using three more gene sequences to work out three primary structures and recognise how different genes lead to different sequences. Moving forwards, students will learn how the order of amino acids in the primary structure determines the shape of the protein molecule, through its secondary, tertiary and quaternary structure and time is taken to consider the details of each of these. There is a particular focus on the different bonds that hold the 3D shape firmly in place and a quick quiz round then introduces the importance of this shape as exemplified by enzymes, antibodies and hormones. Students will see the differences between globular and fibrous protein and again biological examples are used to increase relevance. The lesson concludes with one final quiz round called STRUC by NUMBERS where the students have to use their understanding of the protein structures to calculate a numerical answer.

This REVISION lesson contains an engaging powerpoint (45 slides) and is fully-resourced with associated worksheets. The lesson uses a range of activities which include exam questions (with displayed answers), differentiated tasks and quiz competitions to engage students whilst they assess their knowledge of the content that is found within topics P12 (Magnetism and the motor effect) and P13 (Electromagnetic induction) of the Edexcel GCSE Combined Science specification. Generally, these topics are poorly understood by students but are regularly assessed through questions in the GCSE exams and so time has been taken to design the lesson so that the key points are covered and common misconceptions addressed. The following specification points are covered in this lesson: Recall that unlike magnetic poles attract and like magnetic poles repel Explain the difference between permanent and induced magnets Describe the use of plotting compasses to show the shape and direction of the field of a magnet and the Earth’s magnetic field Explain how the behaviour of a magnetic compass is related to evidence that the core of the Earth must be magnetic Explain that magnetic forces are due to interactions between magnetic fields Recall and use Fleming’s left-hand rule to represent the relative directions of the force, the current and the magnetic field for cases where they are mutually perpendicular Use the equation which connects force on a conductor, magnetic flux density, current and length Recall that a transformer can change the size of an alternating voltage Explain why, in the national grid, electrical energy is transferred at high voltages from power stations, and then transferred at lower voltages in each locality for domestic uses as it improves the efficiency by reducing heat loss in transmission lines Explain where and why step-up and step-down transformers are used in the transmission of electricity in the national grid Use the power equation (for transformers with 100% efficiency) This lesson is suitable for use throughout the duration of the GCSE course, as an end of topic revision lesson or as a lesson in the lead up to mocks or the actual GCSE exams

This is a fully-resourced lesson that covers the content of specification point 15.1 (k) of the CIE International A-level Biology specification which states that students should be able to explain the sliding filament model of muscular contraction. The wide range of activities included in the lesson will engage and motivate the students whilst the understanding and previous knowledge checks will not only allow them to assess their progress but also challenge them to make links to other Biology topics. The start of the lesson is designed to encourage the students to consider how a sarcomere can narrow but the lengths of the myofilaments can remain the same. In doing so, they will be introduced to the idea of the sliding filament model and the main task of the lesson involves the formation of a bullet point description of this model where one event is the trigger for the next. Time is taken during this section to focus on the involvement of the calcium ions but also ATP and the idea of the sources of this molecule, including creatine phosphate, are discussed in more detail later in the lesson. The final part of the lesson involves students having to apply their knowledge by describing the effect on muscle contraction when a part of a structure is unable to function correctly. This lesson has been designed for students studying the CIE International A-level Biology course and ties in well with the other uploaded lessons on this topic, particularly the lesson which covers the ultrastructure of striated muscle

This fully-resourced lesson looks at how heart rate is controlled by the cardiovascular control centre in the medulla oblongata. The engaging and detailed PowerPoint and accompanying resources have been designed to cover the first part of point 7.9 (ii) of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification but also ties in well with previously covered topics and provides a good introduction to control systems which are covered later in topic 7 and 8. 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

This engaging and fully-resourced lesson looks at how genetic drift can arise after a genetic bottleneck or as a result of the Founder effect. The detailed PowerPoint and accompanying resources have been designed to cover point 17.2 © of the CIE International A-level Biology specification which states that students should be able to explain how the Founder effect and genetic drift may affect allele frequencies in populations. A wide range of examples are used to show the students how a population that descends from a small number of parents will have a reduction in genetic variation and a change in the frequency of existing alleles. Students are encouraged to discuss new information to consider key points and understanding checks in a range of forms are used to enable them to check their progress and address any misconceptions. Students are provided with three articles on Huntington’s disease in South Africa, the Caribbean lizards and the plains bison to understand how either a sharp reduction in numbers of a new population beginning from a handful of individuals results in a small gene pool. Links to related topics are made throughout the lesson to ensure that a deep understanding is gained.

This fully-resourced lesson guides students through the use of the Hardy-Weinberg equations to determine the frequency of alleles, genotypes and phenotypes in a population. Both the detailed PowerPoint and differentiated practice questions on a worksheet have been designed to cover point 17.2 (d) of the CIE International A-level Biology specification which states that students should be able to demonstrate and apply their knowledge and understanding of the use of the principle to calculate frequencies in populations. The lesson begins by looking at the two equations and ensuring that students understand the meaning of each of the terms. The recessive condition, cystic fibrosis, is used as an example so that students can start to apply their knowledge and assess whether they understand which genotypes go with which term. Moving forwards, a step-by-step guide is used to show students how to answer a question. Tips are given during the guide so that common misconceptions and mistakes are addressed immediately. The rest of the lesson gives students the opportunity to apply their knowledge to a set of 3 questions, which have been differentiated so that all abilities are able to access the work and be challenged.

This detailed lesson explains how the process of transcription results in the production of messenger RNA (mRNA). Both the detailed PowerPoint and accompanying resource have been designed to specifically cover the first part of point 6.2 (d) of the CIE International A-level Biology specification. The lesson begins by challenging the students to recall that most of the nuclear DNA in eukaryotes does not code for polypeptides. This allows the promoter region and terminator region to be introduced, along with the structural gene. Through the use of an engaging quiz competition, students will learn that the strand of DNA involved in transcription is known as the template strand and the other strand is the coding strand. Links to previous lessons on DNA and RNA structure are made throughout and students are continuously challenged on their prior knowledge as well as they current understanding of the lesson topic. Moving forwards, the actual process of transcription is covered in a 7 step bullet point description where the students are asked to complete each passage using the information previously provided. An exam-style question is used to check on their understanding before the final task of the lesson looks at the journey of mRNA to the ribosome for the next stage of translation. This lesson has been written to challenge all abilities whilst ensuring that the most important details are fully explained.