This lesson describes how an increased carbon dioxide concentration affects the dissociation of oxyhaemoglobin, the Bohr effect. The PowerPoint and accompanying resources have been designed to cover the second part of point 4.5 (i) of the Edexcel A-level Biology B specification and continually ties in with the previous lesson on the role of haemoglobin and dissociation curves. The lesson begins with a terminology check to ensure that the students can use the terms affinity, oxyhaemoglobin and dissociation. In line with this, they are challenged to draw the oxyhaemoglobin dissociation curve and are reminded that this shows how oxygen associates with haemoglobin but how it dissociates at low partial pressures. Moving forwards, a quick quiz is used to introduce Christian Bohr and the students are given some initial details of his described effect. This leads into a series of discussions where the outcome is the understanding that an increased concentration of carbon dioxide decreases the affinity of haemoglobin for oxygen. The students will learn that this reduction in affinity is a result of a decrease in the pH of the cell cytoplasm which alters the tertiary structure of the haemoglobin. Opportunities are taken at this point to challenge students on their prior knowledge of protein structures as well as the bonds in the tertiary structure. The lesson finishes with a series of questions where the understanding and application skills are tested as students have to explain the benefit of the Bohr effect for an exercising individual.

This fully-resourced lesson describes the three main stages of the Calvin cycle as fixation, reduction and regeneration. The detailed PowerPoint and accompanying resources have been designed to cover the content of point 13.1 (g) of the CIE A-level Biology specification and detailed planning ensures that continual links are made to the previous lesson on the light-dependent stage so that students understand how the products of that stage, ATP and reduced NADP, are essential for the Calvin cycle The lesson begins with an existing knowledge check where the students are challenged to recall the names of structures, substances and reactions from the light-dependent stage in order to reveal the abbreviations of the main 3 substances in the Calvin cycle. This immediately introduces RuBP, GP and TP and students are then shown how these substances fit into the cycle. The main section of the lesson focuses on the three phases of the Calvin cycle and time is taken to explore the key details of each phase and includes: The role of RuBisCO in carbon fixation The role of the products of the light-dependent stage, ATP and reduced NADP, in the reduction of GP to TP The use of the majority of the TP in the regeneration of RuBP A step-by-step guide, with discussion points where the class are given time to discuss the answer to selected questions, is used to show how 6 turns of the cycle are needed to form the TP that will then be used to synthesise 1 molecule of glucose. A series of exam-style questions are included at appropriate points of the lesson and this will introduce limiting factors as well as testing their ability to answer questions about this stage when presented with an unfamiliar scientific investigation. The mark schemes are included in the PowerPoint so students can assess their understanding and any misconceptions are immediately addressed.

This lesson describes the structure of enzymes and explains how their specificity enables them to act as catalysts intracellularly and extracellularly. The engaging PowerPoint and accompanying resources have been designed to cover points 1.5 (i), (ii), (iii) & (vii) of the Edexcel A-level Biology B specification and describes 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 topic 1.3 where protein structure and globular proteins were covered. 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, DNA helicase and DNA polymerase and students are challenged on their recall of DNA replication with an exam question before they are challenged on their knowledge of carbohydrates, lipids and proteins from topics 1.1 - 1.3 as they have to recognise some extracellular digestive enzymes from descriptions of their substrates.

This fully-resourced lesson describes how the autonomic nervous system controls the heart rate. The engaging and detailed PowerPoint and accompanying resources have been designed to cover point 9.8 (i) of the Edexcel A-level Biology B specification which states that students should understand the roles of baroreceptors, chemoreceptors, the cardiac centre in the medulla oblongata and the sympathetic and parsympathetic nerves in the control. 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 lesson describes how the role of carrier of proteins and ATP in active transport and the co-transport of sodium ions and glucose in the ileum. The PowerPoint and accompanying resources are part of the final lesson in a series of 3 that have been designed to cover the details of point 2.3 of the AQA A-level Biology specification and also includes descriptions of endocytosis and exocytosis The start of the lesson focuses on the structure of this energy currency and challenges the students prior knowledge as they covered ATP in topic 1.6. As a result, they will recall that this molecule consists of adenine, ribose and three phosphate groups and that in order to release the stored energy, ATP must be hydrolysed. Time is taken to emphasise the key point that the hydrolysis of ATP can be coupled to energy-requiring reactions and this leads into a series of exam-style questions where students are challenged on their knowledge of simple and facilitated diffusion to recognise that ATP is needed for active transport. These questions also challenge them to compare active transport against the forms of passive transport and to use data from a bar chart to support this form of transport. In answering these questions they will discover that carrier proteins are specific to certain molecules and time is taken to look at the exact mechanism of these transmembrane proteins. A quick quiz round introduces endocytosis and the students will see how vesicles are involved along with the energy source of ATP to move large substances in or out of the cell. The students are then shown how exocytosis is involved in a synapse and in the release of ADH from the pituitary gland during osmoregulation which they will cover in later topics. The final part of the lesson describes the movement of sodium ions and glucose from the ileum to the epithelial cells to the blood using a range of proteins which includes cotransporter proteins and students will learn that similar mechanisms are seen in the phloem and in the proximal convoluted tubule.

This lesson describes how individuals may develop immunity, focusing on the different types that are active, passive, natural and artificial. The engaging PowerPoint and accompanying resources have been designed to cover point 6.1 of the Edexcel International A-level Biology specification and there is also a description and discussion of herd immunity to increase the relevance to the current epidemic with COVID-19. The lesson begins with a series of exam-style questions which challenge the students to demonstrate and apply their understanding of the immune response as covered in the previous lessons in this topic. In answering and assessing their answers to these questions, the students will recognise the differences between the primary and secondary immune responses and then a discussion period is included to encourage them to consider how the production of a larger concentration of antibodies in a quicker time is achieved. The importance of antibodies and the production of memory cells for the development of immunity is emphasised and this is continually referenced as the lesson progresses. The students will learn that this response of the body to a pathogen that has entered the body through natural processes is natural active immunity. Moving forwards, time is taken to look at vaccinations as an example of artificial active immunity. Another series of questions focusing on the MMR vaccine will challenge the students to explain how the deliberate exposure to antigenic material activates the immune response and leads to the retention of memory cells. A quick quiz competition is used to introduce the variety of forms that the antigenic material can take along with examples of diseases that are vaccinated against using these methods. The eradication of smallpox is used to describe the concept of herd immunity and the students are given time to consider the scientific questions and concerns that arise when the use of this pathway is a possible option for a government. The remainder of the lesson looks at the different forms of passive immunity and describes the drawbacks in terms of the need for a full response if a pathogen is re-encountered.

This fully-resourced lesson describes the differences between the roles of the B cells and T cells in the body’s immune response. The PowerPoint and accompanying resources have been designed to cover points 6.9 & 6.10 in unit 4 of the Edexcel International A-level Biology specification and includes descriptions of the role of the antigens and the production of antibodies by plasma (effector) cells In the previous lesson on the non-specific responses, the students were introduced to macrophages and dendritic cells as antigen-presenting cells and the start of this lesson challenges their recall and understanding of this process. Time is taken to discuss how the contact between these cells and lymphocytes is critical for the initiation of the body’s (specific) immune response. Moving forwards, a quick quiz competition is used to introduce the names of the different T cells that result from differentiation. Their specific roles are described including an emphasis on the importance of the release of cytokines in cell signalling to activate other immune system cells. T memory cells are also introduced so that students can understand their role in immunological memory and active immunity as described in an upcoming lesson. The next part of the lesson focuses on the B cells and describes how clonal selection and clonal expansion results in the formation of memory B cells and effector cells. A series of understanding and application questions are then used to introduce the structure of antibodies and to explain how the complementary shape of the variable region allows the antigen-antibody complex to be formed. The lesson concludes by emphasising that the pathogen will be overcome as a result of the combination of the actions of phagocytes, T killer cells and the antibodies released by the effector cells

This fully-resourced lesson describes how vaccinations are used to control disease and how immunity can be natural, artifical, active and passive. The engaging PowerPoint and accompanying resources have been designed to cover points 6.7 (v) & (vi) of the Edexcel A-level Biology B specification and there is also a description and discussion on the development of herd immunity. The previous lesson finished with a series of exam questions where students observed differences between the primary and secondary immune responses so the start of this lesson uses an imaginary game of TOP TRUMPS to challenge them on the depth of their understanding. This will act to remind them that a larger concentration of antibodies is produced in a quicker time in the secondary response. The importance of antibodies and the production of memory cells for the development of immunity is emphasised and this will be continually referenced as the lesson progresses. The students will learn that this response of the body to a pathogen that has entered the body through natural processes is natural active immunity. Moving forwards, time is taken to look at vaccinations as an example of artificial active immunity. Another series of questions focusing on the MMR vaccine will challenge the students to explain how the deliberate exposure to antigenic material activates the immune response and leads to the retention of memory cells. A quick quiz competition is used to introduce the variety of forms that the antigenic material can take along with examples of diseases that are vaccinated against using these methods. The eradication of smallpox is used to describe the concept of herd immunity and the students are given time to consider the scientific questions and concerns that arise when the use of this pathway is a possible option for a government. The remainder of the lesson looks at the different forms of passive immunity and describes the drawbacks in terms of the need for a full response if a pathogen is re-encountered.

This fully-resourced lesson introduces bacteriostatic and bactericidal antibiotics and describes their differences, focusing on their modes of action. The engaging PowerPoint and accompanying resources have been designed to cover point 6.14 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification but also makes continual links to earlier lessons in topic 6 as well as related topics from the previous year such as protein synthesis from topic 2 The lesson begins by challenging the students to use their knowledge of the previous topic 6 lessons to identify the suffixes cidal and static. Students will learn that when the prefix is added, these form the full names of two types of antibiotics. Their understanding of terminology is tested further as they have to recognise that Polymyxin B is an example of a bactericidal antibiotic as its actions would result in the death of the bacterial cell. Tetracycline is used as the example of a bacteriostatic antibiotic and students will discover that its prevention of the binding of tRNA that inhibits protein synthesis and this reduction and stopping of growth and reproduction is synonymous with these drugs. Students are challenged on their knowledge of translation and will also be given time for a class discussion to understand that these antibiotics encourage the body’s immune system to overcome the pathogen in natural, active immunity. The final part of the lesson uses a quick quiz competition and a series of exam-style questions to ensure that students can recognise the different antibiotics from descriptions.

This fully-resourced lesson describes the structure and general properties of slow and fast skeletal muscle fibres. The detailed PowerPoint and accompanying resources are the second in a series of 2 lessons that cover the content detailed in point 6.3 of the AQA A-level Biology specification and due to the obvious links, this lesson also challenges the students on their knowledge of respiration, cell structures and biological molecules like glycogen and haemoglobin The following structure and properties are covered over the course of this lesson: Reliance on the aerobic or anaerobic pathways to generate ATP Resistance to fatigue mitochondrial density capillary density myoglobin content (and colour) fibre diameter phosphocreatine content glycogen content A wide variety of tasks are used to cover this content and include knowledge recall and application of knowledge exam-style questions with fully-displayed mark schemes as well as quick quiz competitions to maintain motivation and engagement. This lesson has been specifically planned to tie in with the previous lesson in topic 6.3, titled “Contraction of skeletal muscles”, and this lesson has been uploaded for free

This fully-resourced lesson describes the structure of the human retina and explains how the rhodopsin in rod cells allows vision in low light intensity. The detailed PowerPoint and accompanying resources have been designed to cover points 9.7 (i), (ii) & (iii) of the Edexcel A-level Biology B specification but also makes links to previously covered topics such as cell structure and nervous transmission. 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 in topic 9.5, 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. Cone cells are also introduced, with the main focus being their distribution in the centre of the fovea which is used to explain colour vision in bright light.

This fully-resourced lesson uses real-life examples in plants and animals to explain why cellular respiration is so important. The PowerPoint and accompanying resources have been designed to cover point 5.2.2 (a) of the OCR A-level Biology A specification but can also be used as a revision tool to challenge the students on their knowledge of active transport, nervous transmission and muscle contraction. As the first lesson in this module, it has been specifically planned to act as an introduction to this cellular reaction and provides important details about glycolysis, the Krebs cycle and oxidative phosphorylation that will support the students to make significant progress when these stages are covered during individual lessons. Students met phosphorylation in module 5.2.1 when considering the light-dependent reactions of photosynthesis and their knowledge of the production of ATP in this plant cell reaction is called on a lot in this lesson to show the similarities. The students are also tested on their recall of the structure and function of ATP, as covered in module 2.1.3, through a spot the errors task. By the end of the lesson, the students will be able to explain why the ATP produced in cellular respiration is needed by root hair cells, by companion cells and in the selective reabsorption of glucose in the proximal convoluted tubule. They will also be able to name and describe the different types of phosphorylation and will know that ATP is produced by substrate-level phosphorylation in glycolysis and the Krebs cycle and by oxidative phosphorylation in the final stage of aerobic respiration with the same name.

This fully-resourced lesson looks at the use of electrocardiograms to aid the diagnosis of abnormal heart rhythms. The engaging PowerPoint and accompanying resources have been designed to cover point 7.12 (iii) of the Edexcel International A-level Biology specification but also can be used as a revision lesson as the students are challenged on their prior knowledge of the cardiac cycle and heart structure as covered in topic 1. The lesson has been written to take place in an imaginary cardiology ward where the students are initially challenged on their knowledge of the symptoms and risk factors of CVD before looking at testing through the use of ECGs and diagnosis. The main focus of the lesson is the ECG and a quiz competition is used to introduce the reference points of P, QRS and T before time is taken to explain their representation with reference to the cardiac cycle. Moving forwards, a SPOT the DIFFERENCE task is used to challenge the students to recognise differences between sinus rhythm and some abnormal rhythms including tachycardia and atrial fibrillation. Bradycardia is used as a symptom of sinus node disfunction and the students are encouraged to discuss this symptom along with some others to try to diagnose this health problem. This lesson has been designed to tie in with the lesson that covers the previous specification point on the normal electrical activity of the heart and the myogenic nature of cardiac muscle

This lesson describes the structure and functions of the sensory, relay and motor neurones. The engaging PowerPoint and accompanying resources have been designed to cover point 8.1 of the Edexcel International A-level Biology specification but also considers the organisation of the nervous system into the central and peripheral nervous systems and therefore also covers point 8.10. The PowerPoint has been designed to contain a wide range of activities that are interspersed between understanding and prior knowledge checks that allow the students to assess their progress on the current topics as well as challenge their ability to make links to topics from earlier in the modules. Quiz competitions like SAY WHAT YOU SEE are used to introduce key terms in a fun and memorable way. The students will be able to compare these neurones based on their function but time is taken to distinguish between them based on their structural features. The importance of the myelin sheath for the sensory and motor neurones is briefly discussed and students are introduced to key terminology such as saltatory conduction and Schwann cells so they are prepared for the upcoming lesson covering specification point 8.5. The final task involves a comparison between the three neurones to check that the students have understood the structures and functions of the neurones. Throughout the lesson, the organisation of the nervous system is discussed and students are provided with additional knowledge such as the differences between somatic and autonomic motor neurones.

This lesson describes how the nervous system detects stimuli, focusing on the detection of light by the rods in the the retina of mammals. The PowerPoint has been designed to cover the content of specification point 8.8 of the Edexcel International A-level Biology specification and includes descriptions of the roles of rhodopsin, opsin, retinal, sodium ions, cation channels and hyperpolarisation in the formation of action potentials in the optic neurones. The lesson begins by using a quiz to get the students to recognise the range of stimuli which can be detected by receptors. This leads into a task where the students have to form 4 sentences to detail the stimuli which are detected by certain receptors and the energy conversion that happen as a result. Students will be introduced to the idea of a transducer and learn that receptors always convert to electrical energy which is the generator potential. It is likely that students will be aware that the human retina contains rod and cone cells, so the next part of the 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. The remainder of the lesson focuses on the Pacinian corpuscle and describes how this responds to pressure on the skin, resulting in the opening of the sodium channels and the flow of sodium ions into the neurone to cause depolarisation

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.