This lesson guides students through the stages of the nitrogen cycle, focusing on the vital roles performed by microorganisms in this cycle. The detailed PowerPoint and accompanying resources are part of the 1st lesson in a series of 3 lessons which have been planned to cover point 5.4 (nutrient cycles) of the AQA A-level biology specification. The lesson begins by challenging students to recall two monomers containing nitrogen that were met in topic 1, allowing them to recognise that this chemical element is a key component of nucleotides in DNA and amino acids, which are needed to synthesise proteins. Moving forwards, they will learn that despite the high % of nitrogen in the Earth’s atmosphere, it cannot be used directly by plants, and therefore plants need a supply of “fixed” nitrogen. A diagram is constantly updated and displayed as new information is introduced and this supports their understanding. The students will discover that microorganisms are involved in nitrogen fixation, decomposition and ammonification, nitrification, and denitrification. As each of these biological actions is introduced, time is spent considering key details and understanding checks are used to allow the students to assess their progress. There are also several prior knowledge checks, where students are encouraged to make links to content met in topics 1 - 4. Answers to all questions are embedded into the PowerPoint.

This extensive lesson describes the structure of the human brain and the functions of its parts. The engaging PowerPoint and accompanying resources have been designed to be in line with point 5.1.5 (h) of the OCR A-level biology A specification and therefore covers the gross structure of the human brain and the function of the cerebrum, cerebellum, medulla oblongata, hypothalamus and the pituitary gland. The lesson begins with a knowledge recall challenge, where the students have to complete the diagram showing the organisation of the nervous system, as covered in the previous lesson. This reminds them that the brain is part of the CNS and also reintroduces the autonomic nervous system which will be useful when describing the medulla oblongata. As this is an extensive lesson covering a lot of detail, it has been planned to contain 5 quiz rounds as part of a competition which will help to maintain engagement whilst checking on their recall and understanding of content. There are also multiple understanding and prior knowledge checks which allow the students to assess their progress against the current topic and to make links to previously covered content. All answers to these knowledge checks are embedded into the PowerPoint. The lesson describes the structure of the cerebrum as two hemispheres and then considers the localisation of function of the 4 lobes of the cerebral cortex. It moves onto the cerebellum, focusing on its role of perfecting and coordinating movement, and explains how this is achieved through neural connections with the cerebrum. The control of heart rate by the medulla oblongata is described before the lesson concludes with an exploration of the connections between the hypothalamus and the two lobes of the pituitary gland, specifically in the mechanisms of osmoregulation and thermoregulation. Two of the worksheets have been modified to allow students of different understanding levels to access the work. It is likely that this lesson will take between 2 - 3 hours of teaching time, but sections can be edited and removed if the teacher doesn’t want to look at a particular structure in that detail at this stage of study.

This lesson uses a 10 question multiple-choice assessment to provide students with the opportunity to assess their knowledge of neuronal communication. Module 5.1.3 of the OCR A-level biology A specification covers the role of mammalian sensory receptors, the structure and function of neurones, the generation and transmission of nerve impulses and the structure and roles of synapses and these 10 questions attempt to challenge their overall understanding of this content. The lesson also includes a PowerPoint with the answers to the questions and also further understanding checks to challenge knowledge not directly covered by the multiple-choice assessment. There are also some prior knowledge checks and links to the future.

This lesson describes the course of events that lead to atherosclerosis and explains how the human body can be affected by this inflammatory disease. The engaging PowerPoint and accompanying resources have been planned to cover the content of point 1.10 of the Edexcel International A-level biology specification and therefore includes descriptions of endothelial dysfunction, plaque formation and raised blood pressure. The lesson begins with a task where the students have to use their knowledge of the numbers associated with biology to move forwards and backwards through the alphabet to reveal the name of the disease, atherosclerosis. Students will learn that this is a chronic inflammatory disease. As shown in the cover image, the main part of the lesson uses a step-by-step guide to go through the events, from endothelium damage, monocyte recruitment, macrophage differentiation and eventually the protrusion of plaques into the lumen of the artery. Understanding and prior knowledge checks and quiz quiz competitions are used during this section of the lesson to allow the students to assess their progress and to introduce key terms in a memorable fashion. All answers to any questions are embedded into the PowerPoint. The final part of the lesson uses a series of exam-style questions to consider how atherosclerosis in different blood vessels could lead to medical issues such as myocardial infarctions and strokes.

This lesson describes the nervous pathways of a range of reflex actions, including spinal reflex arcs and a cranial reflex, and their survival value is explored. The PowerPoint and accompanying resources have been planned to cover the content of point 5.1.5 (i) of the OCR A-level biology A specification. The lesson begins with a challenge, where the students have to spot the connections between 3 groups of 3 terms, and this will introduce different neurones, muscle tissues and reflexes for reference throughout. There are prior knowledge checks throughout the lesson, and one is immediately used to check on the students’ knowledge of the functions of the different structures in a nervous pathway and the order they are involved. The spinal reflex after an individual presses on a sharp pin is used to check that they can apply their knowledge to a real biological example. At this point, the potential for a reflex to be overridden if an unmyelinated relay neurone is involved is introduced and this is explained in detail later in the lesson. The knee jerk reflex is then discussed and students will understand that this is the choice for a reflex test because of the direct communication between the sensory and motor neurone. The final part of the lesson describes the corneal reflex as a cranial reflex and students will learn how it can be inhibited through conscious control by the higher part of the brain, as happens when an individual puts contact lenses on.

This lesson describes the differences between skeletal, smooth (involuntary) and cardiac muscle. The PowerPoint and accompanying resources form part of the 1st lesson in a series of 3 lessons which have been planned to cover the content of point 5.1.5 (l) (i) of the OCR A-level biology A specification. The other two lessons are “neuromuscular junctions” and “the sliding filament model of muscular contraction”. The lesson begins with a bit of fun by challenging the students to identify the prep room skeleton from a description and then to recognise that the reason the skeleton doesn’t have free movement or locomotion is because “he” lacks muscles. More specifically, it is the lack of skeletal muscles which prevents bones from moving and this leads into the introduction of this type of muscle tissue as being attached to bones. Time is taken to consider tendons, and more specifically the protein collagen, and students are challenged on their recall of this fibrous protein from module 2.1.2. This lesson contains numerous prior knowledge checks like this, to encourage them to identify the links between topics and modules. All answers to these prior knowledge and understanding checks are embedded into the PowerPoint to allow the students to assess their progress. The structure of skeletal muscle is covered in the 3rd lesson in this series, but this lesson does focus on the structural and functional differences between smooth and cardiac muscle. Students are introduced to intercalated discs and gap junctions in cardiac muscle and are challenged to explain how these features support the stages of the cardiac cycle. Earlier in this module, they covered the regulation of heart rate and a SPOT THE ERRORS task will challenge the detail of their knowledge of this control system. The remainder of the lesson focuses on smooth muscle, using examples in the gut wall, iris and arterial walls to increase relevance.

This fully-resourced lesson looks at the internal and external structure of the mammalian heart and uses the human heart to represent this anatomy. The engaging and detailed PowerPoint and accompanying resources have been designed to cover point 3.1.2 (e) (i) of the OCR A-level Biology A specification As this topic was covered at GCSE, the lesson has been planned to build on this prior knowledge whilst adding the key details which will enable students to provide A-level standard answers. The primary focus is the identification of the different structures of the heart but it also challenges their ability to recognise the important relationship to function. For example, time is taken to ensure that students can explain why the atrial walls are thinner than the ventricular walls and why the right ventricle has a thinner wall than the left ventricle. Opportunities are taken throughout the lesson to link this topic to the others found in topic 3.1.2 including those which have already been covered like circulatory systems as well as those which are upcoming such as the initiation of heart action. There is also an application question where students have to explain why a hole in the ventricular septum would need to be repaired if it doesn’t naturally close over time.

This fully-resourced lesson describes genetic biodiversity as the number of genes in a population and considers how it can be assessed. The engaging PowerPoint and accompanying differentiated resources have been primarily designed to cover point 4.2.1 (e) of the OCR A-level Biology A specification but also introduces inheritance and codominance so that students are prepared for these genetic topics when they are covered in module 6.1.2 In order to understand that 2 or more alleles can be found at a gene loci, students need to be confident with genetic terminology. Therefore the start of the lesson focuses on key terms including gene, locus, allele, recessive, genotype and phenotype. A number of these will have been met at GCSE, as well as during the earlier lessons in module 2.1.3 when considering meiosis, so a quick quiz competition is used to check on their recall of the meanings of these terms. The CFTR gene is then used as an example 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). Two calculations are provided to the students that can calculate the % of loci with more than one allele and the proportion of polymorphic gene loci. At this point, the students are introduced to codominance and again they are challenged to apply their understanding to a new situation by working out the number of phenotypes in the inheritance of blood groups. The lesson concludes with a brief consideration of the HLA gene loci, which is the most polymorphic loci in the human genome, and students are challenged to consider how this sheer number of alleles can affect the chances of tissue matches in organ transplantation

This fully-resourced lesson describes the relationship between the structure, properties and functions of triglycerides in living organisms. The engaging PowerPoint and accompanying worksheets have been designed to cover the first part of point (f) as detailed in AS unit 1, topic 1 of the WJEC A-level Biology specification and links are also made to related future topics such as the importance of the myelin sheath for the conduction of an electrical impulse which is covered in A2. The lesson begins with a focus on the basic structure and roles of lipids, including the elements that are found in this biological molecule and some of the places in living organisms where they are found. Moving forwards, the students are challenged to recall the structure of the carbohydrates from earlier in topic 1 so that the structure of a triglyceride can be introduced. Students will learn that this macromolecule is formed from one glycerol molecule and three fatty acids and have to use their understanding of condensation reactions to draw the final structure. Time is taken to look at the difference in structure and properties of saturated and unsaturated fatty acids and students will be able to identify one from the other when presented with a molecular formula. The final part of the lesson explores how the various properties of a triglyceride mean that it has numerous roles in organisms including that of an energy store and source and as an insulator of heat and electricity.

This fully-resourced lesson describes the light-dependent stage, including the production of ATP by cyclic and non-cyclic photophosphorylation. The detailed PowerPoint and accompanying resources have been designed to cover specification points 5.7 (ii) & (iii) of the Edexcel A-level Biology course and has been planned to link with the previous lesson on the structure of the chloroplast and to prepare for the next lesson on the light-independent stage. This is a topic which students tend to find difficult so this lesson has been intricately planned to walk them through each of the key steps of the light-dependent stage. Time is taken to describe the roles of the major protein complexes that are embedded in the thylakoid membrane and this includes the two photosystems, the proton pump and ATP synthase. A series of exam-style questions have been written that link to other biological topics in this course such as cell structure and membrane transport as well as application questions to challenge them to apply their understanding. Some of these resources have been differentiated to allow students of differing abilities to access the work and to be pushed at the same time. Students will learn that there are two pathways that the electron can take from PSI and at the completion of the two tasks which describe each of these pathways, they will understand how ATP is generated in non-cyclic and cyclic fashion. The final task of the lesson asks them to compare these two forms of photophosphorylation to check that they understand when photolysis is involved and reduced NADP is formed. Due to the detail included in this lesson, it is estimated that it will take in excess of 2.5 hours of allocated A-level teaching time to complete.

This fully-resourced lesson describes the light independent reaction of photosynthesis and explains how reduced NADP is used to form a simple sugar. The detailed PowerPoint and accompanying resources have been designed to cover the second part of point 5.1 of the AQA A-level Biology specification and lengthy planning has ensured that links are continually made to the previous lesson on the light-dependent reaction so that students can understand how the products of that stage 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 light-independent stage. 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 selected questions for the class to consider together, 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 has been specifically written to tie in with the previous lessons on the structure of a chloroplast and the light-dependent stage as well as upcoming lesson on limiting factors

This lesson describes the mechanism of breathing, including the roles of the ribcage, intercostal muscles and the diaphragm. The content of the engaging PowerPoint has been designed to cover the details of the fifth part of specification point 3.2 of the AQA A-level Biology specification and introduces the antagonistic interaction of the external and internal intercostal muscles. The lesson begins with a focus on the diaphragm and students will discover that this sheet of muscle is found on the floor of the thoracic cavity. Whilst planning the lesson, it was deemed important to introduce this region of the body at an early stage because the best descriptions will regularly reference the changes seen in this cavity. As the mechanism of inhalation is a cascade of events, the details of this process are covered in a step by step format using bullet points. At each step, time is taken to discuss the key details which includes an introduction to Boyle’s law that reveals the inverse relationship between volume and pressure. It is crucial that students are able to describe how the actions of the diaphragm, external intercostal muscles and ribcage result in an increased volume of the thoracic cavity and a subsequent decrease in the pressure, which is below the pressure outside of the body. At this point, their recall of the structures of the mammalian gas exchange system is tested, to ensure that they can describe the pathway the air takes on moving into the lungs. The remainder of the lesson involves a task which challenges the students to describe exhalation and then the accessory muscles involved in forced ventilation are also considered.

This fully-resourced lesson describes the ultrastructure of a prokaryotic cell and the function of the structures found in these cells. The engaging PowerPoint and accompanying resources have been designed to cover specification point 3.5 (i) & (ii) as detailed in the Edexcel International A-level Biology specification and also compares these cells against the eukaryotic cells that were met in the previous lesson. A clear understanding of terminology is important for A-level Biology so this lesson begins with a challenge, where the students have to recognise a prefix that they believe translates as before or in front of . This leads into the discovery of the meaning of prokaryote as before nucleus and this acts to remind students that these types of cell lack this cell structure. Links to the previous lessons on the eukaryotic cells are made throughout the lesson and at this particular point, the students are asked to work out why the DNA would be described as naked and to state where it will be found in the cell. Moving forwards, the students will discover that these cells also lack membrane bound organelles and a quick quiz competition challenges them to identify the specific structure that is absent from just a single word. In addition to the naked DNA, students will learn that there are also ribosomes in the cytoplasm and will discover that these are smaller than those found in the cytoplasm of an eukaryotic cell (but the same size as those in chloroplasts and mitochondria). The remainder of the lesson focuses on the composition of the cell wall, the additional features of prokaryotic cells such as plasmids and there is also the introduction of binary fission as the mechanism by which these organisms reproduce

This detailed lesson describes the pressure changes that occur during the cardiac cycle and explains how ECG traces can be interpreted. The PowerPoint and accompanying resources have been designed to cover points 4.4 (iii) & (v) of the Edexcel A-level Biology B specification and focuses on the importance of the valves in ensuring unidirectional movement of blood during the cycle. The start of the lesson introduces the cardiac cycle as well as the key term systole, so that students can immediately recognise that the three stages of the cycle are atrial and ventricular systole followed by diastole. Students are challenged on their prior knowledge of the structure of the heart as they have to name and state the function of an atrioventricular and semi-lunar valve from an internal diagram. This leads into the key point that pressure changes in the chambers and the major arteries results in the opening and closing of these sets of valves. Students are given a description of the pressure change that results in the opening of the AV valves and shown where this would be found on the graph detailing the pressure changes of the cardiac cycle. They then have to use this as a guide to write descriptions for the closing of the AV valve and the opening and closing of the semi-lunar valves and to locate these on the graph. By providing the students with this graph, the rest of the lesson can focus on explaining how these changes come about. Students have to use their current and prior knowledge of the chambers and blood vessels to write 4 descriptions that cover the cardiac cycle. The final part of the lesson covers the changes in the volume of the ventricle. The remainder of the lesson focuses on the ECG and explains how these traces can be interpreted to diagnose heart problems. A quiz competition is used to introduce the reference points of P, QRS and T on a normal sinus rhythm 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 describes the meaning of ecological terms and explains how biotic and abiotic factors control the distribution of organisms in a habitat. The engaging PowerPoint and accompanying resources have been designed to cover points 5.11, 5.12 and 5.13 in unit 4 of the Edexcel International A-level Biology (Salters Nuffield) specification and therefore cover the biological definitions of ecosystem, community, population and habitat. A quiz round called REVERSE Biology Bingo runs throughout the lesson and challenges students to recognise the following key terms from descriptions called out by the bingo caller: community ecosystem abiotic factor photosynthesis respiratory substrate biomass calorimetry distribution niche The ultimate aim of this quiz format is to support the students to understand that any sugars produced by photosynthesis that are not used as respiratory substrates are used to form biological molecules that form the biomass of a plant and that this can be estimated using calorimetry. Links are made to photosynthesis and net primary productivity as these will be met later in topic 5 as well as challenging their prior knowledge of adaptations, heterozygosity index classification and biological molecules. The final part of the lesson uses an exam-style question to get the students to recognise that biotic and abiotic factors control the distribution of organisms in a habitat and to recall the concept of niche.

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.