This fully-resourced lesson describes the process of contraction of skeletal muscle in terms of the sliding filament theory. The PowerPoint and accompanying resources have been designed to cover point 7.11 of the Edexcel International A-level Biology specification and includes descriptions of the role of actin, myosin, troponin, tropomyosin, calcium ions, ATP and ATPase. The lesson begins with a study of the structure of the thick and thin filaments. Students will recognise that the protruding heads of the myosin molecule are mobile and this enables this protein to bind to the binding sites when they are exposed on actin. This leads into the introduction of troponin and tropomyosin and key details about the binding of calcium to this complex is explained. Moving forwards, students are encouraged to discuss possible reasons that can explain how the sarcomere narrows during contraction when the filaments remain the same length. This main part of the lesson goes through the main steps of the sliding filament model of muscle contraction and the critical roles of the calcium ions and ATP are discussed. The final task of the lesson challenges the students to apply their knowledge by describing the immediate effect on muscle contraction when one of the elements doesn’t function correctly. This lesson has been written to tie in with the previous lesson on the structure of skeletal muscle fibre (point 7.10)

This lesson describes the role of the cardiovascular control centre in the medulla oblongata in the control of heart rate. The engaging and detailed PowerPoint and accompanying resources have been designed to cover the first part of point 7.13 (ii) of the Edexcel International A-level Biology specification and explains how this regulation enables the rapid delivery of oxygen and the removal of carbon dioxide. 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 reminds students of the meaning of homeostasis and describes the how thermoregulation maintains the body in dynamic equilibrium during exercise. The PowerPoint has been designed to cover point 7.17 of the Edexcel International A-level Biology specification. Students were introduced to homeostasis at GCSE and this lesson has been written to build on that knowledge and to add the key detail needed at this level. Focusing on the three main parts of a homeostatic control system, the students will learn about the role of the internal and peripheral thermoreceptors, the thermoregulatory centre in the hypothalamus and the range of effectors which bring about the responses to restore optimum levels. The following responses are covered in this lesson: Vasodilation Increased sweating Body hairs In each case, time is taken to challenge students on their ability to make links to related topics such as the arterioles involved in the redistribution of blood and the high specific latent heat of vaporisation of water.

This fully-resourced lesson describes how selection pressures act on a gene pool and cause stabilising, directional and disruptive selection. The PowerPoint and accompanying resources have been designed to cover point 8.3 (i) of the Edexcel A-level Biology B specification which states that students should be able to identify each type of selection by its effect on different phenotypes. The lesson begins with an introduction to the mark, release, recapture method to calculate numbers of rabbits with different coloured fur in a particular habitat. This shows changes in numbers of the organisms and sketch graphs are then constructed to show these changes in the population size. A quick quiz competition is used to engage the students whilst introducing the names of the three main types of selection before a class discussion point encourages the students to recognise which specific type of selection is represented by the rabbits. Key terminology including intermediate and extreme phenotypes and selection pressure are used to emphasise their importance during explanations. A change in the environment of the habitat and a change in the numbers of the rabbits introduces directional selection before students will be given time to discuss and to predict the shape of the sketch graph for disruptive selection. Students are challenged to apply their knowledge in the final task of the lesson by choosing the correct type of selection when presented with details of a population and answer related questions.

This lesson describes the sequence of events that occur during the phagocytosis of pathogens and the subsequent destruction by lysozymes. The engaging and detailed PowerPoint and accompanying resources have been primarily designed to cover the second part of point 2.4 of the AQA A-level Biology specification but includes an introduction to antigen-presentation so that the students are prepared for upcoming lessons on the cellular and humoral responses. At the start of the lesson, the students are challenged to recall that cytosis is a suffix associated with transport mechanisms and this introduces phagocytosis as a form of endocytosis which takes in pathogens and foreign particles. This emphasis on key terminology runs throughout the course of the lesson and students are encouraged to consider how the start or end of a word can be used to determine meaning. The process of phagocytosis is then split into 5 key steps and time is taken to discuss the role of opsonins as well as the fusion of lysosomes and the release of lysozymes. A series of application questions are used to challenge the students on their ability to make links to related topics including an understanding of how the hydrolysis of the peptidoglycan wall of a bacteria results in lysis. Students will be able to distinguish between neutrophils and monocytes from a diagram and at this point, the role of macrophages and dendritic cells as antigen-presenting cells is described so that it can be used in the next lesson. The lesson concludes with a brief introduction to lymphocytes so that initial links between phagocytosis and the specific immune responses are made.

This engaging lesson uses the example of resistant bacteria and the modern-day giraffe to describe how natural selection occurs. The PowerPoint and accompanying resources have been designed to cover point 17.2 (a) of the CIE A-level Biology specification but also explains that genetic diversity is important for selection and therefore covers 17.1 (d) at the same time. President Trump’s error ridden speech about viruses antibiotics is used at the beginning of the lesson to remind students antibiotics are actually a treatment for bacterial infections. Moving forwards, 2 quick quiz competitions will initially introduce MRSA and then will show the students that they can use this abbreviation to remind them to use mutation, reproduce, selection (and survive) and allele in their descriptions of evolution through natural selection. The main task of the lesson challenges the students to form a description that explains how this strain of bacteria developed resistance to methicillin. In doing so, they will see the principles of natural selection so they can be applied to different situations such as describing how the anatomy of the modern-day giraffe has evolved over time. The final part of the lesson introduces adaptations and convergent evolution and also links to the need for modern classification techniques which is covered later in topic 17.

This detailed lesson describes the relationship between the structure, properties and roles of water for living organisms. The engaging PowerPoint and accompanying resource have been designed to cover the details of specification point 2.1.2 (a) of the OCR A-level Biology A course and has been specifically designed to ensure that each role is illustrated using an example in prokaryotes or eukaryotes. As this is the first lesson in the biological molecules sub-module (2.1.2), which is a topic that students tend to find difficult or potentially less engaging, the planning has centred around the inclusion of a wide variety of tasks to cover the content whilst maintaining motivation and engagement. These tasks include current understanding and prior knowledge checks, discussion points and quick quiz competitions to introduce key terms and values in a memorable way. The start of the lesson considers the structure of water molecules, focusing on the covalent and hydrogen bonds, and the dipole nature of this molecule. Time is taken to emphasise the importance of these bonds and this property for the numerous roles of water and then over the remainder of the lesson, the following properties are described and discussed and linked to real-life examples: As a solvent to act as a transport medium in blood plasma Molecules are attracted by cohesive forces to enable transport in the xylem High latent heat of vaporisation for thermoregulation High specific heat capacity for the maintenance of a stable environment Peak density in the liquid form allowing ice to float The final part of the lesson introduces condensation and hydrolysis reactions and students will learn that a clear understanding of these reactions is fundamental as they will reappear throughout the module in the synthesis and breakdown of biological molecules.

This lesson describes the mechanisms of ventilation and gas exchange in insects. The PowerPoint and accompanying worksheets are the part of the second lesson in a series of 2 lessons which have been designed to cover the details that are set out in point 3.1.1 (f) of the OCR A-level Biology A specification. The first lesson in this series describes ventilation and gas exchange in bony fish In the previous lesson, the students were introduced to the different circulatory systems of mammals and bony fish and this knowledge is checked upon at the start of this lesson. This is relevant because the open circulatory system of an insect explains how oxygen is not transported in the blood but instead is absorbed from the body fluid that bathes the tissues. The next part of the lesson describes the structure of the spiracles, tracheae and tracheoles in the tracheal system and explains how this system is responsible for the delivery of oxygen to the open end of the tracheole for gas exchange with this fluid. As the tracheae are supported by chitin, which is similar in structure and function to cellulose and keratin respectively, a series of exam-style questions are used to challenge the students on their knowledge of those polymers from module 2.1.2 (biological molecules). As always, the mark scheme is embedded in the powerpoint so students can assess their understanding and progress. The final part of the lesson describes how squeezing of the tracheoles by the flight muscles and the changes in the volume of the thorax as a result of the movement of the wings are similar to mechanisms observed in mammals.

This fully-resourced lesson describes the roles of enzymes in catalysing both intracellular and extracellular reactions and the mechanism of enzyme action. The engaging PowerPoint and accompanying resources have been designed to cover points 2.1.4 (a, b & c) of the OCR A-level Biology A specification and includes descriptions of Fischer’s lock and key hypothesis and Koshland’s induced-fit model as well as a focus on catalase and the digestive enzymes as intracellular and extracellular enzymes respectively. The lesson has been specifically planned to tie in with module 2.1.2 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 final part of the lesson focuses on intracellular and extracellular enzymes. The students are challenged on their recall of the roles of DNA helicase and polymerase in DNA replication before they are challenged on their ability to apply their knowledge and understanding to an unfamiliar situation with questions about catalase and its role in the decomposition of hydrogen peroxide. The lesson concludes with one further set of exam-style questions that challenge their knowledge of carbohydrates, lipids and proteins from module 2.1.3 as they have to recognise some extracellular digestive enzymes from descriptions of their substrates.

This is a fully-resourced lesson that covers the content of specification point 5.1.5 (l) of the OCR A-level Biology A specification which states that students should be able to demonstrate and apply their knowledge and understanding of 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 lesson begins by using an idea from the quiz show POINTLESS to get them to recognise that myology is the study of muscles. This leads nicely into the next task, where they have to identify three further terms (from 12) which will also begin with myo and are the names of structures involved in the arrangement of skeletal muscle. Key terminology is used throughout the lesson so that students feel comfortable when they encounter this in questions. Students are introduced to the sarcomere and the bands and zones that are found within a myofibril so they can discover how most of these structures narrow but the A band, which is the length of the myosin filament, stays the same length between resting and contracted muscle. This has been designed to lead into a discussion point where they are encouraged to consider how the sarcomere can narrow but the lengths of the myofilaments can remain the same. The main task of the lesson involves the formation of a bullet point description of the sliding filament 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 OCR A-level Biology course and ties in nicely with the other lessons on this particular topic such as neuromuscular junctions as well as the other uploaded lessons from module 5

Students commonly confuse the two forms of cell division, so this revision lesson has been designed to address those mistakes and misconceptions. The PowerPoint and accompanying resources have been planned to challenge the students on their understanding of the details of points 1.2.1, 1.2.2 and 6.1.2 of the AQA GCSE biology and combined science specifications. The lesson goes through each of the three stages of the cell cycle including mitosis, to ensure that students can describe the key events and state the outcome in terms of the daughter cells. The lesson contains a series of tasks which include exam questions, discussions and a quiz which allow the students to assess their understanding. The final part of the lesson focuses on meiosis and specifically the differences to mitosis in terms of the number of cell divisions, the gametes formed, and their genetic make up. This lesson has been designed to be used for revision purposes in the lead up to the GCSE exams or in preparation for an end of topic test or mocks.

This fully-resourced revision lesson allows students to check on their understanding of Linnaeus’s and Woese’s classification systems. The engaging PowerPoint and accompanying resources have been designed to challenge the details of point B6.4 of the AQA GCSE biology and combined science specifications. The lesson contains a range of tasks including exam-questions and quizzes which provide opportunities for the students to assess their knowledge of kingdom, phylum, class, order, family, genus and species as the classification taxa and to recognise the binomial naming system. The lesson also reminds students that the three domain-system divides the Prokaryote kingdom into Archaea and Bacteria and describes how this system was developed once new evidence was discovered. As well as testing the content of B6.4, this lesson uses a series of questions to challenge understanding of linked topics which include eukaryotic and prokaryotic cell structures, microscopes, communicable diseases and ecological terms. This lesson has been planned for revision purposes in the lead up to the GCSE exams or before end of topic tests or mocks.

This engaging revision lesson challenges students on their understanding of the homeostatic control system that regulates blood glucose concentration. The PowerPoint and accompanying resources have been designed to check on the understanding of the details in specification point 5.3.2 of the AQA biology and combined science specifications. A common mistake in this topic is that students confuse glycogen with glucagon and use them incorrectly so time is spent to ensure that students recognise the difference between the complex carbohydrate and the hormone. In addition to challenging the students on their knowledge of this control system, the following linked topics are also challenged: key biological terms (beginning with G) the digestive system structures in a control system

This revision lesson challenges students to explain the results of an osmosis investigation and to calculate accelerations using 2 equations. The PowerPoint and accompanying resources have been designed to check on the understanding of these two topics as detailed in the AQA GCSE biology, physics and combined specifications. The lesson contains a range of tasks including worked examples, exam questions and quizzes which will remind students that water molecules move across partially permeable membranes by osmosis and how changes in the mass of a potato can be used to compare water concentrations in the potato and solution. Students will also recall that acceleration can be calculated from velocity-time graphs using change in velocity/time as well as through the use of F=ma.