This lesson describes how the structures of the xylem vessels, sieve tube elements and companion cells relates to their functions. Both the engaging and detailed PowerPoint and accompanying resources have been designed to cover point 3.1.3 (b) [i] of the OCR A-level Biology A specification. The lessons begins by challenging the students to identify the substances that a plant needs for the cellular reactions, where they are absorbed and where these reactions occur in a plant. The aim of this task is to get the students to recognise that water and mineral ions are absorbed in the roots and needed in the leaves whilst the products of photosynthesis are in the leaves and need to be used all over the plant. Students will be reminded that the xylem and phloem are part of the vascular system responsible for transporting these substances and then the rest of the lesson focuses on linking structure to function. A range of tasks which include discussion points, exam-style questions and quick quiz rounds are used to describe how lignification results in the xylem as a hollow tube of xylem cells to allow water to move as a complete column. They will also learn that the narrow diameter of this vessel allows capillary action to move water molecules up the sides of the vessel. The same process is used to enable students to understand how the structures of the companion cells allows assimilates to be loaded before being moved to the sieve tube elements through the plasmodesmata. It is estimated that it will take in excess of 2 hours of A-level teaching time to cover the detail which has been written into this lesson

This clear and concise lesson describes the meaning of a gene locus and explains how the inheritance of two or more genes that have loci on the same chromosome demonstrates linkage. The engaging PowerPoint and associated resource have been designed to cover points 3.9 (i) and (ii) of the Edexcel International A-level Biology specification and makes clear links to the upcoming topic of meiosis when describing the effect of crossing over on this linkage This is a topic which can cause confusion for students so time was taken in the design to split the concept into small chunks. There is a clear focus on how the number of original phenotypes and recombinants can be used to determine linkage and suggest how the loci of the two genes compare. Important links to other topics such as crossing over in meiosis are made to enable students to understand how the random formation of the chiasma determines whether new phenotypes will be seen in the offspring or not. Linkage is an important cause of variation and the difference between observed and expected results and this is emphasised on a number of occasions. The main task of the lesson acts as an understanding check where students are challenged to analyse a set of results involving the inheritance of the ABO blood group gene and the nail-patella syndrome gene to determine whether they have loci on the same chromosome and if so, how close their loci would appear to be.

This lesson describes how the action of the radial and circular muscles of the iris causes the pupil to dilate or contract. The PowerPoint has been designed to cover point 8.6 (ii) of the Edexcel International A-level Biology specification and includes key details such as the innervation of the smooth muscles by divisions of the autonomic nervous system. Students will learn how: the contraction of the radial muscles pulls the iris radially and enlarges the pupil, allowing more light to enter when an individual is in a room with dim light and that this contraction is the result of the conduction of an electrical impulse along a sympathetic motor neurone. the contraction of the circular muscles constricts the pupil to reduce the light that enters the eye, in order to prevent damage to the photosensitive cells in the retina. This is the result of innervation by an impulse conducted along a parasympathetic neurone

This lesson describes how the nervous system allows effectors to respond to stimuli and also describes hormonal control in animals. The PowerPoint and accompanying resources have been primarily designed to cover points 8.2 & 8.13 of the Edexcel International A-level Biology specification but it can also be used as a revision lesson as there are numerous prior knowledge checks of muscle contraction, protein structure and the control of gene expression. The lesson begins by challenging the students to recall that a control system contains sensory receptors, a coordination centre and effectors. Sensory receptors are covered in detail later in the topic when some key examples are considered as well as those in the retina, but time is taken now to describe how these structures act like transducers, converting one form of energy into electrical energy and the Pacinian corpuscle is used as an example. The students will learn that the communication between the receptors and the coordination centre and the effectors is by cell signalling and that the effectors can be muscles which contract or glands that release chemicals. The next part of the lesson looks at the differing responses from the nervous and hormonal systems and discusses how this can be governed by the need for a rapid response or more of a long term effect. In terms of nervous control, the students are challenged on their recall of the sliding filament theory of muscle contraction as covered in topic 7. Moving forwards, the students will learn that hormones can be either peptide or steroid hormones and their action at a target cell differs based on their form. Students are tested on their knowledge of protein structure by a series of exam-style questions on insulin and glucagon. They are reminded that steroid hormones can pass directly through the cell membrane and their knowledge of the control of gene expression by transcription factors is tested through a task involving oestrogen and the ER receptor. The lesson concludes by reminding students that the control of heart rate, as covered in topic 7, is a coordinated response that involves both nervous and hormonal control.

This fully-resourced lesson describes the roles of adrenaline in the fight or flight response. The engaging PowerPoint and accompanying resources have been designed to cover point 7.14 of the Edexcel International A-level Biology specification At the start of the lesson, the students have to use the knowledge acquired in the most recent lessons on the function of the heart to reveal the key term medulla and this leads into the description of the structure of the adrenal glands in terms of this inner region. The main part of the lesson focuses on the range of physiological responses of the organs to the release of adrenaline. Beginning with glycogenolysis, the need for adrenaline to bind to adrenergic receptors is described, including the activation of cyclic AMP. A quiz competition is used to introduce other responses including lipolysis, vasodilation, bronchodilation and an increase in stroke volume. Links to previous topics are made throughout the lesson and students are challenged on their knowledge of heart structure, triglycerides and polysaccharides.

This detailed lesson describes how water can be moved through plant cells by the apoplastic and symplastic pathways. The engaging PowerPoint and accompanying resource have been designed to cover point 4.7 (ii) of the Edexcel A-level Biology B specification and includes a description of the movement from the endodermis to the xylem to tie in with the following lesson on the cohesion-tension model. The lesson begins by looking at the specialised features of the root hair cell to allow students to understand how these epidermal cells absorb water and mineral ions from the soil. Moving forwards, students are introduced to key terminology such as epidermis and root cortex before time is taken to look at the different pathways that water and minerals use to transverse across the cortex. Discussion points are included throughout the lesson to encourage the students to think about each topic in depth and challenges them to think about important questions such as why the apoplastic pathway is needed for the water carrying the ions. Students will be introduced to the Casparian strip and will learn how this layer of cells blocks the apoplastic pathway. A step by step method using class questions and considered answers is used to guide them through the different steps and to support them when writing the detailed description.

This fully-resourced lesson guides students through the interpretation of genetic pedigree diagrams for the inheritance of a single gene. The clear PowerPoint and accompanying resources have been designed to cover point 2.13 (ii) of the Pearson Edexcel A-level Biology A specification and includes the inheritance of multiple allele characteristics as well as those that demonstrate codominance. In order to minimise the likelihood of errors and misconceptions, step by step guides have been included throughout the lesson to support the students with the following: Writing parent genotypes Working out the different gametes that are made following meiosis Interpreting Punnett crosses to work out phenotypic ratios Students can often find pedigree trees the most difficult to interpret and to explain so exemplar answers are used as well as differentiated worksheets provided to support those students who need extra assistance.

This lesson describes how the structure of the mammalian lung is adapted for rapid gaseous exchange. The engaging PowerPoint has been designed to cover point 2.1 (iii) of the Edexcel International A-level Biology specification and focuses on the essential features of the alveolar epithelium as well as the mechanism of ventilation to maintain a steep concentration gradient for the simple diffusion of oxygen and carbon dioxide. Gas exchange at the alveoli is a topic that was covered at GCSE and considered during the previous lessons in topic 2.1 so this lesson has been written to challenge the recall of that knowledge and to build on it. The main focus of the first half of the lesson is the type of epithelium found lining the alveoli and students will discover that a single layer of flattened cells known as simple, squamous epithelium acts to reduce the diffusion distance. The following features of the alveolar epithelium are also covered: Surface area Moist lining Production of surfactant The maintenance of a steep concentration gradient is the role of the respiratory system and the next part of the lesson focuses on the diaphragm and intercostal muscles. 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.

This lesson describes the origin of phagocytes and the sequence of events that occur during the phagocytosis of pathogens. The engaging and detailed PowerPoint and accompanying resources have been designed to cover point 11.1 (a) of the CIE International A-level Biology specification and also includes an introduction to antigen-presentation so that the students are prepared for the next lesson on the role of T and B lymphocytes 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 fully-resourced lesson describes the structure and properties of the two isomers of glucose and ribose as examples of monosaccharides. The detailed and engaging PowerPoint and accompanying resources have been designed to cover specification point 2.1.2 (d) of the OCR A-level Biology A course and also looks at galactose, fructose and deoxyribose. The lesson begins with a made-up round of the quiz show POINTLESS, where students have to try to identify four answers to do with carbohydrates. In doing so, they will learn or recall that these molecules are made from carbon, hydrogen and oxygen, that they are a source of energy which can sometimes be rightly or wrongly associated with obesity and that the names of the three main groups is derived from the Greek word sakkharon. Using the molecular formula of glucose as a guide, students will be given the general formula for the monosaccharides and will learn that deoxyribose is an exception to the rule that the number of carbon and oxygen atoms are equal. Moving forwards, students have to study the displayed formula of glucose for two minutes without being able to note anything down before they are challenged to recreate what they saw in a test of their observational skills. At this point of the lesson, the idea of numbering the carbons is introduced so that the different glycosidic bonds can be understood in an upcoming lesson as well as the recognition of the different isomers of glucose. The difference between alpha and beta-glucose is provided and students are again challenged to draw a molecule of glucose, this time for the beta form. The remainder of the lesson focuses on the roles of the 6 monosaccharides which includes a series of understanding and application questions where the students are challenged to describe the role of ribose in RNA and to suggest why ribose could be considered to be an important molecule for active transport and muscle contraction.

This fully-resourced lesson describes how magnification and resolution can be achieved using light and electron microscopy. The engaging PowerPoint and accompanying resources have been designed to cover the content of point 2.1 (vi) of the Edexcel A-level Biology B specification and the importance of specimen staining is also briefly introduced so that students are prepared for the next lesson. To promote engagement and focus throughout this lesson, the PowerPoint contains a quiz competition with 7 rounds. The quiz rounds found in this lesson will introduce the objective lens powers, the names of the parts of a light microscope and emphasise some of the other key terms such as resolution. The final round checks on their understanding of the different numbers that were mentioned in the lesson, namely the differing maximum magnifications and resolutions. Time is taken to explain the meaning of both of these microscopic terms so that students can recognise their importance when considering the organelles that were met earlier in topic 2. By the end of the lesson, the students will be able to explain how a light microscope uses light to form an image and will understand how electrons transmitted through a specimen or across the surface will form an image with a TEM or a SEM respectively.

This fully-resourced lesson describes the conversion of Calvin cycle intermediates to carbohydrates, lipids and amino acids. The engaging and detailed PowerPoint and accompanying resources have been primarily designed to cover point 13.1 (h) of the CIE A-level Biology specification concerning the uses of GP and TP but as the lesson makes continual references to biological molecules, it can act as a revision tool for a lot of the content of topic 2. The previous lesson described the three stages of the Calvin cycle and this lesson builds on that understanding to demonstrate how the intermediates of the cycle, GP and TP, are used. The start of the lesson challenges the students to identify two errors in a diagram of the cycle so that they can recall that most of the TP molecules are used in the regeneration of ribulose bisphosphate. A quiz version of Pointless runs throughout the lesson and this is used to challenge the students to recall a biological molecule from its description. Once each molecule has been revealed, time is taken to go through the details of the formation and synthesis of this molecule from TP or from GP in the case of fatty and amino acids. The following molecules are considered in detail during this lesson: glucose (and fructose and galactose) sucrose starch and cellulose glycerol and fatty acids amino acids nucleic acids A range of activities are used to challenge their prior knowledge of these molecules and mark schemes are always displayed for the exam-style questions to allow the students to assess their understanding. As detailed above, this lesson has been specifically written to tie in with the earlier lessons in this topic on the structure of the chloroplast, the light-dependent stage of photosynthesis and the Calvin cycle.

This lesson describes how the critical evaluation of new data by the scientific community leads to new taxonomic groupings, like the three domains of life. The detailed PowerPoint and accompanying resources have been designed to cover point 4.14 (ii) of the Edexcel International A-level Biology specification and focuses on the introduction of the three-domain system following Carl Woese’s detailed study of the ribosomal RNA gene. The lesson begins with an introduction of Woese and goes on to describe how he is most famous for his definition of the Archaea as a new domain of life. Students were introduced to domains and the other classification taxa in a previous lesson, so their recall of this knowledge is continually tested and built upon as details are added. Students will discover the key differences between Archaea and Bacteria that led to the splitting of the prokaryotae kingdom and the addition of this higher classification rank. Moving forwards, the rest of the lesson describes how molecular phylogeny uses other molecules and that these are compared between species for classification purposes. One of these is a protein called cytochrome which is involved in respiration and can be compared in terms of primary structure to determine relationships. At this point in the lesson, the students are also tested on their knowledge of the nature of the genetic code (as covered in topic 2) and have to explain how mutations to DNA can also be used for comparative purposes.

This lesson discusses the roles of non-governmental organisations such as WWF and CITES in local and global conservation. The PowerPoint and accompanying worksheets have been primarily designed to cover point 18.3 (g) of the CIE A-level Biology specification but as this is a lesson near to the end of topic 18, a number of tasks have been included to test the students on their understanding of 18.1, 18.2 and 18.3. Many hours of research have gone into the planning of this lesson to ensure that a range of interesting biological examples are included, with the aim of fully engaging the students in the material to increase its relevance. The students will learn that the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) was first agreed in 1973 and that 35000 species are currently found in appendix I, II or III. Time is taken to go through the meaning of each appendix and then the following animal and plant species are used to explain the finer details of the agreement and to demonstrate how the conservation of these species has been affected: Tree pangolin, eastern black rhino for CITES appendix I Darwin’s orchid for CITES appendix II Four-horned antelope for CITES appendix III Exam-style questions are used to check on their understanding of the current topic as well as to challenge their knowledge of previously-covered topics such as the functions of keratin, when considering the structure of the rhino horn. Each of these questions has its own markscheme which is embedded in the PowerPoint and this allows the students to constantly assess their progress. The second half of the lesson focuses on the World Wide Fund for Nature (WWF) and again some examples of conservation projects which have been funded by this international organisation are considered. The implementation of wildlife corridors in east Africa to promote migration and interbreeding is discussed and the measures in place to protect the Dinaric region are also described. As detailed at the top, this lesson can be used for revision of some of the content of topic 18 whilst teaching the content of specification point 18.3 (g)

This fully-resourced lesson guides students through the principles of monohybrid inheritance, focusing on the importance of alleles. The PowerPoint and accompanying resources have been designed to cover points (a & b) in topic 3 of A2 unit 4 of the WJEC A-level Biology specification and includes the inheritance of alleles that demonstrate codominance. In order to minimise the likelihood of errors and misconceptions, step by step guides have been included throughout the lesson to support the students with the following: Writing parent genotypes Working out the different gametes that are made following meiosis Interpreting Punnett crosses to work out phenotypic ratios Students can often find pedigree trees the most difficult to interpret and to explain so exemplar answers are used as well as differentiated worksheets provided to support those students who need extra assistance

This lesson describes the importance of homeostasis using negative feedback control and also describes the meaning of positive feedback. The PowerPoint and accompanying resources have been designed to the content with point 9.1 of the Edexcel A-level Biology B specification and explains how this feedback control maintains systems within narrow limits but has also been planned to provide important details for upcoming topics such as osmoregulation, thermoregulation and the depolarisation of a neurone. The normal ranges for blood glucose concentration, blood pH and body temperature are introduced at the start of the lesson to allow students to recognise that these aspects have to be maintained within narrow limits. A series of exam-style questions then challenge their recall of knowledge from topics 1-8 to explain why it’s important that each of these aspects is maintained within these limits. The students were introduced to homeostasis at GCSE, so this process is revisited and discussed, to ensure that students are able to recall that this is the maintenance of a state of dynamic equilibrium. A quick quiz competition is used to reveal negative feedback as a key term and students will learn how this form of control reverses the original change and biological examples are used to emphasise the importance of this system for restoring levels to the limits (and the optimum). The remainder of the lesson explains how positive feedback differs from negative feedback as it increases the original change and the role of oxytocin in birth and the movement of sodium ions into a neurone are used to exemplify the action of this control system.

This is a fully-resourced lesson which uses exam-style questions, engaging quiz competitions, quick tasks and discussion points to challenge students on their understanding of the content of topics B1 - B3, that will assessed on PAPER 1. It has been specifically designed for students on the OCR Gateway A GCSE Combined Science course who will be taking the FOUNDATION TIER examinations but is also suitable for students taking the higher tier who need to ensure that the key points of each of the sub-topics are embedded. The lesson has been written to take place in numerous shops that could be found on the high street to allow the following sub-topics to be covered: Eukaryotes and prokaryotes The prefixes of size and converting between units The cell structures of animal and plant cells The principles of organisation The structure of the heart and the circulatory system The features of the alveoli which enable efficient gas exchange Temperature and photosynthesis The role of enzymes in reactions The functions of the components of blood The homeostatic control of blood glucose by insulin secretion Diabetes type I and II The hormones involved in the menstrual cycle Mitosis and the cell cycle The structures involved in a nervous reaction Reflex arcs In order to maintain challenge whilst ensuring that all abilities can access the questions, the majority of the tasks have been differentiated and students can ask for extra support when they are unable to begin a question. Due to the extensiveness of this revision lesson, it is estimated that it will take in excess of 3 teaching hours to complete the tasks and therefore this can be used at different points throughout the duration of the course as well as acting as a final revision before the PAPER 1 exam

This fully-resourced lesson describes the reactions of the light independent stage of photosynthesis that takes place in the chloroplast stroma. The detailed PowerPoint and accompanying resources have been designed to cover points 5.7 (iv, v & vi) of the Edexcel A-level Biology B specification and lengthy planning has ensured that links are continually made to the previous lesson on the light-dependent stage 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 GALP 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 GALP The use of the majority of the GALP 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 GALP 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 lessons on the synthesis of organic molecules from GALP and limiting factors

This detailed lesson describes how the structure of collagen and haemoglobin are related to their function. The engaging PowerPoint and accompanying worksheet have been designed to cover specification point 1.3 (v) of the Edexcel A-level Biology B course and also introduces fibrous and globular proteins as a result. The first part of the lesson looks at the structure of haemoglobin, and describes how the presence of an iron-containing haem group on the outside of the 4 polypeptide chains explains its ability to form oxyhaemoglobin. Moving forwards, the importance of the solubility of this protein is considered and related to the direction that the hydrophobic R groups point. At this point of the lesson, the students are challenged to construct a comparison table which can be filled in as the lesson progresses and as they are given more details of collagen. The section of the lesson concerning collagen begins with the introduction of its function in the artery wall so that students can recognise how fibrous proteins have roles associated with mechanical strength. Time is taken to discuss their solubility as well as the presence of repetitive amino acid sequences. The remainder of the lesson considers four more proteins and the final task challenges the students to use their completed table to write a summary passage comparing globular and fibrous proteins.

The engaging Powerpoint and accompanying worksheet which come as part of this lesson resource have been designed to cover specification point 2.5 (k) as detailed in the WJEC GCSE Biology specification which states that students should understand the roles of the effectors in temperature regulation. A wide range of activities which include Biology and Maths tasks and quiz competitions are interspersed with understanding and prior knowledge checks so that students are engaged and motivated whilst learning the key content in a memorable way and checking their progress. Students will learn that the body temperature is maintained at 37 degrees celsius by a homeostatic control system called thermoregulation and will be challenged to recall the topic of enzymes to explain why this is so important. Time is taken to look at the responses brought about the effectors such as vasodilation and shivering and links are made to the structures of the skin such as the involvement of the erector muscles. Students will recognise how these mechanisms lead a decrease or increase in body temperature back to the set point. Links are also made between the Sciences so that there is a deeper understanding of exactly why sweating cools the body down. This lesson has been designed for students studying the WJEC GCSE Biology course but is suitable for older students who are studying Biology at A-level and need to recall the key details of thermoregulation.