This fully-resourced lesson describes how Mycobacterium tuberculosis and human immunodeficiency virus infect human cells and cause symptoms. The PowerPoint and accompanying resources have been designed to cover point 6.6 in unit 4 of the Edexcel International A-level Biology specification and ties in closely with the previous lesson where the structure of bacteria and viruses were compared. The lesson begins by ensuring that students recognise that TB is caused by the infection of a species of bacteria known as Mycobacterium tuberculosis and they will challenged to use their knowledge of scientific classification to recall that this pathogen is found in the mycobacteria genus. At this point, the students are told that the cell walls of this genus contain mycolic acids and later in the lesson they will have to work out that this specialist feature enables this pathogen to survive phagocytosis. A series of exam-style questions will challenge their knowledge of the respiratory and immune systems as they can understand how the bacterium travels to the alveoli where it is engulfed by a macrophage. Key terms like granuloma and necrosis are introduced and the sequence of events that occur following the formation of this aggregate of cells is described. The structure of viruses was covered during the previous lesson, so this next part of the lesson starts by challenging the students to recall the capsid, genetic material in the form of viral RNA and the lipid envelope. At this point, the students are introduced to gp120, the glycoprotein which is exposed on the surface of the lipid envelope, as this structure is critical for the entry of the virus into host cells. Students will annotate a basic diagram of HIV with these four structures which also has gp41 labelled. A quick quiz competition introduces the names of the enzymes found inside the capsid Moving forwards, the main task of this part of the lesson describes how HIV binds to the helper T cells, injects its capsid and integrates its DNA into the host’s genome in order to replicate to form virus particles (virions). Students are guided through the formation of a detailed answer about the mechanism of HIV and have to input key terms and structures where information is missing. Students will learn that the increase in the number of virus particles and a decrease in helper T cells and other immune cells results in infections like TB and by opportunistic pathogens and that this stage is recognised as AIDS

This fully-resourced lesson describes the role of memory cells in the secondary immune response. The PowerPoint and accompanying resources have been designed to cover specification point 6.7 (iv) of the Edexcel A-level Biology B specification but also contains a detailed description of the structure and function of antibodies and therefore covers this part of 6.7 (ii) As memory B cells differentiate into plasma cells that produce antibodies when a specific antigen is re-encountered, it was decided to link the immune responses and antibodies together in one lesson. The lesson begins by checking on the students incoming knowledge to ensure that they recognise that B cells differentiate into plasma cells and memory cells. This was introduced in a previous lesson on the specific immune response and students must be confident in their understanding if the development of immunity is to be understood. A couple of quick quiz competitions are then used to introduce key terms so that the structure of antibodies in terms of polypeptide chains, variable and constant regions and hinge regions are met. Time is taken to focus on the variable region and to explain how the specificity of this for a particular antigen allows neutralisation and agglutination to take place. The remainder of the lesson focuses on the differences between the primary and secondary immune responses and a series of exam-style questions will enable students to understand that the quicker production of a greater concentration of these antibodies in the secondary response is due to the retention of memory cells.

This fully-resourced lesson describes how rod cells in the mammalian retina detect stimuli to allow vision in low light intensity. The detailed PowerPoint and accompanying resources have been designed to cover the second part of point 8.5 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification and includes reference to the roles of rhodopsin, opsin, retinal, sodium ions, cation channels and hyperpolarisation in the formation of action potentials in the optic neurones. 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 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.

This fully-resourced revision lesson uses a range of activities to challenge the students on their knowledge of proteins from module 2.1.2. The engaging PowerPoint and accompanying resources have been designed to test the intricate details of specification points 2.1.2 (k), (l), (m), (n), (o) & (q) The range of activities include exam-style questions with displayed mark schemes, understanding checks and quick quiz competitions that will engage and motivate the students whilst they assess their understanding of this topic. The following concepts are tested during this lesson: The general structure of an amino acid The formation of dipeptides and polypeptides through condensation reactions The primary, secondary, tertiary and quaternary structure of a protein Biological examples of proteins and their specific actions (e.g. antibodies, enzymes, peptide hormones) The biuret test for proteins Time has been taken in the planning to make links to topics in upcoming modules such as the genetic code (2.1.3) and intracellular enzymes (2.1.4)

This lesson describes the evidence that led to the three-domain model of classification as an alternative to the five-kingdom model. The detailed PowerPoint and accompanying resources have been designed to cover point 3.1 (vii) of the Edexcel A-level Biology B specification and focuses on Carl Woese’s detailed study of the ribosomal RNA gene and the need for this evidence to be validated by the scientific community 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 lesson at the start of this topic, 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 and will understand that it wasn’t until 13 years after the discovery that it was adopted. Moving forwards, the rest of the lesson describes how molecular phylogeny uses other molecules that can be 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 1) and have to explain how mutations to DNA can also be used for comparative purposes.

This lesson describes the levels of organisation, including the aggregation of cells into tissues, tissues into organs and organs into organ systems. The detailed and engaging PowerPoint and accompanying resources have been designed to cover point (d) of AS unit 1, topic 2 of the WJEC A-level Biology specification and focuses on the levels of organisation in humans and plants. Please note that the lesson does not contain prepared slides of tissue as this is covered in a later lesson. The lesson begins by using the process of haematopoiesis from haematopoietic stem cells to demonstrate how the red blood cell and neutrophil differ significantly in structure despite arising from the same cell along the same cell lineage. A series of exam-style questions will not only challenge their knowledge of structure but also their ability to apply this knowledge to unfamiliar situations. These differences in cell structure is further exemplified by the epithelial cells of the respiratory tract and students are challenged to remember how the shape and arrangement of these cells differ in the trachea and alveoli in relation to their function. The link between specialised cells and tissues is made at this point of the lesson so students are reminded that a tissue is a group of cells that work together to perform a specific function or set of functions. Moving forwards, a quick quiz competition will challenge the students to recognise the liver, kidney, spinal cord and pancreas from a brief functional description and this leads into a series of questions that links back to topics 1 and earlier in topic 2 where proteins, organelles and carbohydrates were originally covered. These prior knowledge checks are found throughout the lesson, along with current understanding checks, and all of the mark schemes are embedded into the PowerPoint to allow students to assess their progress. In terms of organ systems, a quick task challenges them to recognise 8 of the 11 that are found in humans from descriptions and this leaves them to identify the gaseous exchange, digestive and reproductive systems as the remaining 3. The remainder of the lesson focuses on specialised plant cells and the differing shapes and features of the palisade and spongy cells in the mesophyll layer and the guard cells are covered at length and in detail. The cells found in the xylem and phloem tissue are also discussed.

This lesson describes how to analyse data using the Spearman rank correlation coefficient. The PowerPoint and accompanying exam-style question are part of the second lesson in a series of 2 lessons which have been designed to cover point 10.1 (vi) of the Edexcel A-level Biology B specification. The first lesson in this series described how to analyse data using the standard deviation and the t-test As with the previous lesson, a step by step guide is used to walk the students through the use of the formula to generate the rank coefficient and to determine whether there is a positive correlation, no correlation or a negative correlation. The students are also reminded of the null hypothesis and will be shown how to accept or reject this hypothesis and to determine significance. The students will work through an example with the class and then are given the opportunity to apply their newly-acquired knowledge to an exam-style question. The mark scheme is displayed on the PowerPoint so they can assess their understanding

This lesson describes the roles of the SAN and Purkyne fibres in the coordination of the three stages of the cardiac cycle. The PowerPoint and accompanying resources are part of the first lesson in a series of 2 lessons that have been designed to cover point [c] in topic 3 of AS unit 2 of the WJEC A-level Biology specification and has a specific focus on the pressure changes that occur in each stage of 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 next part 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. This rest of the lesson focuses on the roles of the SAN and Purkyne fibres as well as the AVN and the bundle of His in the coordination of the heartbeat, continually linking back to the work on the cycle. The SAN is introduced as the natural pacemaker and then time is given to study each step of the conduction of the impulse as it spreads away from the myogenic tissue in a wave of excitation. Moving forwards, students are encouraged to consider why a delay would occur at the AVN and then they will learn that the impulse is conducted along the Bundle of His to the apex so that the contraction of the ventricles can happen from the bottom upwards. The structure of the cardiac muscle cells is discussed and the final task of the lesson challenges the students to describe the conducting tissue, with an emphasis on the use of key terminology.

This lesson describes the reactants and products of the Haber Process and then explores and explains why the specific conditions are chosen for this reaction. The PowerPoint and accompanying worksheets have been designed to cover specification point 10.4.1 of the AQA GCSE Chemistry specification. The summary passage which is completed at the end of the lesson has been differentiated two ways. The lesson begins by challenging the students to use a description of the reaction to complete the balanced symbol equation. A quiz competition involving both Chemistry and Maths skills is used to reveal the temperature and pressure which are chosen for this reaction. Students will learn that this only produces a yield of 30% and therefore are encouraged to question why these conditions are chosen. In doing so, they are made to wear two “hats”, so that they consider it from both a Science angle but also a business angle. Their knowledge of reversible reactions and the effect of changing either the temperature or the pressure on the position of the equilibrium are constantly challenged and then checked through a range of progress check questions. As a result of this lesson, students will understand that these conditions are a compromise and be able to explain why.

This lesson describes the structure of DNA as a double-stranded polymer coiled into a double helix and focuses on nucleotides as the monomers. The PowerPoint and accompanying resources have been designed to cover the detail of point 3.4 of the Edexcel GCSE Biology & Combined Science specifications. The lesson begins with a reveal of the acronym DNA and students will learn that this stands for deoxyribonucleic acid. There is a focus on the use and understanding of key terminology throughout the lesson so time is taken to look at the meanings of the prefixes poly and mono as well as the suffix -mer. This leads into the description of DNA as a polymer which is made up of many monomers known as nucleotides. Students will be introduced to the three components of a DNA nucleotide and will learn that four different bases can be attached to the sugar. An observational task is used to get them to recognise that DNA consists of two strands and that complementary bases are joined by hydrogen bonds. Understanding checks are interspersed throughout the lesson along with mark schemes so that students can assess their progress

This fully-resourced lesson has been designed to cover the content found in specification point 2.5 (f) of the WJEC GCSE Biology specification which states that students should understand why animals need to regulate the conditions inside their bodies. This resource contains an engaging and detailed PowerPoint (45 slides) and accompanying worksheets The lesson begins by challenging the student’s literacy skills as they are asked to recognise the key term, optimum, from 6 of its’ synonyms. Moving forwards, a range of quiz competitions are used to introduce the term homeostasis and to provide a definition for this key process. Students are given a newspaper article about water and blood glucose so they can recognise 2 conditions which are controlled in the human body. The next part of the lesson looks at the importance of maintaining the levels of water and glucose by considering the medical problems that could arise if they move away from the optimum levels. Students will learn that body temperature is also controlled and links are made to earlier knowledge as they have to explain why an increase in temperature above the set point would be an issue because of the denaturation of enzymes. The rest of the lesson looks at the three parts that are included in all control systems before a final quiz round introduces the receptors, coordination centre and effectors in the control of body temperature. As stated at the top, this lesson has been designed for GCSE-aged students who are studying the WJEC GCSE Biology course, but it can be used with A-level students who need to go back over the key points before looking at the process in more detail

This engaging and detailed resource, which contains a PowerPoint and accompanying worksheets, has been designed to cover the content of point 2.5 (e) of the WJEC GCSE Biology specification that states that students should know the structure and functions of the following 9 parts of the eye: sclera cornea pupil iris lens choroid retina blind spot optic nerve The lesson was designed to include a wide range of activities to engage and motivate the students so that the knowledge is more likely to stick. These activities include Have you got an EYE for the IMPOSSIBLE, as shown in the cover image, where students have to pick out the 8 structures of the human eye from the list and avoid the IMPOSSIBLE answer. There is also a particular focus on the light-sensitive cells in the retina, the pupil reflex and the change in the shape of the lens to accommodate near and distant objects. This lesson has been designed for students studying the WJEC GCSE Biology course but is suitable for both older and younger students who may be studying the eye.

This is a fully-resourced lesson consisting of an engaging PowerPoint and differentiated worksheets which have been designed to cover the content of point 2.5 (i) as detailed on the WJEC GCSE Biology specification. This point states that students should demonstrate and apply their knowledge and understanding of how type I and II diabetes are caused and their respective treatments. There are links made throughout the lesson between this topic and the control of blood glucose concentration from specification point 2.5 (h). The lesson has been designed to take the format of a diabetic clinic where the students perform the duties of the attending doctor. They will move through the different stages of the role which includes identifying symptoms, diagnosis of type I or II and communication with the patients to reveal the findings. The wide range of activities will enable the students to learn how to spot that someone is suffering from diabetes and the similarities and differences between the different types so they can determine which one is being presented. The summary tasks challenge the students to construct a letter to a patient who is suffering from type II and to identify the correct type from another doctor’s letter. Understanding and previous knowledge checks are interspersed with quiz competitions, like the one shown in the cover image, which make the learning fun and memorable and enable the students to assess their progress. This lesson has been designed for students studying the WJEC GCSE Biology course but is suitable for both younger and older students who are focusing on this disease

This fully-resourced lesson describes the conversion of glucose to pyruvate during glycolysis in the cytoplasm and produces ATP and reduced NAD. The engaging PowerPoint and accompanying differentiated resources have been designed to cover point 5.1 (i) as detailed in the Edexcel A-level Biology B specification and includes the phosphorylation of glucose, the breakdown to glycerate-3-phosphate and the subsequent oxidation to produce ATP and the reduced coenzyme. The lesson begins with the introduction of the name of the stage and then explains how the phosphorylation of the monosaccharides, the breakdown into GP and the production of the ATP, reduced coenzymes and pyruvate are the stages that need to be known for this specification. Time is taken to go through each of these stages and key points such as the use of ATP in phosphorylation are explained so that students can understand how this affects the net yield. A quick quiz competition is used to introduce NAD and the students will learn that the reduction of this coenzyme, which is followed by the transport of the protons and electrons to the cristae for the electron transport chain is critical for the overall production of ATP. Understanding checks, in a range of forms, are included throughout the lesson so that students can assess their progress and any misconceptions are immediately addressed.

This fully-resourced lesson describes how reproductive isolation can lead to allopatric and sympatric speciation. The engaging PowerPoint and accompanying resources have been designed to cover point 3.2 (iii) of the Edexcel A-level Biology B specification. The lesson begins by using the example of a hinny, which is the hybrid offspring of a horse and a donkey, to challenge students to recall the biological classification of a species. Moving forwards, students are introduced to the idea of speciation and the key components of this process, such as isolation and selection pressures, are covered and discussed in detail. Understanding and prior knowledge checks are included throughout the lesson to allow the students to not only assess their progress against the current topic but also to make links to earlier topics in the specification. Time is taken to look at the details of allopatric speciation and how the different mutations that arise in the isolated populations and genetic drift will lead to genetic changes. The example of allopatric speciation in wrasse fish because of the isthmus of Panama is used to allow the students to visualise this process. The final part of the lesson considers sympatric speciation and again a wide variety of tasks are used to enable a deep understanding to be developed.

This fully-resourced lesson explains why the speed of transmission along myelinated axons is greater than along non-myelinated axons. The PowerPoint and accompanying resources have been designed to cover point 9.5 (iii) of the Edexcel A-level Biology B specification which states that students should understand the role of saltatory conduction in the transmission of action potentials. A wide range of activities have been written into this resource to maintain the motivation of the students whilst ensuring that the detail is covered in real depth. Interspersed with the activities are understanding checks and prior knowledge checks to allow the students to not only assess their understanding of the current topic but also challenge themselves to make links to earlier topics such as the movement of ions across membranes and biological molecules. Time at the end of the lesson is also given to future knowledge such as the involvement of autonomic motor neurones in the stimulation of involuntary muscles. Over the course of the lesson, students will learn and discover the myelin sheath wrapped around the axons of sensory and motor neurones allows these neurones to conduct impulses quickly between receptors and the CNS and between the CNS and effectors. There is a focus on this myelin sheath and specifically how the insulation is not complete all the way along which leaves gaps known as the nodes of Ranvier which allow the entry and exit of ions. Saltatory conduction is poorly understood (and explained) by a lot of students so time is taken to look at the way that the action potential jumps between the nodes and this is explained further by reference to local currents. The rest of the lesson focuses on the other two factors which are axon diameter and temperature and students are challenged to discover these two by focusing on the vampire squid.

This detailed lesson describes the formation and effects of excitatory and inhibitory postsynaptic potentials . The PowerPoint has been designed to cover point 9.5 (v) of the Edexcel A-level Biology B specification. This is a topic which is generally poorly understood by students or brushed over so considerable time has been taken to design the activities to motivate the students so that the content is memorable whilst still being covered in detail. Links are continually made to earlier topics in this topic such as synapses and generator potentials but also to topics covered in the previous year. The lesson begins by challenging the students to recognise a description of generator potential and they will then discover that this is also known as an EPSP. Students will recall that a small depolarisation may not lead to the opening of the voltage gated channels and therefore the full depolarisation which is needed for the initiation of an action potential and will discuss how this problem could be overcome. Lots of discussion points like this are included in the lesson to encourage the students to challenge and debate why a particular process of mechanism occurs. Students will therefore learn that EPSPs can be combined and this is known as summation. A quiz round is used to introduce temporal and spatial summation. Moving forwards, students are presented with a number of examples where they have to decide why type of summation is involved. Again, the lesson has been written to include real-life examples such as chronic pain conditions so the chances of the content sticking is increased. The final part of the lesson introduces IPSPs and the effect of these on summation and action potentials is discussed.

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 the transport mechanism of osmosis as the movement of water molecules from a high water potential to a lower water potential. The PowerPoint and accompanying resources are part of the second lesson in a series of 4 lessons which have been designed to cover point [c] as detailed in AS unit 1, topic 3 of the WJEC A-level Biology specification and also describes how cells are affected by this movement of water It’s likely that students will have used the term concentration in their osmosis definitions at GCSE, so the aim of the starter task is to introduce water potential to allow students to begin to recognise osmosis as the movement of water molecules from a high water potential to a lower potential, with the water potential gradient. Time is taken to describe the finer details of water potential to enable students to understand that 0 is the highest value (pure water) and that this becomes negative once solutes are dissolved. Exam-style questions are used throughout the lesson to check on current understanding as well as prior knowledge checks which make links to previously covered topics such as the lipid bilayer of the cell membrane. The remainder of the lesson focuses on the movement of water when animal and plant cells are suspended in hypotonic, hypertonic or isotonic solutions and the final appearance of these cells is described, including any issues this may cause.