This revision resource includes exam questions, understanding checks and quiz competitions, all of which have been designed with the aim of motivating and engaging the students whilst they assess their understanding of the content found in topic 2 (Organisation of the organism) of the CIE IGCSE Biology specification for examination in June and November 2020 and 2021. This revision resource contains an engaging PowerPoint (53 slides) and an associated worksheet. The range of activities have been designed to cover as much of the Core and Supplement content as possible but the following sub-topics have been given particular attention: The function of the organelles found in animal and plant cells The features of specialised cells which allow them to perform their function The mitochondria and the production of energy for use in cell activities Calculating size and magnification by converting between millimetres and micrometres Tissues, organs and organ systems

This lesson has been designed to cover the content of specification point 4.1.2.1 (Chromosomes) and 4.1.2.2 (Mitosis and the cell cycle) of the AQA GCSE Biology and Combined Science course. Cell division is a topic which can cause students a number of problems so this lesson has been designed to ensure that the key details are covered and checked constantly. As well as the understanding and previous knowledge checks, quiz competitions are written into the lesson to maintain engagement and motivation. The lesson begins with the introduction of the term cell cycle and students will learn that the cycle consists of three stages. The key details of each of these stages is covered during the main part of the lesson so that students can meet the specification requirements of being able to describe the main events. Time is allotted for discussion to encourage students to converse about important points such as what happens to the replicated chromosomes during mitosis to enable identical daughter cells to be produced. Opportunities are taken to make links to other topics such as animal and plant cells as students are challenged to recall the functions of some sub-cellular structures. The final part of the lesson involves a series of summary questions which challenges the students to not only recall content but also to apply to unfamiliar organisms and it is not until the final question that they will answer a question about the cell cycle in humans.

This engaging lesson covers the detail of the 2nd part of specification point 5.1.3 (d) of the OCR A-level Biology specification which states that students should demonstrate and apply an understanding of the importance of synapses in summation and control, including inhibitory and excitatory synapses. 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 module such as synapses and generator potentials but also to topics covered in the previous year and still to be covered. 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 has been designed for students studying on the OCR A-level Biology course and ties in well with the other uploaded lessons from module 5.1.3 on sensory receptors, neurones, nerve impulses and cholinergic synapses

This is a fully-resourced lesson which covers the detail of specification point 15.1 (b) of the CIE International A-level Biology specification which states that students should be able to describe the structure of a sensory and a motor neurone. 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 also distinguish between them based on their structural features. Time is taken to look at the importance of the myelin sheath that is present in both neurones. Students will be introduced to the need for the entry of ions to cause depolarisation and will learn that this is only possible at the nodes of Ranvier when there is a myelin sheath. Key terminology such as saltatory conduction is introduced and explained and the lesson concludes with the introduction of the different types of motor neurones based on the type of muscle which they innervate. This lesson has been designed for students studying on the CIE International A-level Biology course and ties in well with the other uploaded lessons which cover the content of topic 15.1 (Control and coordination in mammals) .

This concise and engaging lesson has been designed to cover specification point 15.1 (j) of the CIE International A-level Biology specification which states that students should be able to describe the ultrastructure of striated muscle with particular reference to sarcomere structure. The wide range of key terms and regions are introduced in a fun and memorable way using a variety of activities that include quiz competitions and then understanding checks are used throughout to assess their progress and ensure that any misconceptions are addressed. Connections are made to the upcoming topic of the sliding filament model as the students discover that despite the shortening of the sarcomere (and I band and H zone) during contraction, the fact that the A band remains the same length shows how the filaments slide over each other. The two main tasks of the lesson challenge the students to label a diagram of a sarcomere and then the microscope image as shown in the cover picture. This lesson has been designed to tie in well with the other uploaded lessons that cover the content of topic 15.1 of the CIE International A-level Biology course which is the control and coordination in mammals

This lesson has been written to cover the detail of specification point 15.1 (f) of the CIE International A-level Biology specification which states that students should be able to explain the importance of myelination. 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 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 consider the structure of the 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 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 lesson has been designed for students studying the CIE International A-level Biology course and the other part of this specification point which covers the refractory period was explained in the previous lesson on the transmission of the action potential

This concise, fully-resourced lesson covers the content of specification point 15.1 (i) of the CIE International A-level Biology specification which states that students should be able to describe the roles of the neuromuscular junction, transverse tubules and sarcoplasmic reticulum in the stimulation of the contraction of striated muscle. Due to a number of similarities between these structures and cholinergic synapses, this lesson uses prior knowledge of these connections between neurones to build a good understanding of the junctions. Students will discover that the events that occur at an axon tip mirror those which happen at the pre-synaptic bulb and this is then developed to look at the differences in terms of the events once the acetylcholine has bound to its receptor sites. There is a focus on the structure of the sarcolemma and time is taken to explain how the action potential is passed from this membrane to the transverse tubules in order to stimulate the release of calcium ions from the sarcoplasmic reticulum. As a result, this lesson ties in nicely with the following lesson on the contraction of skeletal muscle and students will be able to link the binding to troponin in that lesson to the release of these ions from this lesson. Both of the main tasks of the lesson have been differentiated so that students of all abilities can access the work and make progress. This lesson has been designed for those students studying on the CIE International A-level Biology course and ties in well with the other uploaded lessons on topic 15.1 (Control and coordination in mammals)

This concise lesson has been written to cover the detail of specification point 14.1 (d) of the CIE International A-level Biology specification which states that students should be able to describe the deamination of amino acids and outline the formation of urea in the urea cycle. Over the course of the lesson, students will discover that the amino group is removed during deamination to produce a keto acid and ammonia. They are encouraged to consider why the ammonia cannot accumulate in the body before looking at the different stages of the urea cycle. Instead of simply giving them the diagram of the urea cycle, students are given the opportunity to study the cycle when it is split into one of the three stages but are not allowed to draw. This task will challenge the students on their observational skills and then their ability to apply when they are given a question on the cycle. Included throughout the lesson are a selection of understanding checks and prior knowledge checks which allows the students to assess their progress against the current topic as well as challenging them to make links to previously covered topics. This lesson has been designed for students on the CIE International A-level Biology course and ties in well with the other uploaded lessons on topic 14.1 (Homeostasis in mammals)

This lesson focuses on the use and explanation of key genetic terms which will support students in their understanding of the topic 16 (inherited change) of the CIE International A-level Biology specification. In this topic, students are expected to use genetic diagrams to solve problems and this is only possible with a clear understanding of the genetic terminology that will be used in related exam questions. As some of these terms were met at GCSE, this fully-resourced lesson has been designed to include a wide range of activities that build on this prior knowledge and provide clear explanations as to their meanings as well as numerous examples of their use in both questions and exemplary answers. The main task provides the students with an opportunity to apply their understanding by recognising a dominance hierarchy in a multiple alleles characteristic and then calculating a phenotypic ratio when given a completed genetic diagram. Other tasks include prior knowledge checks, discussion points to encourage students to consider the implementation of the genetic terms and quiz competitions to introduce new terms, maintain engagement and act as an understanding check. The 16 terms are genome, gene, chromosome, gene locus, homologous chromosomes, alleles, dominant, recessive, genotype, codominance, multiple alleles, autosomes, sex chromosomes, phenotype, homozygous and heterozygous

This engaging lesson looks at the myogenic nature of cardiac muscle and explores the roles of the SAN, AVN, Bundle of His and Purkyne fibres in the normal electrical activity of the heart. The PowerPoint and accompanying resources have been designed to cover the points 7.8 (i & ii) of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification. The lesson begins with the introduction of the SAN 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. The lesson has been written to make clear links to the cardiac cycle and the structure of the heart and students are challenged on their knowledge of this system from topic 1. 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 Due to the detailed nature of this lesson, it is estimated that it will take about 2 hours of A-level teaching time to cover the two specification points

This fully-resourced lesson looks at the roles of glycolysis in aerobic and anaerobic respiration and explains how the sequence of reactions results in glucose being converted to pyruvate. The engaging PowerPoint and accompanying differentiated resources have been designed to cover point 7.4 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification. The lesson begins with the introduction of the name of the stage and then explains how the phosphorylation of the hexoses and the production of the ATP, 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 lesson has been written to tie in with the other uploaded lessons on the Link reaction, Krebs cycle, oxidative phosphorylation and the production of lactate.

This clear and concise lesson looks at the role of the Link reaction in the conversion of pyruvate to acetyl coenzyme A which will then enter the Krebs cycle. The PowerPoint has been designed to cover the fourth part of point 5.2 of the AQA A-level Biology specification which states that students should know about this conversion and the production of reduced NAD The lesson begins with a challenge, where the students have to recall the details of glycolysis in order to form the word matrix. This introduces the key point that this stage occurs in this part of the mitochondria and time is taken to explain why the reactions occur in the matrix as opposed to the cytoplasm like glycolysis. Moving forwards, the Link reaction is covered in 5 detailed bullet points and students have to add the key information to these points using their prior knowledge as well as knowledge provided in terms of NAD. The students will recognise that this reaction occurs twice per molecule of glucose and a quick quiz competition is used to test their understanding of the numbers of the different products of this stage. This is just one of the range of methods that are used to check understanding and all answers are explained to allow students to assess their progress. This lesson has been written to tie in with the other uploaded lessons on glycolysis and the Krebs cycle and oxidative phosphorylation.

This fully-resourced lesson explores how other respiratory substrates, such as lipids and proteins, can be used to produce molecules of ATP. The PowerPoint and accompanying resources have been designed to cover the 7th and final part of point 5.2 of the AQA A-level Biology specification which states that students should know how these substrates enter the Krebs cycle. This lesson has been written to challenge the knowledge of the earlier parts of the topic of respiration and so contains constant prior knowledge checks which come in a range of forms. Students will learn that lipids and proteins can be used as respiratory substrates and will recognise the different ways that they enter the respiratory pathway. Time is taken to look at the beta oxidation pathway and again students are challenged to compare the products of this pathway against that of the Link reaction.

This fully-resourced lesson explores how pyruvate can be converted to lactate or ethanol using reduced NAD and that the reoxidation of the coenzyme allows glycolysis to continue. The engaging and detailed PowerPoint and accompanying differentiated resources have been designed to cover points 12.2 (j) and (k) of the CIE International A-level Biology specification which states that students should be able to explain the production of a small yield of ATP in anaerobic conditions and recognise the concept of an oxygen debt The lesson begins with a focus on the coenzyme, NAD, and students are challenged to recall details of its role in the oxidation of triose phosphate. Students will learn that oxidative phosphorylation in aerobic respiration allows these coenzymes to be reoxidised but that another metabolic pathway has to operate when there is no oxygen. Time is taken to go through the lactate and ethanol fermentation pathways and students are encouraged to discuss the conversions before applying their knowledge to complete diagrams and passages about the pathways. Understanding checks in a range of forms are used to enable the students to assess their progress whilst prior knowledge checks allow them to recognise the links to earlier topics. Students will also be introduced to the oxygen debt and will learn how the volume consumed after vigorous exercise is used to catabolise lactic acid and restore the body’s stores to normal levels. This lesson has been written to tie in with the other uploaded lessons on the stages of aerobic respiration.

This engaging and fully-resourced lesson looks at how genetic drift can arise after a genetic bottleneck or as a result of the Founder effect. The detailed PowerPoint and accompanying resources have been designed to cover point 17.2 © of the CIE International A-level Biology specification which states that students should be able to explain how the Founder effect and genetic drift may affect allele frequencies in populations. A wide range of examples are used to show the students how a population that descends from a small number of parents will have a reduction in genetic variation and a change in the frequency of existing alleles. Students are encouraged to discuss new information to consider key points and understanding checks in a range of forms are used to enable them to check their progress and address any misconceptions. Students are provided with three articles on Huntington’s disease in South Africa, the Caribbean lizards and the plains bison to understand how either a sharp reduction in numbers of a new population beginning from a handful of individuals results in a small gene pool. Links to related topics are made throughout the lesson to ensure that a deep understanding is gained.

This fully-resourced lesson guides students through the use of the Hardy-Weinberg equations to determine the frequency of alleles, genotypes and phenotypes in a population. Both the detailed PowerPoint and differentiated practice questions on a worksheet have been designed to cover point 17.2 (d) of the CIE International A-level Biology specification which states that students should be able to demonstrate and apply their knowledge and understanding of the use of the principle to calculate frequencies in populations. The lesson begins by looking at the two equations and ensuring that students understand the meaning of each of the terms. The recessive condition, cystic fibrosis, is used as an example so that students can start to apply their knowledge and assess whether they understand which genotypes go with which term. Moving forwards, a step-by-step guide is used to show students how to answer a question. Tips are given during the guide so that common misconceptions and mistakes are addressed immediately. The rest of the lesson gives students the opportunity to apply their knowledge to a set of 3 questions, which have been differentiated so that all abilities are able to access the work and be challenged.

This fully-resourced lesson looks at the external and internal structure of the mammalian heart and explains how the differences in the thickness of the chamber walls is related to function. The engaging and detailed PowerPoint and accompanying resources have been designed to cover points 8.2 (a) and (b) of the CIE International A-level Biology 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. As detailed in specification point (b), time is taken to ensure that students can explain why the atrial walls are thinner than the ventricle 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 topics 8.1 and 8.2 including those which have already been covered like circulatory systems as well as those which are upcoming such as the cardiac cycle. 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 REVISION lesson has been written to challenge the students on their knowledge of the content of topic 1 (Cell structure) of the CIE International A-level Biology specification. The PowerPoint and accompanying resources will motivate the students whilst they assess their understanding of the content and identify any areas which may require further attention. The wide range of activities have been written to cover as much of the topic as possible but the following specification points have been given particular focus: ATP is produced in mitochondria and chloroplasts and the role of ATP in cells Recognising eukaryotic cell structures and outlining their functions Calculating actual sizes from electron micrographs The structural features of a typical prokaryotic cell The key features of viruses as non-cellular structures Distinguish between resolution and magnification Quiz rounds such as “GUESS WHO of CELL STRUCTURES” and “YOU DO THE MATH” are used to test the students on the finer details of their knowledge of the structure and functions of the organelles and some key numerical facts