This lesson explains how uncontrolled cell division can lead to the formation of tumours and considers the differences between benign and malignant. The PowerPoint and accompanying resources have been planned to cover point 5.1 (6) of the CIE A-level biology specification (for assessment in 2025 - 2027), The lesson begins with the introduction of the meaning of the mitotic index as well as its formula and the students are then challenged to apply their understanding of this unfamiliar formula to a series of exam-style questions. This will challenge their mathematical skills along with the recollection of the details of the cell cycle that were met in the earlier lessons in topic 5.1. Moving forwards, the potential meanings of a high mitotic index are explored, including high rates of growth and tissue repair, before students are supported to understand that this could indicate that cell division has become uncontrolled. The key term tumour is revealed during a quick quiz round and then the remaining part of the lesson considers how benign and malignant tumours differ. Understanding checks and prior knowledge checks are found throughout the lesson and the answers are embedded into the PowerPoint to allow the students to assess their progress.

This lesson describes the simple reflex arc as a basis for rapid, involuntary and protective actions. The PowerPoint and accompanying resources have been designed to cover the content of point (d) of topic 8 of A2 unit 3 of the WJEC A-level biology specification. At the start of the lesson, the students are challenged to recognise the connections between three groups of key terms, and this acts to remind them of the sensory, motor and relay neurone, different types of muscle tissue and some reflexes. Time is taken to ensure that students understand that a simple spinal reflex arc is a direct neural pathway through the spinal cord and does not involve processing by the brain. Some of the content was covered at GCSE and in the first lessons of topic 8, so this lesson has been specifically planned to challenge their recall of this content and then to build upon it, and understanding and prior knowledge checks are used throughout to allow them to assess their progress. The students will be able to recognise the different matter of the spinal cord, which is named according to the presence of myelinated or unmyelinated neurones and they will also understand how sensory neurones enter via the dorsal root and motor neurones exit via the ventral root. Moving forwards, two examples of real biological reflexes are used to increase relevance, and students will see how the knee jerk reflex is unusual as it doesn’t contain a relay neurone. References to synapses, myelination and saltatory conduction are included in the lesson and brief details provided before these are covered in upcoming topic 8 lessons.

This clear and concise lesson explores the importance of coenzymes in cellular respiration as detailed in point 5.2.2 (f) of the OCR A-level Biology A specification. Students encountered coenzymes in module 2.1.4 as well as looking at the roles of NAD, CoA and FAD whilst learning about glycolysis, the link reaction and Krebs cycle earlier in this module. Therefore this lesson was designed to check on their understanding of the importance of these roles and goes on to explain how the transport of the protons and electrons to the mitochondrial cristae is key for the production of ATP. This lesson has been written to tie in with the other uploaded lessons in module 5.2.2 which include the mitochondria, glycolysis, the link reaction and the Krebs cycle

This fully-resourced lesson looks at the details of glycolysis as the first stage of 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 12.2 (b) of the CIE International A-level Biology specification which states that students should know glycolysis as the phosphorylation of glucose and the subsequent splitting into triose phosphate which is then oxidised to pyruvate. 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 engaging lesson looks at the role of haemoglobin in carrying oxygen and carbon dioxide. The PowerPoint has been designed to cover point 8.1 (f) of the CIE International A-level Biology specification and includes references to the role of carbonic anhydrase and the formation of haemoglobinic acid and carbaminohaemoglobin. The lesson begins with a version of the quiz show Pointless to introduce haemotology as the study of the blood conditions. Students are told that haemoglobin has a quaternary structure and are challenged to use their prior knowledge of biological molecules to determine what this means for the protein. They will learn that each of the 4 polypeptide chains contains a haem group with an iron ion attached and that it is this group which has a high affinity for oxygen. Time is taken to discuss how this protein must be able to load (and unload) oxygen as well as transport the molecules to the respiring tissues. Students will plot the oxyhaemoglobin dissociation curve and the S-shaped curve is used to encourage discussions about the ease with which haemoglobin loads each molecule. The remainder of the lesson looks at the different ways that carbon dioxide is transported around the body that involve haemoglobin. Time is taken to look at the dissociation of carbonic acid into hydrogen ions so that students can understand how this will affect the affinity of haemoglobin for oxygen in an upcoming lesson on the Bohr effect.

This fully-resourced lesson explores how the structure of arteries, veins and capillaries relates to their functions. The engaging and detailed PowerPoint and accompanying resources have been designed to cover point 1.3 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification. This lesson has been written to build on any prior knowledge from GCSE or earlier in this topic to enable students to fully understand why a particular type of blood vessel has particular features. Students will be able to make the connection between the narrow lumen and elastic tissue in the walls of arteries and the need to maintain the high pressure of the blood. A quick version of the GUESS WHO game is used to introduce smooth muscle and collagen in the tunica media and externa and again the reason for their presence is explored and explained. Moving forwards, the lesson considers the structure of the veins and students are challenged to explain how the differences to those observed in arteries is due to the lower blood pressure found in these vessels. The final part of the lesson looks at the role of the capillaries in exchange. Links are made to diffusion to ensure that students can explain how the red blood cells pressing against the endothelium results in a short diffusion distance. It is estimated that it will take about 2 hours of allocated A-level Biology teaching time to cover the detail included in this lesson

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 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 detailed lesson describes the fluid mosaic model of membrane structure and also describes the roles of its components. The detailed and engaging PowerPoint and accompanying worksheets have been designed to cover specification point 2.1.5 (b) of the OCR A-level Biology A specification and clear links are made to related topics such as the binding of peptide hormones The fluid mosaic model is introduced at the start of the lesson so that it can be referenced at appropriate points throughout the lesson. Students were introduced to phospholipids in module 2.1.2 and an initial task challenges them to spot the errors in a passage describing the structure and properties of this molecule. This reminds them of the bilayer arrangement, with the hydrophilic phosphate heads protruding outwards into the aqueous solutions on the inside and the outside of the cell. In a link to some upcoming lessons on the transport mechanisms, the students will learn that only small, non-polar molecules can move by simple diffusion and that this is through the tails of the bilayer. This introduces the need for transmembrane proteins to allow large or polar molecules to move into the cell by facilitated diffusion and active transport. Proteins that act as receptors as also introduced and an opportunity is taken to make a link to an upcoming topic so that students can understand how hormones or drugs will bind to target cells in this way. Moving forwards, the structure of cholesterol is covered and students will learn that this hydrophobic molecule sits in the middle of the tails and therefore acts to regulate membrane fluidity. The final part of the lesson challenges the students to apply their newly-acquired knowledge to a series of questions where they have to explain why proteins may have moved when two cells are used and to suggest why there is a larger proportion of these proteins in the inner mitochondrial membrane than the outer membrane.

This detailed lesson describes the properties of water to demonstrate the importance of this molecule for living organisms. The engaging PowerPoint and accompanying resource have been designed to cover the details of specification point (b) of AS unit 1, topic 1 of the WJEC A-level Biology course and has been specifically designed to ensure that each role is illustrated using a specific example. As this is only the second lesson in the biological compounds topic, 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: polarity ability to form hydrogen bonds surface tension as a solvent thermal properties as a metabolite The final part of the lesson introduces condensation and hydrolysis reactions and students will learn that a clear understanding of these reactions is critical as they will reappear throughout the topic in the synthesis and breakdown of biological compounds

This detailed lesson describes the importance of the dipole nature of water and its numerous properties to living organisms. The engaging PowerPoint and accompanying resource have been designed to cover the details of specification point 1.7 of the Edexcel A-level Biology B course and the intricate planning ensures that each role is illustrated using a specific example. As the final lesson in the biological molecules topic, not only does this lesson cover the important content related to water but also acts as a revision tool as it checks on key topic 1 content such as condensation and hydrolysis reactions. A wide range of tasks are used to check on current understanding and prior knowledge and quick quiz competitions 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: high specific heat capacity polar solvent surface tension incompressibility maximum density at 4 degrees Celsius

This engaging lesson describes how the structure and properties of phospholipids relate to their functions in cell membranes. The PowerPoint has been designed to cover point 1.2 (iv) as detailed in the Edexcel A-level Biology B specification and includes regular references to the previous lesson on triglycerides to check on knowledge and understanding The role of a phospholipid in a cell membrane provides the backbone to the whole lesson. A quick quiz round called family affair, challenges the students to use their knowledge of the structure of a triglyceride to identify the shared features in a phospholipid. This then allows the differences to be introduced, such as the presence of a phosphate group in place of the third fatty acid. Moving forwards, the students will learn that the two fatty acid tails are hydrophobic whilst the phosphate head is hydrophilic which leads into a key discussion point where the class has to consider how it is possible for the phospholipids to be arranged when both the inside and outside of a cell is an aqueous solution. The outcome of the discussion is the introduction of the bilayer which is critical for the lessons in topic 4 on the fluid mosaic model. The final part of the lesson explains how both facilitated diffusion and active transport mean that proteins are found floating in the cell membrane and this also helps to briefly prepare the students for upcoming topic 4 lessons.

This detailed and fully-resourced lesson describes the relationship between the structure and function of the polysaccharides: glycogen, starch and cellulose. The engaging PowerPoint and accompanying resources have been designed to cover point 1.1 (iv) as it is detailed in the Edexcel A-level Biology B specification and clear links are also made to the previous lessons in this topic where the monosaccharides and disaccharides were introduced. By the end of this lesson, students should understand how key structural features like the 1 - 4 and 1 - 6 glycosidic bonds and the hydrogen bonds dictate whether the polysaccharide chain is branched or unbranched and also whether it spirals or not. A range of activities are used to motivate and engage the students as they discover that glycogen is stored in liver and muscle cells, which it is able to do because of its compact structure. They are encouraged to discuss why the branched structure of this polysaccharide means that it can act as an immediate source of energy and they will recognise that hydrolysis reactions at the multiple ends of this chain will release glucose. Following on from the description of the structure of glycogen, students are challenged to design an exam question in the form of a comparison table so that it can be completed as the lesson progresses once they learn more about starch and cellulose. This includes a split in the starch section of the table so that the differing structures and properties of amylose and amylopectin can be considered. In the final part of the lesson, time is taken to focus on the formation of cellulose microfibrils and macrofibrils to explain how plant cells have the additional strength needed to support the whole plant. Due to the detail included in this lesson, it is estimated that it will take in excess of 2 hours of allocated teaching time to complete

This fully-resourced lesson describes the different effects that gene mutations can have on the amino acid sequence of a protein. The engaging and detailed PowerPoint and accompanying resources have been designed to cover points 1.4 (viii) & (ix) as detailed in the Edexcel A-level Biology B specification and includes substitutions, deletions and insertions and considers a real life example in sickle cell anaemia. In order to understand how a change in the base sequence can affect the order of the amino acids, students must be confident in their understanding and application of protein synthesis which was covered earlier in this topic. Therefore, the start of the lesson focuses on transcription and translation and students are guided through the use of the codon table to identify amino acids. Moving forwards, a task called known as THE WALL is used to introduce to the names of three types of gene mutation whilst challenging the students to recognise three terms which are associated with the genetic code. The main focus of the lesson is substitutions and how these mutations may or may not cause a change to the amino acid sequence. The students are challenged to use their knowledge of the degenerate nature of the genetic code to explain how a silent mutation can result. Students will learn that a substitution is responsible for the new allele that causes sickle cell anaemia and they are tested on their understanding through an exam-style question. As with all of the questions, a mark scheme is included in the PowerPoint which can be displayed to allow the students to assess their understanding. The rest of the lesson looks at base deletions and base insertions and students are introduced to the idea of a frameshift mutation. One particular task challenges the students to evaluate the statement that base deletions have a bigger impact on primary structure than base substitutions. This is a differentiated task and they have to compare the fact that the reading frame is shifted by a deletion against the change in a single base by a substitution

This fully-resourced lesson describes the relationship between the structure of the chloroplast and its role as the site of photosynthesis. The engaging PowerPoint and accompanying resources have been designed to cover specification point 5.7 (i) of the Edexcel A-level Biology B course. Students were introduced to the ultrastructure of eukaryotic cells in topic 2 so this lesson has been written to build on that knowledge. A version of the quiz show POINTLESS runs throughout the lesson and this maintains engagement whilst challenging the students to recall the parts of the chloroplast based on a description which is related to their function. The following structures are covered in this lesson: double membrane thylakoids (grana) stroma intergranal lamellae starch grains chloroplast DNA and ribosomes Once each structure has been recalled, a range of activities are used to ensure that key details are understood such as the role of the thylakoid membranes in the light-dependent stage and the importance of ATP and reduced NADP for the Calvin cycle. This lesson has been specifically written to prepare students for the upcoming lessons on the light-dependent stage and light-independent stage