This fully-resourced lesson describes how DNA is replicated during interphase of the cell cycle and explains why it is known as semi-conservative replication. Both the detailed PowerPoint and accompanying resources have been designed to cover the details of point 2.1.3 (e) of the OCR A-level Biology A specification and the occurrence of spontaneous mutations is also discussed in the latter part of the lesson. As detailed in the specification, the focus of this lesson is the role of the enzymes DNA helicase and polymerase and students are also introduced to DNA ligase to enable them to understand how this enzyme functions to join the nucleic acid fragments. Time is taken to explain key details such as the assembly of strands in the 5’-to-3’ direction so that the continuous manner in which the leading strand is synthesised can be compared against that of the lagging strand. The students are constantly challenged to make links to previous topics such as DNA structure, phosphorylated nucleotides and hydrolysis reactions through a range of exam questions and answers are displayed so any misconceptions are quickly addressed. The final part of the lesson focuses on the occurrence of mistakes by DNA polymerase and also on the quantity of DNA in the cell following replication so that future links can be made to the cell cycle (as covered in module 2.1.6)

The range of exam questions, understanding checks and quiz competitions that have been written into this revision lesson will help to motivate and engage the students whilst they assess their understanding of the content found in topic 1.3 (Digestion and the digestive system in humans) of the WJEC GCSE Biology specification. The resource includes a detailed and engaging Powerpoint (51 slides) and an associated worksheet, which has been differentiated to help differing abilities to access the work. The range of activities have been designed to cover as much of the content as possible but the following sub-topics have been given particular attention: The movement of food by peristalsis The role of carbohydrase, protease and lipase enzymes in digestion The tests for the presence of starch and glucose The roles of the stomach and small intestine in digestion The function of bile in the break down of fats The need for a balanced diet and implication for health of excess sugar and salt in foods

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 1.2 (Respiration and the respiratory system in humans) of the WJEC GCSE Biology specification. The range of activities have been designed to cover as much of the content as possible but the following sub-topics have been given particular attention: The need and purpose of the respiratory system The function of the mucus and cilia in the trachea and the effect of smoking on these structures The structure of the alveolus and its blood supply The mechanisms of inspiration and expiration The process of aerobic respiration and the release of energy in the form of ATP Anaerobic respiration and the production of lactic acid

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 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 fully-resourced lesson explains how gene mutations can occur by substitution, deletion and insertion and explores how these base pair changes can affect the primary structure of the polypeptide and therefore the phenotype. The engaging and detailed PowerPoint and accompanying resources have been designed to cover point 16.2 (e) of the CIE International A-level Biology specification which states that students should understand how these mutations occur and can affect the phenotype. 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 taught in topic 6. 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 quick quiz competition is used to introduce the names of three types of gene mutation whilst challenging the students to recognise terms which are associated with the genetic code and were met in the previous lesson. The main focus of the lesson is base 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. 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 how the mechanisms of root pressure and transpiration pull move water upwards in the xylem to the leaves. The detailed PowerPoint and accompanying, differentiated resources have primarily been designed to cover the second part of point 7.2 [c] of the CIE International A-level Biology specification but also cover 7.2 [b] as the cohesion-tension theory and adhesion are described and explained. This lesson has been written to follow on from the end of the previous lesson, which finished with the description of the transport of the water and mineral ions from the endodermis to the xylem. Students are immediately challenged to use this knowledge to understand root pressure and the movement by mass flow down the pressure gradient. Moving forwards, time is taken to study the details of transpiration pull and the interaction between cohesion, tension and adhesion in capillary action is explained. Understanding is constantly checked through a range of tasks and prior knowledge checks are also written into the lesson to challenge the students to make links to previously covered topics such as the structure of the transport tissues. The final part of the lesson considers the journey of water through the leaf and ultimately out of the stomata in transpiration. A step by step guide using questions to discuss and answer as a class is used to support the students before the final task challenges them to summarise this movement through the leaf.

This engaging lesson presentation (48 slides) and associated worksheets uses exam questions with displayed mark schemes, quick tasks and quiz competitions to enable students to assess their understanding of the topics found within module B4 of the OCR Gateway A Combined Science specification. The topics which are specifically tested within the lesson include: Ecosystems, Competition and interdependence, The carbon cycle and Decomposers Students will enjoy the competitions such as "Number CRAZY" and "Take the HOTSEAT" whilst crucially being able to recognise those areas which need their further attention

This fully-resourced lesson has been designed to cover the content found in specification point 5.2.3 (The eye) of topic 5 of the AQA GCSE Biology specification. This resource contains an engaging and detailed PowerPoint (46 slides) and accompanying worksheets, some of which have been differentiated to help students of different abilities to take on the task. The lesson begins with a game of IMPOSSIBLE (shown in the picture) where students are challenged to pick out the names of the 7 structures of the eye which the specification states they have to be able to identify on a diagram. Students are given the functions of the cornea and the sclera to guide them at the start of the labelling task before they have to use their previous knowledge of the nervous system to write a function for the optic nerve. Literacy and numeracy skills are tested throughout the lesson and the next round of the quiz challenges them to use synonyms to recognise the key terms of adaptation and accommodation. Time is taken to focus on the process of accommodation so that students can see how the ciliary muscles and suspensory ligaments interact to change the shape of the lens and allow both near and distant objects to be seen clearly. This takes the lesson nicely into the next section where the conditions of myopia and hyperopia are considered. Again, the students are challenged on their recognition of Biology terminology to spot that these are the medical names for short and long-sightedness. Students are guided through the correction of myopia before being challenged to write a letter to the mother of a girl who suffers from hyperopia, explaining how the lens is used to correct the defect. As stated at the top, this lesson has been designed for GCSE-aged students who are studying the AQA GCSE Biology course, but can be used with younger students who are keen to learn about the eye or with A-level students who need to go back over the key points.

This lesson has been designed to cover the higher tier content of specification point 5.3.4 (Hormones in human reproduction) which is found in topic 5 of the AQA GCSE Biology & Combined Science specifications. A wide range of activities will engage and motivate the students whilst the content is covered in detail and understanding checks are included at regular points to enable the students to self-assess their new found knowledge. The following Biology is covered in this lesson: Reproductive hormones in the development of secondary sexual characteristics The role of testosterone as the main male reproductive hormone The role of oestrogen and progesterone in the repair and maintenance of the uterus lining The role of FSH and LH in the maturation of an egg and ovulation The interaction of these four hormones in the control of the menstrual cycle The final part of the lesson involves a number of questions where the students are challenged to apply their knowledge to unfamiliar situations This lesson has been designed for GCSE-aged students who are taking the AQA GCSE Biology or Combined Science course but it is also suitable for younger students who are looking into this topic as part of the reproduction module

This fully-resourced lesson explores sex-linkage and specifically the inheritance of sex-linked diseases in humans and then challenges the students to apply their knowledge to examples in other animals. The detailed PowerPoint and associated differentiated resources have been designed to cover the part of point 16.2 (b) of the CIE International A-level Biology specification which states that students should be able to use genetic diagrams to solve problems involving sex-linkage. Key genetic terminology is used throughout and the lesson begins with a check on their ability to identify the definition of homologous chromosomes. Students will recall that the sex chromosomes are not fully homologous and that the smaller Y chromosome lacks some of the genes that are found on the X. This leads into one of the numerous discussion points, where students are encouraged to consider whether females or males are more likely to suffer from sex-linked diseases. In terms of humans, the lesson focuses on haemophilia and red-green colour blindness and a step-by-step guide is used to demonstrate how these specific genetic diagrams should be constructed and how the phenotypes should then be interpreted. The final tasks of the lesson challenge the students to carry out a dihybrid cross that involves a sex-linked disease and an autosomal disease before applying their knowledge to a question about chickens and how the rate of feather production in chicks can be used to determine gender. All of the tasks are differentiated so that students of differing abilities can access the work and all exam questions have fully-explained, visual markschemes to allow them to assess their progress and address any misconception

This lesson focuses on the structure of RNA and specifically the similarities and differences between this nucleic acid and DNA. The engaging and detailed PowerPoint and accompanying resource have been designed to cover the second part of point 6.1 (b) of the CIE International A-level Biology specification which states that students should be able to describe the structure of this nucleic acid. Students were introduced to the detailed structure of a nucleotide and DNA in previous lessons, so this lesson is written to tie in with those and continuously challenge prior knowledge as well as the understanding of the current topic. The lesson begins with the introduction of RNA as a member of the family of nucleic acids and this enables students to recognise that this polynuclotide shares a number of structural features that were previously seen in DNA. A quiz round called “A FAMILY AFFAIR” is used to challenge their knowledge of DNA to recognise those features that are also found on RNA such as the chain of linked nucleotides, pentose sugars, nitrogenous bases and phosphodiester bonds. The next task pushes them to consider features that have not been mentioned and therefore are differences as they answer a structured exam-style question on how RNA differs from DNA. Students will learn that RNA is shorter than DNA and this leads into the final part of the lesson where mRNA and tRNA are introduced and again they are challenged to use the new information explain the difference in size. Brief details of transcription and then translation are provided so that students are prepared for the upcoming lessons on protein synthesis

This detailed lesson describes the fluid mosaic model of membrane structure and outlines the roles of the different components . Fully resourced, the PowerPoint and accompanying worksheets have been designed to cover specification point 4.1 (a) of the CIE International A-level Biology specification but as the membranes and target cells are discussed, points 4.1 (b) and © are also partially covered 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 topic 2 and so 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 lesson describes the formation of dipeptides & polypeptides and the different levels of protein structure. Both the engaging PowerPoint and accompanying resources have been designed to cover specification points 1.3 (ii), (iii) & (iv) of the Edexcel A-level Biology B specification and also makes continual links to previous lessons such as amino acids as well as to upcoming lessons like antibodies and enzymes so students can understand where proteins are involved. The start of the lesson focuses on the formation of a peptide bond during a condensation reaction so that students can understand how a dipeptide is formed and therefore how a polypeptide forms when multiple reactions occur. The main part of the lesson describes the different levels of protein structure. A step by step guide is used to demonstrate how the sequences of bases in a gene acts as a template to form a sequence of codons on a mRNA strand and how this is translated into a particular sequence of amino acids known as the primary structure. The students are then challenged to apply their understanding of this process by using three more gene sequences to work out three primary structures and recognise how different genes lead to different sequences. Moving forwards, students will learn how the order of amino acids in the primary structure determines the shape of the protein molecule, through its secondary, tertiary and quaternary structure and time is taken to consider the details of each of these. There is a particular focus on the different bonds that hold the 3D shape firmly in place and a quick quiz round then introduces the importance of this shape as exemplified by enzymes, antibodies and hormones. Students will see the differences between globular and fibrous protein and again biological examples are used to increase relevance. The lesson concludes with one final quiz round called STRUC by NUMBERS where the students have to use their understanding of the protein structures to calculate a numerical answer.

This fully-resourced lesson describes how post-transcriptional changes to mRNA enable 1 gene to give rise to multiple proteins. The detailed PowerPoint and accompanying resources have been designed to cover point 3.19 of the Edexcel International A-level Biology specification. The lesson begins with a knowledge recall as the students have to recognise the definition of a gene as a sequence of bases on a DNA molecule that codes for a sequence of amino acids in a polypeptide chain. This description was introduced in topic 2 and the aim of the start of the lesson is to introduce the fact that despite this definition, most of the nuclear DNA in eukaryotes doesn’t actually code for proteins. A quick quiz competition is then used to introduce exons as the coding regions within a gene before students are challenged to predict the name of the non-coding regions and then to suggest a function for these introns. Moving forwards, pre-mRNA as a primary transcript is introduced and students will learn that this isn’t the mature strand that moves off to the ribosome for translation. Instead, a process called splicing takes place where the introns are removed and the remaining exons are joined together. Another quick quiz round leads to an answer of 20000 and students will learn that this is the number of protein-coding genes in the human genome. Importantly, the students are then told that the number of proteins that are synthesised is much higher than this value and a class discussion period encourages them to come up with biological suggestions for this discrepancy between the two numbers. The lesson concludes with a series of understanding and application questions where students will learn that alternative splicing enables a gene to produce more than a single protein and that this natural phenomenon greatly increases biodiversity.

This detailed lesson introduces the 3 main principles of the cell theory and describes how cells are organised into tissues, organs and organ systems. The engaging PowerPoint and accompanying resources have been designed to cover points 2.1 (i) & (ii) of the Edexcel A-level Biology B specification. The cell theory is introduced at the start of the lesson and the 1st principle is immediately discussed to ensure that students are aware that all living organisms are made of cells. This principle is discussed with relation to viruses to enable students to understand that the lack of cell structure in a virus is one of the reasons that they are not considered to be living. The second principle states that the cell is the basic unit of structure and organisation and this leads into the main part of the lesson where specialised cells and their groupings into tissues are considered. Students are challenged to compare an amoeba against a human to get them to focus on the difference in the SA/V ratio. This acts as an introduction into the process of differentiation and a recognition of its importance for multicellular organisms. Students will discover that a zygote is a stem cell which can express all of the genes in its genome and divide by mitosis. Time is then taken to introduce gene expression as this will need to be understood in the later topics of the course. Moving forwards, the lesson uses 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 will understand why the shape and arrangement of these cells differ in the trachea and alveoli in line with function. The link between specialised cells and tissues is made at this point of the lesson with these examples of epithelium and students will also see how tissues are grouped into organs and then into organ systems. The third principle states that cells arise from pre-existing cells and this will be demonstrated later in topic 2 with mitosis and meiosis.

This engaging lesson describes how the structure of the mammalian lung is adapted for rapid gaseous exchange. The PowerPoint has been designed to cover point 2.1 (iii) of the Pearson Edexcel A-level Biology A 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 then 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 taken by air when moving into the lungs.

This fully-resourced lesson describes how isolation reduces gene flow between populations which leads to allopatric and sympatric speciation. The engaging PowerPoint and accompanying resources have been designed to cover point 5.24 of unit 4 of the Edexcel International A-level Biology specification and uses a range of real life examples to increase the relevance and to deepen student understanding 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 lesson describes the light-independent reactions of photosynthesis as the reduction of carbon dioxide using the products of the light-dependent reactions. The detailed PowerPoint and accompanying resources have been designed to cover point 5.4 (i) of the Edexcel International A-level Biology specification and this means that it describes carbon fixation in the Calvin cycle and the roles of GP, GALP, RuBP and RUBISCO. The lesson begins with an prior 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 reactions as well as the upcoming lesson on the products of the light-independent reactions.

This lesson describes the light-dependent reactions of photosynthesis, including cyclic and non-cyclic photophosphorylation. The detailed PowerPoint and accompanying resources have been designed to cover point 5.3 in unit 4 of the Edexcel International A-level Biology specification and therefore this lesson describes how light energy is trapped by exciting electrons in chlorophyll and the role of these electrons in generating ATP, reducing NADP in photophosphorylation and producing oxygen through photolysis of water. This is a topic which students tend to find difficult so this lesson has been intricately planned to walk them through each of the key reactions in the light-dependent stage. Time is taken to describe the roles of the major protein complexes that are embedded in the thylakoid membrane and this includes the two photosystems, the proton pump and ATP synthase. A series of exam-style questions have been written that link to other biological topics in this course such as cell structure and membrane transport as well as application questions to challenge them to apply their understanding. Some of these resources have been differentiated to allow students of differing abilities to access the work and to be pushed at the same time. Students will learn that there are two pathways that the electron can take from PSI and at the completion of the two tasks which describe each of these pathways, they will understand how ATP is generated in non-cyclic and cyclic fashion. The final task of the lesson asks them to compare these two forms of photophosphorylation to check that they understand when photolysis is involved and reduced NADP is formed. Due to the detail included in this lesson, it is estimated that it will take in excess of 2.5 hours of allocated A-level teaching time to complete