This fully-resourced lesson describes how a triglyceride is synthesised and explains how the structure of this lipid relates to its numerous roles. The engaging PowerPoint and accompanying worksheets have been designed to cover specification points 1.2 (i), (ii and (iii) as detailed in the Edexcel A-level Biology B specification and links are also made to related future topics such as the importance of the myelin sheath for the conduction of an electrical impulse. The lesson begins with a focus on the basic structure and roles of lipids, including the elements that are found in this biological molecule and some of the places in living organisms where they are found. Moving forwards, the students are challenged to recall the structure of the carbohydrates from earlier in topic 1 so that the structure of a triglyceride can be introduced. Students will learn that this macromolecule is formed from one glycerol molecule and three fatty acids and have to use their understanding of condensation reactions to draw the final structure. Time is taken to look at the difference in structure and properties of saturated and unsaturated fatty acids and students will be able to identify one from the other when presented with a molecular formula. The final part of the lesson explores how the various properties of a triglyceride mean that it has numerous roles in organisms including that of an energy store and source and as an insulator of heat and electricity.

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

This concise lesson describes the essential features of the alveolar epithelium as a surface over which gas exchange takes place. The engaging PowerPoint has been designed to cover the fourth part of point 3.2 of the AQA A-level Biology specification and also includes an introduction to ventilation which is covered in the following lesson. Gas exchange at the alveoli is a topic that was covered at GCSE so this lesson has been written to challenge the recall of that knowledge and to build on it. The main focus 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. Again, students will have met this in a lesson in topic 2 on specialised cells (and tissues) so a number of prior knowledge checks are used alongside current understanding checks. The following features of the alveolar epithelium are also covered: Surface area Moist lining Production of surfactant The maintenance of a steep concentration gradient As a constant ventilation supply is critical for the maintenance of the steep concentration gradient, the final part of the lesson considers the mechanism of ventilation to prepare the students for the next lesson.

This detailed lesson describes the differences between monosaccharides, disaccharides and polysaccharides. The PowerPoint and accompanying resource have been designed to cover point 1.1 (i) that’s detailed in the Edexcel A-level Biology B specification and the aim of this lesson is to provide the students with key details to prepare them for the upcoming lessons on the carbohydrate groups. The lesson begins with a made-up round of the quiz show POINTLESS, where students have to try to identify four answers to do with carbohydrates. In doing so, they will learn or recall that these molecules are made from carbon, hydrogen and oxygen, that they are a source of energy which can sometimes be rightly or wrongly associated with obesity and that the names of the three main groups is derived from the Greek word sakkharon. A number of quick quiz rounds have been written into the lesson to introduce key terms in a fun and memorable way and the first round allows the students to meet some of common monosaccharides. Moving forwards, students will learn that a disaccharide is formed when two of these monomers are joined together and they are then challenged on their knowledge of condensation reactions which were originally encountered during the lesson on water. Students will understand how multiple reactions and multiple glycosidic bonds will result in the formation of a polysaccharide and glycogen and starch are introduced as well as amylose and amylopectin as components of this latter polymer. The final part of the lesson considers how hydrolysis reactions allow polysaccharides and disaccharides to be broken back down into monosaccharides.

This fully-resourced lesson describes the beneficial, neutral and harmful effects of gene mutations on the primary structure of a polypeptide. The engaging and detailed PowerPoint and accompanying resources have been designed to cover point 6.1.1 (a) of the OCR A-level Biology A specification which states that students should be able to understand how substitutions, deletions and insertions change the base sequence and describe how this affects protein production and function. 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 in module 2.1.3. 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 terms which are associated with the genetic code and were met back in 2.1.3. 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 the key events that occur during the three stages of the cardiac cycle and relates these to the structure of the mammalian heart. The engaging and detailed PowerPoint and accompanying resources have been designed to cover point 1.8 of the Edexcel International A-level Biology specification As the structure of the heart was covered at iGCSE, 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. For example, time is taken to ensure that students can explain why the atrial walls are thinner than the ventricular 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 topic 1 including those which have already been covered like the blood vessels. 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. The next part of the lesson introduces the cardiac cycle through the use of quick quiz competition which generates the key term systole. Students will learn that there are three stages in the cycle are atrial and ventricular systole followed by cardiac diastole and that the uni-directional movement of blood during these stages is maintained by the atrioventricular and semi-lunar valves. This leads into the emphasis of the key point that pressure changes in the chambers and the major arteries is the cause of 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 rest 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. The final part of the lesson covers the changes in the volume of the ventricle. It is estimated that it will take in excess of 2 hours of allocated A-level teaching time to cover the detail included in this lesson as required by this specification point

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

This lesson describes how the hydrolysis of ATP provides energy for biological processes such as active transport and endocytosis and exocytosis. The PowerPoint and accompanying resources have been designed to cover points 4.2 (iv), (v) & (vi) of the Edexcel A-level Biology B specification The start of the lesson focuses on the structure of this energy currency and challenges the students to use their knowledge of nucleotides and specifically RNA nucleotides to recognise the components of ATP. As a result, they will learn that this molecule consists of adenine, ribose and three phosphate groups. In order to release the stored energy, ATP must be broken down and students will be given time to discuss which reaction will be involved as well as the products of this reaction. Time is taken to describe how the hydrolysis of ATP can be coupled to energy-requiring reactions and this leads into a series of exam-style questions where students are challenged on their knowledge of simple and facilitated diffusion to recognise that ATP is needed for active transport. These questions also challenge them to compare active transport against the forms of passive transport and to use data from a bar chart to support this form of transport. In answering these questions they will discover that carrier proteins are specific to certain molecules and time is taken to look at the exact mechanism of these transmembrane proteins. A quick quiz round introduces endocytosis and the students will see how vesicles are involved along with the energy source of ATP to move large substances in or out of the cell. The lesson concludes with a link to a future topic as the students are shown how exocytosis is involved in a synapse and in the release of ADH from the pituitary gland during osmoregulation.

This fully-resourced lesson describes the advantages of the double circulatory system that is found in mammals. The engaging PowerPoint and accompanying resources have been designed to cover point 4.4 (ii) of the Edexcel A-level Biology B specification and focuses on the differences in pressure between the pulmonary and systemic circulation. The lesson begins with a focus on the meaning of a double circulatory system and checks that students are clear in the understanding that the blood passes through the heart twice per cycle of the body. Beginning with the pulmonary circulation, students will recall that the pulmonary artery carries the blood from the right ventricle to the lungs. An opportunity is taken at this point to check on their knowledge of inhalation and the respiratory system as well as the gas exchange between the alveoli and the capillary bed. A quick quiz is used to introduce arterioles and students will learn that these blood vessels play a crucial role in the changes in blood pressure that prevent the capillaries from damage. When looking at the systemic circulation, time is taken to look at the coronary arteries and renal artery as students have to be aware of these vessels in addition to the ones associated with the heart. In the final part of the lesson, students are challenged to explain how the structure of the heart generates a higher pressure in the systemic circulation and then to explain why the differing pressures are necessary.

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

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

This fully-resourced lesson explores the effect of geographical and reproductive isolation on the evolution of a new species. The engaging PowerPoint and accompanying resources have been designed to cover point 6.1.2 (g) of the OCR A-level Biology A specification which states that students should be able to demonstrate and apply an understanding of the effect of these isolating mechanisms on the evolution of a new species by either allopatric or sympatric speciation. 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 has been written to tie in with the other uploaded lessons on topic 6.1.2 (patterns of inheritance).

This revision lesson contains an engaging and detailed powerpoint (58 slides) which is reinforced with a series of differentiated worksheets that are used throughout the lesson to challenge and consolidate the learning. The lesson has been designed to contain a wide range of activities so that students remain motivated and engaged whilst they assess their understanding of the content found in topic 3 (Infection and response) of the AQA GCSE Biology specification and will be covered in Paper 1 in the terminal GCSE exams. The exam questions, differentiated tasks and quiz competitions found within the lesson challenge the following specification topics: Communicable (infectious) diseases Viral diseases Bacterial diseases Fungal diseases Protist diseases Physical defences of the Human defence system Vaccinations Antibiotics Producing monoclonal antibodies Uses of monoclonal antibodies Identification of plant diseases Plant defence responses Students will be able to use the lesson to identify the areas of the specification that require further attention and this lesson can be used at the end of the topic, in the lead up to the mocks or in the lead up to the actual GCSE exams.

This fully-resourced lesson describes how TP is a starting material for the synthesis of carbohydrates, lipids and amino acids as well as being recycled to regenerate RuBP in the Calvin cycle. The engaging and detailed PowerPoint and accompanying resources have been primarily designed to cover point 5.2.1 (f) of the OCR A-level Biology A specification concerning the uses of TP but as the lesson makes continual references to biological molecules, it can act as a revision tool for the content of module 2.1.2. The previous lesson covered the light-independent stage and this lesson builds on that understanding to demonstrate how the product of the Calvin cycle, triose phosphate, is used. The start of the lesson challenges the students to identify two errors in a diagram of the cycle so that they can recall that most of the TP molecules are used in the regeneration of ribulose bisphosphate. A quiz version of Pointless runs throughout the lesson and this is used to challenge the students to recall a biological molecule from its description. Once each molecule has been revealed, time is taken to go through the details of the formation and synthesis of this molecule from TP or from GP in the case of fatty and amino acids. The following molecules are considered in detail during this lesson: glucose sucrose starch and cellulose glycerol and fatty acids amino acids nucleic acids A range of activities are used to challenge their prior knowledge of these molecules and mark schemes are always displayed for the exam-style questions to allow the students to assess their understanding. As detailed above, this lesson has been specifically written to tie in with the earlier lessons in this module on the structure of the chloroplast and the light-dependent and light-independent stages of photosynthesis.

This detailed lesson describes the transport of sodium and potassium ions in the maintenance of resting potential and how an action potential is formed. The engaging PowerPoint and accompanying resources have been designed to cover the detail included in points 9.5 (i) & (ii) of the Edexcel A-level Biology B specification. This topic is commonly assessed in the terminal exams so a lot of time has been taken to design this resource to include a wide range of activities that motivate the students whilst ensuring that the content is covered in the depth of detail that will allow them to have a real understanding. Interspersed within the activities are understanding checks and prior knowledge checks to enable the students to not only assess their progress against the current topic but also to challenge themselves on the links to earlier topics such as methods of movements across cell membranes. There are also a number of quiz competitions which are used to introduce key terms and values in a fun and memorable way and discussion points to encourage the students to consider why a particular process or mechanism occurs. Over the course of the lesson, the students will learn and discover how the movement of ions across the membrane causes the membrane potential to change. They will see how the resting potential is maintained through the use of the sodium/potassium pump and potassium ion leakage. There is a real focus on depolarisation to allow students to understand how generator potentials can combine and if the resulting depolarisation then exceeds the threshold potential, a full depolarisation will occur. At this point in the lesson students will discover how the all or nothing response explains that action potentials have the same magnitude and that instead a stronger stimulus is linked to an increase in the frequency of the transmission. The rest of the lesson challenges the students to apply their knowledge to explain how repolarisation and hyperpolarisation result and to suggest advantages of the refractory period for nerve cells.

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 the third part of point 1.2 of the AQA A-level Biology 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. Following 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 relationship between the structure and properties of triglycerides and considers their roles in living organisms. The engaging PowerPoint and accompanying worksheets have been designed to cover the first part of point 1.3 of the AQA A-level Biology specification and links are also made to related future topics such as the importance of the myelin sheath for the conduction of an electrical impulse. The lesson begins with a focus on the basic structure and roles of lipids, including the elements that are found in this biological molecule and some of the places in living organisms where they are found. Moving forwards, the students are challenged to recall the structure of the carbohydrates from topic 1.2 so that the structure of a triglyceride can be introduced. Students will learn that this macromolecule is formed from one glycerol molecule and three fatty acids and have to use their understanding of condensation reactions to draw the final structure. Time is taken to look at the difference in structure and properties of saturated and unsaturated fatty acids and students will be able to identify one from the other when presented with a molecular formula. The final part of the lesson explores how the various properties of a triglyceride mean that it has numerous roles in organisms including that of an energy store and source and as an insulator of heat and electricity.

This fully-resourced lesson describes the roles of the hypothalamus and the pituitary gland in the control of mammalian plasma concentration. The engaging PowerPoint and accompanying resources have been designed to cover point 7.21 of the Edexcel International A-level Biology specification The principles of homeostasis and negative feedback were covered in an earlier lesson in topic 7, so this lesson acts to build on that knowledge and challenges them to apply their knowledge. A wide range of activities have been included in the lesson to maintain motivation and engagement whilst the understanding and prior knowledge checks will allow the students to assess their progress as well as challenge themselves to make links to other Biology topics. The lesson begins with a discussion about how the percentage of water in urine can and will change depending on the blood water potential. Students will quickly be introduced to osmoregulation and they will learn that the osmoreceptors and the osmoregulatory centre are found in the hypothalamus. A considerable amount of time is taken to study the cell signalling between the hypothalamus and the posterior pituitary gland by looking at the specialised neurones (neurosecretory cells). Links are made to the topics of neurones, nerve impulses and synapses and the students are challenged to recall the cell body, axon and vesicles. The main section of the lesson forms a detailed description of the body’s detection and response to a low blood water potential. The students are guided through this section as they are given 2 or 3 options for each stage and they have to use their knowledge to select the correct statement. The final task asks the students to write a detailed description for the opposite stimulus and this task is differentiated so those who need extra assistance can still access the work.

This fully-resourced lesson describes the development of the humoral and cell-mediated immune responses. The detailed PowerPoint and accompanying resources have been designed to cover points 6.7 (ii) & (iii) as detailed in the Edexcel A-level Biology B specification and includes descriptions of the roles of antigen-presenting cells, T helper cells, cytokines, T killer cells, B cells, clonal selection and plasma cells. Antigen presentation was introduced at the end of the previous lesson so the task at the start of this lesson challenges students to recognise the name of this process and then they have to spot the errors in the passage that describes the details of this event. This reminds them that contact between the APC and T lymphocytes is necessary to elicit a response which they will come to recognise as the cell-mediated response. A series of quick quiz rounds reveals key terms in a memorable way and one that is introduced is helper T cells. Time is then taken to describe the importance of cell signalling for an effective response and students will learn how the release of chemicals by these cells activates other aspects of the response. The role of the killer T cells and their production of cytotoxins is also described before an exam-style question is used to check on their understanding at this point of the lesson. This leads into the section of the lesson that deals with the humoral response and students will understand how this involves the antibodies that are produced by the plasma cells that are the result of clonal selection and expansion. The T and B memory cells are also introduced so that students can understand how they are retained in the body even after the pathogen has been overcome and will play a critical role in the development of immunity. This prepares the students for the next lesson about the role of these memory cells in the secondary immune response.

This fully-resourced lesson describes the structure of the glucose and ribose as monosaccharides and considers their roles in living organisms. The detailed and engaging PowerPoint and accompanying resources have been designed to cover point 1.1 (ii) as detailed in the Edexcel A-level Biology B specification and also considers the structure of galactose, fructose and deoxyribose. Students were introduced to carbohydrates and monosaccharides in the previous lesson so this lesson builds on that initial understanding and adds key details to their knowledge of this simplest group. Using the molecular formula of glucose as a guide, students will be given the general formula for the monosaccharides and will learn that deoxyribose is an exception to the rule that the number of carbon and oxygen atoms are equal. Moving forwards, students have to study the displayed formula of glucose for two minutes without being able to note anything down before they are challenged to recreate what they saw in a test of their observational skills. At this point of the lesson, the idea of numbering the carbons is introduced so that the different glycosidic bonds can be understood in an upcoming lesson as well as the recognition of the different isomers of glucose. The difference between alpha and beta-glucose is provided and students are again challenged to draw a molecule of glucose, this time for the beta form. The remainder of the lesson focuses on the roles of the 6 monosaccharides and the final task involves a series of application questions where the students are challenged to suggest why ribose could be considered important for active transport and muscle contraction