This lesson describes how the products of the light-independent reactions of photosynthesis are used by plants, animals and other organisms. The engaging and detailed PowerPoint and accompanying resources have been primarily designed to cover point 5.4 (ii) of the Edexcel International A-level Biology specification concerning the uses of GP and GALP 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 1 and 2. The previous lesson described the light-independent reactions and this lesson builds on that understanding to demonstrate how the intermediates of the cycle, GP and GALP, 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 GALP 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 GALP 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 and the light-dependent and light-independent reactions of photosynthesis

This lesson describes how the critical evaluation of new data by the scientific community leads to new taxonomic groupings, like the three domains of life. The detailed PowerPoint and accompanying resources have been designed to cover point 4.14 (ii) of the Edexcel International A-level Biology specification and focuses on the introduction of the three-domain system following Carl Woese’s detailed study of the ribosomal RNA gene. The lesson begins with an introduction of Woese and goes on to describe how he is most famous for his definition of the Archaea as a new domain of life. Students were introduced to domains and the other classification taxa in a previous lesson, so their recall of this knowledge is continually tested and built upon as details are added. Students will discover the key differences between Archaea and Bacteria that led to the splitting of the prokaryotae kingdom and the addition of this higher classification rank. Moving forwards, the rest of the lesson describes how molecular phylogeny uses other molecules and that these are compared between species for classification purposes. One of these is a protein called cytochrome which is involved in respiration and can be compared in terms of primary structure to determine relationships. At this point in the lesson, the students are also tested on their knowledge of the nature of the genetic code (as covered in topic 2) and have to explain how mutations to DNA can also be used for comparative purposes.

This lesson describes how the action of the radial and circular muscles of the iris causes the pupil to dilate or contract. The PowerPoint has been designed to cover point 8.6 (ii) of the Edexcel International A-level Biology specification and includes key details such as the innervation of the smooth muscles by divisions of the autonomic nervous system. Students will learn how: the contraction of the radial muscles pulls the iris radially and enlarges the pupil, allowing more light to enter when an individual is in a room with dim light and that this contraction is the result of the conduction of an electrical impulse along a sympathetic motor neurone. the contraction of the circular muscles constricts the pupil to reduce the light that enters the eye, in order to prevent damage to the photosensitive cells in the retina. This is the result of innervation by an impulse conducted along a parasympathetic neurone

This fully-resourced lesson guides students through the principles of monohybrid inheritance, focusing on the importance of alleles. The PowerPoint and accompanying resources have been designed to cover points (a & b) in topic 3 of A2 unit 4 of the WJEC A-level Biology specification and includes the inheritance of alleles that demonstrate codominance. In order to minimise the likelihood of errors and misconceptions, step by step guides have been included throughout the lesson to support the students with the following: Writing parent genotypes Working out the different gametes that are made following meiosis Interpreting Punnett crosses to work out phenotypic ratios Students can often find pedigree trees the most difficult to interpret and to explain so exemplar answers are used as well as differentiated worksheets provided to support those students who need extra assistance

This fully-resourced lesson describes the roles of adrenaline in the fight or flight response. The engaging PowerPoint and accompanying resources have been designed to cover point 7.14 of the Edexcel International A-level Biology specification At the start of the lesson, the students have to use the knowledge acquired in the most recent lessons on the function of the heart to reveal the key term medulla and this leads into the description of the structure of the adrenal glands in terms of this inner region. The main part of the lesson focuses on the range of physiological responses of the organs to the release of adrenaline. Beginning with glycogenolysis, the need for adrenaline to bind to adrenergic receptors is described, including the activation of cyclic AMP. A quiz competition is used to introduce other responses including lipolysis, vasodilation, bronchodilation and an increase in stroke volume. Links to previous topics are made throughout the lesson and students are challenged on their knowledge of heart structure, triglycerides and polysaccharides.

This fully-resourced lesson describes the reactions of the light independent stage of photosynthesis that takes place in the chloroplast stroma. The detailed PowerPoint and accompanying resources have been designed to cover points 5.7 (iv, v & vi) of the Edexcel A-level Biology B specification and lengthy planning has ensured that links are continually made to the previous lesson on the light-dependent stage so that students can understand how the products of that stage are essential for the Calvin cycle The lesson begins with an existing 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 stage as well as upcoming lessons on the synthesis of organic molecules from GALP and limiting factors

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 describes the relationship between the structure of monosaccharides and their roles in living organisms. The detailed and engaging PowerPoint and accompanying resources have been designed to cover the second part of points 1.12 & 1.13 of the Pearson Edexcel A-level Biology A specification and looks at alpha-glucose, galactose, fructose, deoxyribose and ribose. 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. 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 but students do not need to consider the beta form until topic 4. The remainder of the lesson focuses on the roles of the 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

This lesson describes the importance of homeostasis using negative feedback control and also describes the meaning of positive feedback. The PowerPoint and accompanying resources have been designed to the content with point 9.1 of the Edexcel A-level Biology B specification and explains how this feedback control maintains systems within narrow limits but has also been planned to provide important details for upcoming topics such as osmoregulation, thermoregulation and the depolarisation of a neurone. The normal ranges for blood glucose concentration, blood pH and body temperature are introduced at the start of the lesson to allow students to recognise that these aspects have to be maintained within narrow limits. A series of exam-style questions then challenge their recall of knowledge from topics 1-8 to explain why it’s important that each of these aspects is maintained within these limits. The students were introduced to homeostasis at GCSE, so this process is revisited and discussed, to ensure that students are able to recall that this is the maintenance of a state of dynamic equilibrium. A quick quiz competition is used to reveal negative feedback as a key term and students will learn how this form of control reverses the original change and biological examples are used to emphasise the importance of this system for restoring levels to the limits (and the optimum). The remainder of the lesson explains how positive feedback differs from negative feedback as it increases the original change and the role of oxytocin in birth and the movement of sodium ions into a neurone are used to exemplify the action of this control system.

This lesson describes how the structures of the xylem vessels, sieve tube elements and companion cells relates to their functions. Both the engaging and detailed PowerPoint and accompanying resources have been designed to cover point 3.1.3 (b) [i] of the OCR A-level Biology A specification. The lessons begins by challenging the students to identify the substances that a plant needs for the cellular reactions, where they are absorbed and where these reactions occur in a plant. The aim of this task is to get the students to recognise that water and mineral ions are absorbed in the roots and needed in the leaves whilst the products of photosynthesis are in the leaves and need to be used all over the plant. Students will be reminded that the xylem and phloem are part of the vascular system responsible for transporting these substances and then the rest of the lesson focuses on linking structure to function. A range of tasks which include discussion points, exam-style questions and quick quiz rounds are used to describe how lignification results in the xylem as a hollow tube of xylem cells to allow water to move as a complete column. They will also learn that the narrow diameter of this vessel allows capillary action to move water molecules up the sides of the vessel. The same process is used to enable students to understand how the structures of the companion cells allows assimilates to be loaded before being moved to the sieve tube elements through the plasmodesmata. It is estimated that it will take in excess of 2 hours of A-level teaching time to cover the detail which has been written into this lesson

This detailed lesson describes osmosis as the movement of free water molecules through a partially permeable membrane, down the water potential gradient. The engaging PowerPoint and accompanying resources have been designed to cover the details of specification point 2.4 of the Edexcel International A-level Biology specification and also describes the effect of solutions of different water potentials on suspended animal and plant cells. It’s likely that students will have used the term concentration in their osmosis definitions at iGCSE, so the aim of the starter task is to introduce water potential to allow students to begin to recognise osmosis as the movement of water molecules from a high water potential to a lower potential, down the water potential gradient. Time is taken to describe the finer details of water potential to enable students to understand that 0 is the highest value (pure water) and that this becomes negative once solutes are dissolved. Exam-style questions are used throughout the lesson to check on current understanding as well as prior knowledge checks which make links to previously covered topics such as the lipid bilayer of the cell membrane. The remainder of the lesson focuses on the movement of water when animal and plant cells are suspended in hypotonic, hypertonic or isotonic solutions and the final appearance of these cells is described, including any issues this may cause.

This detailed lesson describes how the anti-sense strand of DNA is used as template to form messenger RNA (mRNA) during transcription. The PowerPoint and accompanying resource have been designed to cover the first part of point 1.4 (vi) as detailed in the Edexcel A-level Biology B specification. The lesson begins by challenging the students to recall that most of the nuclear DNA in eukaryotes does not code for polypeptides. This allows the promoter region and terminator region to be introduced, along with the structural gene. Through the use of an engaging quiz competition, students will learn that the strand of DNA involved in transcription is known as the anti-sense strand and the other strand is the sense strand. Links to previous lessons on DNA and RNA structure are made throughout and students are continuously challenged on their prior knowledge as well as they current understanding of the lesson topic. Moving forwards, the actual process of transcription is covered in a 7 step bullet point description where the students are asked to complete each passage using the information previously provided as well as their own biological knowledge. An exam-style question is used to check on their understanding before the final task of the lesson looks at the journey of mRNA to the ribosome for the next stage of translation.

This fully-resourced lesson guides students through the interpretation of genetic pedigree diagrams for the inheritance of a single gene. The clear PowerPoint and accompanying resources have been designed to cover point 2.13 (ii) of the Pearson Edexcel A-level Biology A specification and includes the inheritance of multiple allele characteristics as well as those that demonstrate codominance. In order to minimise the likelihood of errors and misconceptions, step by step guides have been included throughout the lesson to support the students with the following: Writing parent genotypes Working out the different gametes that are made following meiosis Interpreting Punnett crosses to work out phenotypic ratios Students can often find pedigree trees the most difficult to interpret and to explain so exemplar answers are used as well as differentiated worksheets provided to support those students who need extra assistance.

This fully-resourced lesson describes how cells become specialised through differential gene expression. The PowerPoint and accompanying resources have been designed to cover the details of point 3.19 of the Edexcel International A-level Biology specification. This is one of the more difficult concepts in this A-level course and therefore key points are reiterated throughout this lesson to increase the likelihood of student understanding and to support them when trying to make links to actual biological examples in living organisms. There is a clear connection to transcription and translation as covered in topic 2, so the lesson begins by reminding students that in addition to the structural gene in a transcription unit, there is the promotor region where RNA polymerase binds. Students are introduced to the idea of transcription factors and will understand how these molecules can activate or repress transcription by enabling or preventing the binding of the enzyme. At this point, students are challenged on their current understanding with a series of questions about DELLA proteins so they can see how these molecules prevent the binding of RNA polymerase. The final section of the lesson looks at one further example with oestrogen and the ER receptor and explains how the binding of this chemical results in the release of the inhibitor and the production of active mRNA.

This lesson describes the origin of phagocytes and the sequence of events that occur during the phagocytosis of pathogens. The engaging and detailed PowerPoint and accompanying resources have been designed to cover point 11.1 (a) of the CIE International A-level Biology specification and also includes an introduction to antigen-presentation so that the students are prepared for the next lesson on the role of T and B lymphocytes At the start of the lesson, the students are challenged to recall that cytosis is a suffix associated with transport mechanisms and this introduces phagocytosis as a form of endocytosis which takes in pathogens and foreign particles. This emphasis on key terminology runs throughout the course of the lesson and students are encouraged to consider how the start or end of a word can be used to determine meaning. The process of phagocytosis is then split into 5 key steps and time is taken to discuss the role of opsonins as well as the fusion of lysosomes and the release of lysozymes. A series of application questions are used to challenge the students on their ability to make links to related topics including an understanding of how the hydrolysis of the peptidoglycan wall of a bacteria results in lysis. Students will be able to distinguish between neutrophils and monocytes from a diagram and at this point, the role of macrophages and dendritic cells as antigen-presenting cells is described so that it can be used in the next lesson. The lesson concludes with a brief introduction to lymphocytes so that initial links between phagocytosis and the specific immune responses are made.

This lesson describes how the structures of the xylem vessels, sieve tube elements and companion cells relates to their functions. The PowerPoint and accompanying resources have been designed to cover points (m & q) in topic 3 of AS unit 2 of the WJEC A-level Biology specification. Please note that this lesson does not include light and electron microscope pictures, so teachers will have to source and add these in themselves. The lessons begins by challenging the students to identify the substances that a plant needs for the cellular reactions, where they are absorbed and where these reactions occur in a plant. The aim of this task is to get the students to recognise that water and mineral ions are absorbed in the roots and needed in the leaves whilst the products of photosynthesis are in the leaves and need to be used all over the plant. Students will be reminded that the xylem and phloem are part of the vascular system responsible for transporting these substances and then the rest of the lesson focuses on linking structure to function. A range of tasks which include discussion points, exam-style questions and quick quiz rounds are used to describe how lignification results in the xylem as a hollow tube of xylem cells to allow water to move as a complete column. They will also learn that the narrow diameter of this vessel allows capillary action to move water molecules up the sides of the vessel. The same process is used to enable students to understand how the structures of the companion cells allows assimilates to be loaded before being moved to the sieve tube elements through the plasmodesmata.

This clear and concise lesson covers the Link reaction and its site in the cell as detailed in point 5.2.2 (d) of the OCR A-level Biology A specification. The PowerPoint explains how the product of glycolysis, pyruvate, is decarboxylated and dehydrogenated and combined with coenzyme A to form acetyl coenzyme A which will then enter the Krebs cycle. 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 detailed lesson describes how urea is formed in the liver by deamination and then removed from the bloodstream by ultrafiltration at the kidney. The PowerPoint and accompanying resources have been designed to cover point 9.9 (ii) of the Edexcel A-level Biology B specification. The first part of the lesson describes how deamination and the ornithine cycle forms urea. Although the students are not required to know the details of the cycle, it is important that they are aware of how the product of deamination, ammonia, is converted into urea (and why). Moving forwards, the rest of the lesson has been written to allow the students to discover ultrafiltration as a particular function and to be able to explain how the mechanisms found in the glomerulus and the Bowman’s capsule control the movement of small molecules out of the blood plasma. Key terminology is used throughout and students will learn how the combination of the capillary endothelium and the podocytes creates filtration slits that allow glucose, water, urea and ions through into the Bowman’s capsule but ensure that blood cells and plasma proteins remain in the bloodstream. A number of quiz competitions are used to introduce key terms and values in a fun and memorable way whilst understanding and prior knowledge checks allow the students to assess their understanding of the current topic and to challenge themselves to make links to earlier topics. The final task of the lesson challenges the students to apply their knowledge by recognising substances found in a urine sample that shouldn’t be present and to explain why this would cause a problem

This fully-resourced lesson describes the structure and properties of the two isomers of glucose and ribose as examples of monosaccharides. The detailed and engaging PowerPoint and accompanying resources have been designed to cover specification point 2.1.2 (d) of the OCR A-level Biology A course and also looks at galactose, fructose and deoxyribose. 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. 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 which includes a series of understanding and application questions where the students are challenged to describe the role of ribose in RNA and to suggest why ribose could be considered to be an important molecule for active transport and muscle contraction.

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.