This lesson describes the role of the cardiovascular control centre in the medulla oblongata in the control of heart rate. The engaging and detailed PowerPoint and accompanying resources have been designed to cover the first part of point 7.13 (ii) of the Edexcel International A-level Biology specification and explains how this regulation enables the rapid delivery of oxygen and the removal of carbon dioxide. This lesson begins with a prior knowledge check where students have to identify and correct any errors in a passage about the conduction system of the heart. This allows the SAN to be recalled as this structure play an important role as the effector in this control system. Moving forwards, the three key parts of a control system are recalled as the next part of the lesson will specifically look at the range of sensory receptors, the coordination centre and the effector. Students are introduced to chemoreceptors and baroreceptors and time is taken to ensure that the understanding of the stimuli detected by these receptors is complete and that they recognise the result is the conduction of an impulse along a neurone to the brain. A quick quiz is used to introduce the medulla oblongata as the location of the cardiovascular centre. The communication between this centre and the SAN through the autonomic nervous system can be poorly understood so detailed explanations are provided and the sympathetic and parasympathetic divisions compared. The final task challenges the students to demonstrate and apply their understanding by writing a detailed description of the control and this task has been differentiated three ways to allow differing abilities to access the work

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 the three main stages of the Calvin cycle as fixation, reduction and regeneration. The detailed PowerPoint and accompanying resources have been designed to cover the content of point 13.1 (g) of the CIE A-level Biology specification and detailed planning ensures that continual links are made to the previous lesson on the light-dependent stage so that students understand how the products of that stage, ATP and reduced NADP, 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 Calvin cycle. This immediately introduces RuBP, GP and TP 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 TP The use of the majority of the TP in the regeneration of RuBP A step-by-step guide, with discussion points where the class are given time to discuss the answer to selected questions, is used to show how 6 turns of the cycle are needed to form the TP 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 designed to cover the higher tier content of specification points 7.4 & 7.5 (The hormones involved in the stages of the menstrual cycle) which is found in topic 7 of the Edexcel 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. Students will learn about the different stages of the menstrual cycle including menstruation and ovulation and will see how FSH, oestrogen, LH and progesterone interact to control these stages. This lesson has been designed for GCSE-aged students who are taking the Edexcel 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 resource contains an engaging PowerPoint and an accompanying worksheet which together cover the content of specification point 5.3.7 (Negative feedback) as found on the AQA GCSE Biology & Combined Science higher tier specifications. Over the course of the lesson, students will learn about the effects of the release of adrenaline and thyroxine and will understand how the latter is controlled by negative feedback. Due to the obvious connection to the previously learned endocrine system topic, regular opportunities are taken to check on this prior knowledge and these work well with the understanding checks which allow the students to assess their progress. Quiz competitions which include SAY WHAT YOU SEE and FROM NUMBERS 2 LETTERS are used to introduce key terms and abbreviations in a fun and memorable way, whilst the key details of the content is always at the forefront of the design of the lesson. This lesson has been written for students studying the higher tier of the AQA GCSE Biology or Combined Science courses but it is also suitable for use with A-level students who need to recall the key details of these two hormones

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

This fully-resourced lesson 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 detailed lesson describes the formation of polypeptides as well as the different levels of protein structures and links this to function. Both the engaging PowerPoint and accompanying resources have been designed to cover points 2.9 (ii) & (iii) of the Pearson Edexcel A-level Biology A specification but also makes specific reference to genes and therefore covers the details of point 2.8 too. 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. The lesson concludes with one final task where the students have to identify three errors in a passage about the hydrolysis of a dipeptide or polypeptide.

This detailed and fully-resourced lesson describes the relationship between the structure and function of glycogen and starch. The engaging PowerPoint and accompanying resources have been designed to cover the fourth part of points 1.12 & 1.13 of the Pearson Edexcel A-level Biology A specification and clear links are also made to the previous lessons in this topic where the monosaccharides and disaccharides were introduced. The lesson begins with the CARBOHYDRATE WALL where students have to use their prior knowledge to collect the 9 carbohydrates on show into 3 groups. This results in glycogen, starch and cellulose being grouped together as polysaccharides and the structure and roles of the first two are covered over the course of the lesson. Students will learn 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 allows for spiralling. 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 and they learn more about starch. 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. The importance of the compact structure for storage is discussed as well as the branched chains of amylopectin acting as quick source of energy when it is needed. The lesson concludes with a question and answer section that guides the students when answering a question about the importance of the lower solubility of the polysaccharides when compared to the monosaccharides.

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 fully-resourced lesson guides students through the use of the Hardy-Weinberg equation to monitor changes in allele frequencies in a population. The detailed PowerPoint and differentiated practice questions worksheets have been designed to cover point 8.3 (iv) of the Edexcel A-level Biology B specification The lesson begins with a focus on the equation to ensure that the students understand the meaning of each of the terms. The recessive condition, cystic fibrosis, is used as an example so that students can start to apply their knowledge and assess whether they understand which genotypes go with which term. Moving forwards, a step-by-step guide is used to show students how to answer a question. Tips are given during the guide so that common misconceptions and mistakes are addressed immediately. The rest of the lesson gives students the opportunity to apply their knowledge to a set of 3 questions, which have been differentiated so that all abilities are able to access the work and be challenged

This fully-resourced lesson describes how selection pressures act on a gene pool and cause stabilising, directional and disruptive selection. The PowerPoint and accompanying resources have been designed to cover point 8.3 (i) of the Edexcel A-level Biology B specification which states that students should be able to identify each type of selection by its effect on different phenotypes. The lesson begins with an introduction to the mark, release, recapture method to calculate numbers of rabbits with different coloured fur in a particular habitat. This shows changes in numbers of the organisms and sketch graphs are then constructed to show these changes in the population size. A quick quiz competition is used to engage the students whilst introducing the names of the three main types of selection before a class discussion point encourages the students to recognise which specific type of selection is represented by the rabbits. Key terminology including intermediate and extreme phenotypes and selection pressure are used to emphasise their importance during explanations. A change in the environment of the habitat and a change in the numbers of the rabbits introduces directional selection before students will be given time to discuss and to predict the shape of the sketch graph for disruptive selection. Students are challenged to apply their knowledge in the final task of the lesson by choosing the correct type of selection when presented with details of a population and answer related questions.

This fully-resourced lesson describes the blood clotting process and includes the release of thromboplastin and the subsequent conversions to thrombin and fibrin. The engaging PowerPoint and accompanying worksheets have been primarily designed to cover the content detailed in point 1.6 of the Pearson Edexcel A-level Biology A specification but time has been taken to look at haemophilia as a sex-linked disease so that students are prepared for sex-linkage when covered in topic 3. The lesson begins with the introduction of clotting factors as integral parts of the blood clotting process and explains that factor III, thromboplastin, needs to recalled as well as the events that immediately precede and follows its release. Students will learn how damage to the lining and the exposure of collagen triggers the release of this factor and how a cascade of events then results. Quick quiz rounds and tasks are used to introduce the names of the other substances involved which are prothrombin, thrombin, fibrinogen and fibrin. In a link to the upcoming topic of proteins, students will understand how the insolubility of fibrin enables this mesh of fibres to trap platelets and red blood cells and to form the permanent clot. In the previous lessons, students described the events in atherosclerosis and a link is made to the role of blood clotting in CVD. The final part of the lesson introduces haemophilia as a sex-linked disease and students are challenged to apply their knowledge to an unfamiliar situation as they have to write genotypes and determine phenotypes before explaining why men are more likely to suffer from this disease than women.

This fully-resourced lesson describes how DNA is replicated semi-conservatively, including the roles of DNA helicase, polymerase and ligase. The detailed PowerPoint and accompanying resources have been designed to cover point 1.4 (ii) of the Edexcel A-level Biology B specification The main focus of this lesson is the roles of DNA helicase in the breaking of the hydrogen bonds between nucleotide bases, DNA polymerase in forming the growing nucleotide strands and DNA ligase in the joining of 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 and hydrolysis reactions through a range of exam questions and answers are displayed so that any misconceptions are quickly addressed. The main task of the lesson asks the students to use the information provided in the lesson to order the sequence of events in DNA replication before discussing how the presence of a conserved strand and a newly built strand in each new DNA molecule shows that it is semi-conservative.

This detailed lesson describes the process of translation at the ribosome and includes detailed descriptions of the roles of the mRNA, tRNA and rRNA. The PowerPoint and accompanying resources have been designed to cover the second part of point 1.4 (vi) of the Edexcel A-level Biology B specification and this lesson also includes continual links to the previous lessons in this topic on transcription and the structure of DNA and RNA. Translation is a topic which is often poorly understood and so this lesson has been written with the aim of supporting the students to answer the different types of questions that can arise. The lesson begins by challenging the students to consider why it is so important that the amino acids are assembled in the correct order during the formation of the chain. Moving forwards, a quick quiz round called “LOST IN TRANSLATION” is used to check on their prior knowledge of the mRNA strand, the tRNA molecules and the ribosomes. The next task involves a very detailed description of translation that has been divided into 14 statements which the students have to put into the correct order. By giving them a passage of this detail, they can pick out the important parts to use in the next task where they have to answer shorter questions worth between 3 and 4 marks. These types of questions are common in the assessments and by building up their knowledge across the lesson, their confidence to tackle this type of question should increase. The final two tasks of the lesson involve another quiz, where the teams compete to transcribe and translate in the quickest time before using all that they have absorbed to answer some questions which involve the genetic code and the mRNA codon table

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 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.

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 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 has been designed to cover both the foundation and higher tier content of specification point 5.3.2 (Control of blood glucose concentration) as found in topic 5 of the AQA GCSE Biology & Combined Science specifications. This resource contains an engaging PowerPoint (37 slides) and accompanying worksheets, some of which have been differentiated so that students of different abilities can access the work. The resource is filled with a wide range of activities, each of which has been designed to engage and motivate the students whilst ensuring that the key Biological content is covered in detail. Understanding checks are included throughout so that the students can assess their grasp of the content. In addition, previous knowledge checks make links to content from earlier topics such as the endocrine system and literacy checks ensure that the students can spell and recognise the key words, which is extremely important considering how many terms begin with the letter g in this homeostatic control system. The following content is covered in this lesson: The receptors, coordination centre and effectors in the control of blood glucose concentration The release of insulin when high blood glucose levels are detected The conversion of glucose to glycogen for storage in liver and muscle cells The causes and treatments of diabetes type I and II The release of glucagon when low blood glucose levels are detected The interaction of insulin and glucagon in a negative feedback cycle As stated at the top, this lesson has been designed for GCSE-aged students who are studying the AQA GCSE Biology or Combined Science courses, but it can be used with A-level students who need to go back over the key points before looking at the homeostatic control in more detail