This fully-resourced lesson guides students through the use of the Hardy-Weinberg equation to see whether a change in allele frequency is occurring in a population over time. The detailed PowerPoint and differentiated practice questions worksheets have been designed to cover point 4.5 (i) of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification which expects students to be able to use this mathematical equation The lesson begins by looking at the equation and ensuring that students understand the meaning of each of the terms. The recessive condition, cystic fibrosis, is used as an example so that students can start to apply their knowledge and assess whether they understand which genotypes go with which term. Moving forwards, a step-by-step guide is used to show students how to answer a question. Tips are given during the guide so that common misconceptions and mistakes are addressed immediately. The rest of the lesson gives students the opportunity to apply their knowledge to a set of 3 questions, which have been differentiated so that all abilities are able to access the work and be challenged

This highly detailed and engaging lesson which explains how a nerve impulse (action potential) is conducted along an axon). The PowerPoint and accompanying resources have been designed to cover point 8.3 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification which states that students should be able to describe how the changes in the membrane permeability to sodium and potassium ions results in conduction. 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 and saltatory conduction. 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 engaging lesson looks at the myogenic nature of cardiac muscle and explores the roles of the SAN, AVN, Bundle of His and Purkyne fibres in the normal electrical activity of the heart. The PowerPoint and accompanying resources have been designed to cover the points 7.8 (i & ii) of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification. The lesson begins with the introduction of the SAN as the natural pacemaker and then time is given to study each step of the conduction of the impulse as it spreads away from the myogenic tissue in a wave of excitation. The lesson has been written to make clear links to the cardiac cycle and the structure of the heart and students are challenged on their knowledge of this system from topic 1. Moving forwards, students are encouraged to consider why a delay would occur at the AVN and then they will learn that the impulse is conducted along the Bundle of His to the apex so that the contraction of the ventricles can happen from the bottom upwards. The structure of the cardiac muscle cells is discussed and the final task of the lesson challenges the students to describe the conducting tissue, with an emphasis on the use of key terminology Due to the detailed nature of this lesson, it is estimated that it will take about 2 hours of A-level teaching time to cover the two specification points

This fully-resourced lesson looks at how errors in DNA replication can give rise to gene mutations and then links to an earlier topic by exploring how these base changes can affect the primary structure of a polypeptide. The engaging and detailed PowerPoint and accompanying resources have been designed to cover point 2.12 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification and constantly refers back to points 2.7, 2.8 and 2.9 which detail the genetic code, genes and the structure of proteins. 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 2.6. 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 clear and concise lesson looks at the calculation of cardiac output as the product of stroke volume and heart rate. This engaging PowerPoint and accompanying resource have both been designed to cover point 7.9 (i) of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification which states that students should be able to calculate cardiac output. The lesson begins by challenging the students to recall that the left ventricle is the heart chamber with the thickest myocardial wall. This leads into the introduction of stroke volume as the volume of blood which is pumped out of the left ventricle each heart beat. A quick quiz game is used to introduce a normative value for the stroke volume and students are encouraged to discuss whether males or females would have higher values and to explain why. A second edition of this quiz reveals a normative value for resting heart rate and this results into the introduction of the equation to calculate cardiac output. A series of questions are used to challenge their ability to apply this equation and percentage change is involved as well. The final part of the lesson looks at the hypertrophy of cardiac muscle and students will look at how this increase in the size of cardiac muscle affects the three factors and will be challenged to explain why with reference to the cardiac cycle that was covered in an earlier topic.

This fully-resourced lesson looks at the roles of glycolysis in aerobic and anaerobic respiration and explains how the sequence of reactions results in glucose being converted to pyruvate. The engaging PowerPoint and accompanying differentiated resources have been designed to cover point 7.4 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification. The lesson begins with the introduction of the name of the stage and then explains how the phosphorylation of the hexoses and the production of the ATP, coenzymes and pyruvate are the stages that need to be known for this specification. Time is taken to go through each of these stages and key points such as the use of ATP in phosphorylation are explained so that students can understand how this affects the net yield. A quick quiz competition is used to introduce NAD and the students will learn that the reduction of this coenzyme, which is followed by the transport of the protons and electrons to the cristae for the electron transport chain is critical for the overall production of ATP. Understanding checks, in a range of forms, are included throughout the lesson so that students can assess their progress and any misconceptions are immediately addressed. This lesson has been written to tie in with the other uploaded lessons on the Link reaction, Krebs cycle, oxidative phosphorylation and the production of lactate.

This fully-resourced lesson looks at the series of oxidation-reduction reactions that form the Krebs cycle and focuses on the products in terms of reduced NAD, FAD and ATP. The engaging PowerPoint and accompanying resource have both been designed to cover the fifth part of point 5.2 of the AQA A-level Biology specification. The lesson begins with a version of the Impossible game where students have to spot the connection between 8 of the 9 terms and will ultimately learn that this next stage is called the Krebs cycle. The main part of the lesson challenges the students to use descriptions of the main steps of the cycle to continue their diagram of the reactions. Students are continually exposed to key terminology such as decarboxylation and dehydrogenation and they will learn where carbon dioxide is lost and reduced NAD and FAD are generated. They will also recognise that ATP is synthesised by substrate level phosphorylation. The final task challenges them to apply their knowledge of the cycle to work out the numbers of the different products and to calculate the number of ATP that must be produced in the next stage This lesson has been designed to tie in with the other uploaded lessons on glycolysis, anaerobic respiration, the Link reaction and oxidative phosphorylation.

This clear and concise lesson looks at the role of the Link reaction in the conversion of pyruvate to acetyl coenzyme A which will then enter the Krebs cycle. The PowerPoint has been designed to cover the fourth part of point 5.2 of the AQA A-level Biology specification which states that students should know about this conversion and the production of reduced NAD 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 lesson looks at the detailed structure of DNA and builds on the knowledge from topic 1 to explain how this nucleic acid differs in the nucleus, mitochondria and chloroplasts of eukaryotic cells and in prokaryotic cells. Both the engaging PowerPoint and accompanying resources have been designed to cover the first part of point 6.1 (b) of the CIE International A-level Biology specification. As well as focusing on the differences between the DNA found in these two types of cells which includes the length, shape and association with histones, the various tasks will ensure that students are confident to describe how this double-stranded polynucleotide is held together by hydrogen and phosphodiester bonds. These tasks include exam-style questions which challenge the application of knowledge as well as a few quiz competitions to maintain engagement.

This detailed lesson explains how the process of transcription results in the production of messenger RNA (mRNA). Both the detailed PowerPoint and accompanying resource have been designed to specifically cover the first part of point 6.2 (d) of the CIE International A-level Biology 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 template strand and the other strand is the coding 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. 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 lesson has been written to challenge all abilities whilst ensuring that the most important details are fully explained.

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

This detailed and engaging lesson looks at the culture of transformed host cells as an in vivo method to amplify DNA fragments. Both the PowerPoint and accompanying resources have been designed to cover the third part of point 8.4.1 of the AQA A-level Biology specification and ties in with the previous two lessons in this sub-topic on producing DNA fragments and the polymerase chain reaction. The lesson begins with the introduction of the terms transgenic and transformed. Students will learn that bacterial cells are the most commonly transformed cells so the next task challenges their recall of the structures of these cells so that plasmid DNA can be examined from that point onwards. A quick quiz competition is used to introduce the key term, vector, and then the rest of the lesson looks at the details of the five steps involved in the transformation of the host cell: Remove and prepare the plasmid to act as a vector Insert the DNA fragment into the vector Transfer the recombinant plasmid into the host cell Identify the cells which have taken up the recombinant plasmid All the transformed host cells to replicate and express the novel gene Time is taken to explore the finer details of each step such as the addition of the promoter and terminator regions, use of the same restriction enzyme to cut the plasmid as was used to cut the gene and the different types of marker genes. Links are continuously made to the previous lessons in this topic so that students feel confident to answer assessment questions which bring in knowledge from all of the sections.

This detailed lesson describes the role of the mRNA, tRNA, amino acids and the ribosome during the second stage of protein synthesis - translation. Both the PowerPoint and accompanying resources have been designed to cover the third part of point 4.2 of the AQA A-level Biology specification and ties in with the previous lessons in this topic on RNA and transcription. Translation is a topic which is often poorly understood and so this lesson has been written to enable the students to understand how to answer the different types of questions by knowing and including the key details of the structures involved. 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, the genetic code 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 that consists of this considerable 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 through the lesson, their confidence to answer this type 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 learnt to answer some questions which involve the genetic code and the mRNA codon table.

This detailed lesson describes the role of the strand of mRNA, the tRNA molecules, the amino acids and the ribosome during the second stage of protein synthesis - translation. Both the PowerPoint and accompanying resources have been designed to cover the second part of point 6.2 (d) of the CIE International A-level Biology specification and ties in with the first part of this specification point which covered transcription. Translation is a topic which is often poorly understood and so this lesson has been written to enable the students to understand how to answer the different types of questions by knowing and including the key details of the structures involved. 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, the genetic code 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 that consists of this considerable 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 through the lesson, their confidence to answer this type should increase. The final two tasks of the lesson involve another quiz called “The protein synthesis game”, where the teams compete to transcribe and translate in the quickest time before using all the information from the lessons on protein synthesis to answer some questions which involve the genetic code and the mRNA codon table.

This engaging lesson describes the relationship between the structure and properties of a phopholipid and explains the link to its role in membranes. The PowerPoint has been designed to cover the second part of point 1.3 of the AQA A-level Biology specification and includes constant references to the previous lesson on triglycerides. The role of a phospholipid in a cell membrane provides the backbone to the whole lesson. A quick quiz round called FAMILY AFFAIR, challenges the students to use their knowledge of the structure of a triglyceride to identify the shared features in a phospholipid. This then allows the differences to be introduced, such as the presence of a phosphate group in place of the third fatty acid. Moving forwards, the students will learn that the two fatty acid tails are hydrophobic whilst the phosphate head is hydrophilic which leads into a key discussion point where the class has to consider how it is possible for the phospholipids to be arranged when both the inside and outside of a cell is an aqueous solution. The outcome of the discussion is the introduction of the bilayer which is critical for the lesson in topic 2 on the fluid mosaic model. The final part of the lesson explains how both facilitated diffusion and active transport mean that proteins are found floating in the cell membrane and this also helps to briefly prepare the students for upcoming topic 2 lessons.

Disaccharides are formed from the condensation of two monosaccharides and this lesson describes the formation of maltose, sucrose and lactose. The PowerPoint and accompanying question sheet have been designed to cover the second part of point 1.2 of the AQA A-level Biology specification but also make links to the previous lesson on monosaccharides when considering the different components of these three disaccharides. The first section of the lesson focuses on a prefix and a suffix so that the students can recognise that the names of the common disaccharides end in -ose. In line with this, a quick quiz round is used to introduce maltose, sucrose and lactose before students are challenged on their prior knowledge as they have to describe how condensation reactions and the formation of glycosidic bonds were involved in the synthesis of each one. The main task of the lesson again challenges the students to recall details of a previous lesson as they have to identify the monomers of each disaccharide when presented with the displayed formula. Time is taken to show how their knowledge of these simple sugars will be important in later topics such as digestion, translocation in the phloem and the Lac Operon in the control of gene expression. The lesson finishes with two exam-style questions where students have to demonstrate and apply their newly acquired knowledge