This lesson explains the effects of temperature on the rate of enzyme activity and includes examples in plants, animals and microorganisms. The PowerPoint and the accompanying resource have been designed to cover point 5.16 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification and this lesson has been specifically planned to tie in with a lesson in topic 2 where the roles and mechanism of action of enzymes were introduced. The lesson begins by challenging the students to recognise optimum as a key term from its 6 synonyms that are shown on the board. Time is taken to ensure that the students understand that the optimum temperature is the temperature at which the most enzyme-product complexes are produced per second and therefore the temperature at which the rate of an enzyme-controlled reaction works at its maximum. The optimum temperatures of DNA polymerase in humans and in a thermophilic bacteria and RUBISCO in a tomato plant are used to demonstrate how different enzymes have different optimum temperatures and the roles of the former in the PCR is briefly described to prepare students for this lesson in topic 6. Moving forwards, the next part of the lesson focuses on enzyme activity at temperatures below the optimum and at temperatures above the optimum. Students will understand that increasing the temperature increases the kinetic energy of the enzyme and substrate molecules, and this increases the likelihood of successful collisions and the production of enzyme-substrate and enzyme-product complexes. When considering the effect of increasing the temperature above the optimum, continual references are made to the previous lesson and the control of the shape of the active site by the tertiary structure. Students will be able to describe how the hydrogen and ionic bonds in the tertiary structure are broken by the vibrations associated with higher temperatures and are challenged to complete the graph to show how the rate of reaction decreases to 0 when the enzyme has denatured.

This lesson describes the classification of species into the taxonomic hierarchy and cover point 18.2 (a) of the CIE A-level Biology specification. The engaging PowerPoint and accompanying resources have been designed to show students how the domain, kingdom, phylum, class, order, family, genus and species are used in modern-day classification. The lesson begins by with a knowledge recall as students have to use the provided information about a mule to explain why a horse and donkey are considered to be members of different species. Moving forwards, students will learn that species is the lowest taxon in the modern-day classification hierarchy. The first of a number of rounds of a competition is used to engage the students whilst they learn the names of the 7 other taxa and the horse and the donkey from the earlier example are used to complete the hierarchy. Students are told that a binomial naming system is used in Biology to provide a universal name for each species and the final task of the lesson challenges them to apply their knowledge by completing a hierarchy for a modern-day human, by spotting the correct name for an unfamiliar organism

This lesson explains the importance of memory cells in the development of immunity and describes how the structure of antibodies is related to function. The PowerPoint and accompanying resources have been designed to cover specification points 11.1 (e) and 11.2 (a) as detailed in the CIE A-level Biology specification. As memory B cells differentiate into plasma cells that produce antibodies when a specific antigen is re-encountered, it was decided to link these two topic points in one lesson. The lesson begins by checking on the students incoming knowledge to ensure that they recognise that B cells differentiate into plasma cells and memory cells. This was introduced in a previous lesson on the specific immune response and students must be confident in their understanding if the development of immunity is to be understood. A couple of quick quiz competitions are then used to introduce key terms so that the structure of antibodies in terms of polypeptide chains, variable and constant regions and hinge regions are met. Time is taken to focus on the variable region and to explain how the specificity of this for a particular antigen allows neutralisation and agglutination to take place. The remainder of the lesson focuses on the differences between the primary and secondary immune responses and a series of exam-style questions will enable students to understand that the quicker production of a greater concentration of these antibodies in the secondary response is due to the retention of memory cells.

This lesson describes the structure and function of synapses in nerve impulse transmission and focuses on acetylcholine as a neurotransmitter. The PowerPoint and accompanying resources have been designed to cover point 8.6 (i) of the Edexcel International A-level Biology specification, using a cholinergic synapse as the main example The lesson begins by using a version of the WALL from “Only Connect” which asks the students to group 12 words into three groups of 4. Not only will this challenge their prior knowledge from topics earlier in this topic but it will also lead to the discovery of four of the structures that are found in a synapse. Moving forwards, students are introduced to acetylcholine as the neurotransmitter involved at cholinergic synapses and they will start to add labels to the structures found in the pre-synaptic bulb. Time is taken to focus on certain structures such as the voltage gated channels as these types of channel were met previously when looking at the depolarisation of a neurone. There is plenty of challenge and discovery as students are pushed to explain why organelles like mitochondria would be found in large numbers in the bulb. With this process being a cascade of events, a bullet point format is used to ensure that the key content is taken in by the students and again key points like exocytosis and the action of acetylcholinesterase are discussed further. Understanding checks and prior knowledge checks are included throughout the lesson so that students can not only assess their progress against the current topic but also see whether they can make links to earlier topics.

This lesson describes the Krebs cycle as a stage of aerobic respiration that liberates energy to produce ATP and reduced NAD and releases carbon dioxide. The PowerPoint and accompanying resource have been designed to cover specification point [c] in topic 3 of A2 unit 3 of the WJEC 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 and the electron transport chain (in oxidative phosphorylation).

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 REVISION lesson has been written to challenge the students on their knowledge of the content of topic 1 (Cell structure) of the CIE International A-level Biology specification. The PowerPoint and accompanying resources will motivate the students whilst they assess their understanding of the content and identify any areas which may require further attention. The wide range of activities have been written to cover as much of the topic as possible but the following specification points have been given particular focus: ATP is produced in mitochondria and chloroplasts and the role of ATP in cells Recognising eukaryotic cell structures and outlining their functions Calculating actual sizes from electron micrographs The structural features of a typical prokaryotic cell The key features of viruses as non-cellular structures Distinguish between resolution and magnification Quiz rounds such as “GUESS WHO of CELL STRUCTURES” and “YOU DO THE MATH” are used to test the students on the finer details of their knowledge of the structure and functions of the organelles and some key numerical facts

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 5 (Enzymes) of the CIE IGCSE Biology specification for examination in June and November 2020 and 2021. This revision resource contains an engaging PowerPoint (25 slides) and 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: Define enzymes as proteins that function as biological catalysts Explain enzyme action with reference to active site, substrate and enzyme-substrate complex Explain the specificity of enzymes Explain the effect of changes of temperature on enzyme activity Explain the effect of changes of pH on enzyme activity Describe what happens to an enzyme when it is denatured

This lesson explains the principles of the polymerase chain reaction (PCR) and the PowerPoint has been designed to cover point 6.1.3 (d) of the OCR A-level Biology A specification A quick quiz competition is used to introduce the PCR abbreviation before students are encouraged to discuss the possible identity of the enzyme involved and to recall the action of this enzyme. Students will learn that this reaction involves cyclical heating and cooling to a range of temperatures so the next part of this lesson focuses on each temperature and specifically the reasons behind the choice. Time is taken to examine the key points in detail, such as why Taq polymerase has to be used as it is not denatured at the high temperature as well as the involvement of the primers. This process is closely linked to other techniques like electrophoresis which is covered in a later lesson and ties are continuously made throughout the lesson This process is mentioned in other uploaded lessons in this module such as electrophoresis and genetic engineering to allow students to understand how it is critical for DNA analysis

This lesson describes the effects of pH on the rate of an enzyme-catalysed reaction. The PowerPoint and accompanying resources are part of the second lesson in a series of 4 lessons which have been designed to cover the content of point 3.2 (a) of the CIE A-level Biology specification. The lesson begins with a short discussion, where the students are challenged to identify how the stomach and the small intestine differ in terms of a particular condition and to explain why the conditions in these neighbouring digestive organs are so important. This introduces pepsin and trypsin and these protease enzymes play a key role throughout the lesson as they are good examples of how different extracellular enzymes have different optimum pH values (which are not necessarily 7.0). Moving forwards, students will discuss how the rate of an enzyme-controlled reaction will change if there are small or large changes in pH, and then time is taken to ensure that students can explain these changes with reference to tertiary structure bonds and the shape of the active site. Through the use of a quick quiz competition, the students will be reminded of the key term “buffer” and a series of questions are used to challenge their understanding of how these substances could be used in a practical investigation. They will also learn how buffers are found in blood plasma as well as in red blood cells in the form of haemoglobin. As there is a considerable proportion of marks for Maths in a Biology context questions in the A-level assessments, the remainder of the lesson challenges the students to use a given formula to calculate the pH of blood when given the hydrogen ion concentration and to calculate percentage decrease. These questions have been differentiated to give assistance to those that need the support

This lesson describes how the hydrolysis of ATP supplies energy for biological processes and how the phosphorylation of ADP requires energy. The PowerPoint has been designed to cover point 5.6 of the Pearson Edexcel A-level Biology A specification and also describes how ATP is made in the light-dependent stage of photosynthesis and is needed in the light-independent stage. 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 within cells and the examples of skeletal muscle contraction are used as this is covered in greater detail in topic 7. The final part of the lesson considers how ATP is formed when ADP is phosphorylated and students will learn that this occurs in the mitochondria and chloroplast during aerobic respiration and photosynthesis respectively, so that it ties in with the upcoming lessons in topic 5 and 7.

This fully-resourced lesson describes the ultrastructure of a prokaryotic cell including the nucleoid, plasmid, 70S ribosomes and cell wall. The engaging PowerPoint and accompanying resources have been designed to cover specification point 2.1 (iii) of the Edexcel A-level Biology B specification but has been specifically designed to be taught after the lesson on the ultrastructure of eukaryotic cells, specification point 2.1 (v), so that comparisons can be drawn. A clear understanding of terminology is important for A-level Biology so this lesson begins with a challenge, where the students have to come up with a 3-letter prefix that they believe will translate as before or in front of . This leads into the discovery of the meaning of prokaryote as before nucleus which acts to remind students that these types of cell lack this cell structure. Links to the previous lessons on the eukaryotic cells are made throughout the lesson and at this particular point, the students are asked to work out why the DNA would be described as naked and to state where it will be found in the cell. Moving forwards, the students will discover that these cells also lack membrane bound organelles and a quick quiz competition challenges them to identify the specific structure that is absent from just a single word. In addition to the naked DNA, students will learn that there are also ribosomes in the cytoplasm and will discover that these are smaller than those found in the cytoplasm of an eukaryotic cell (but the same size as those in chloroplasts and mitochondria). The remainder of the lesson focuses on the composition of the cell wall, the additional features of prokaryotic cells such as plasmids and there is also the introduction of binary fission as the mechanism by which these organisms reproduce so that students can recognise that prokaryotic cells do not contain centrioles

This fully-resourced lesson describes the effects of enzyme and substrate concentration on the rate of enzyme-catalysed reactions. The PowerPoint and accompanying resources are the third in a series of 4 lessons which cover the details of point 3.2 (a) of the CIE A-level Biology specification. The first part of the lesson describes how an increase in substrate concentration will affect the rate of reaction when a fixed concentration of enzyme is used. Time is taken to introduce limiting factors and students will be challenged to identify substrate concentration as the limiting factor before the maximum rate is attained and then they are given discussion time to identify the possible factors after this point. A series of exam-style questions are used throughout the lesson and the mark schemes are displayed to allow the students to assess their understanding and for any misconceptions to be immediately addressed. Moving forwards, the students have to use their knowledge of substrate concentration to construct a graph to represent the relationship between enzyme concentration and rate of reaction and they have to explain the different sections of the graph and identify the limiting factors. The final section of the lesson describes how the availability of enzymes is controlled in living organisms. Students will come to recognise that this availability is the result of enzyme synthesis and enzyme degradation and a series of tasks will introduce the details of transcription and translation and therefore prepare them for the lessons in topic 6. Please note that this lesson explains the Biology behind the effect of concentration on enzyme-catalysed reactions and not the methodology involved in carrying out such an investigation as this is covered in a core practical lesson.

This lesson describes the relationship between gross and net primary productivity and plant respiration and explains how to calculate NPP. The PowerPoint and accompanying resources have been designed to cover points 5.10 (i) and (ii) of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification. Due to the fact that the productivity of plants is dependent on photosynthesis, a series of exam-style questions have been written into the lesson which challenge the students to explain how the structure of the leaf as well as the light-dependent and light-independent reactions are linked to GPP. All of the exam questions have displayed mark schemes which are included in the PowerPoint to allow students to immediately assess their understanding. A number of quick quiz competitions as well as guided discussion points are used to introduce the formulae to calculate NPP and N and to recognise the meaning of the components. Once again, this is immediately followed by the opportunity to apply their understanding to selected questions. As well as linking to photosynthesis from earlier in topic 5, this lesson has been specifically planned to challenge students on their understanding of ecosystem terminology from the start of the topic as well as preparing them for the next lesson on the efficiency of biomass and energy transfer

This lesson describes the development and spread of antibiotic resistance in bacteria and discusses the difficulties in controlling this spread. The PowerPoint and accompanying worksheet have been designed to cover specification points 6.4 (i & ii) of the Edexcel A-level Biology B specification President Trump’s error ridden speech about antibiotics is used at the beginning of the lesson to remind students that this is a treatment for bacterial infections and not viruses as he stated. Moving forwards, 2 quick quiz competitions are used to introduce MRSA and then to get the students to recognise that they can use this abbreviation to remind them to use mutation, reproduce, selection (and survive) and allele in their descriptions of the development of resistance by evolution through natural selection. The main task of the lesson challenges the students to form a description to explain how this strain of bacteria developed resistance to methicillin, making use of the five key terms emphasised above. Moving forwards, there is a focus on the hospital as the common location for MRSA infections and students will recognise that this opportunistic pathogen can infect through open wounds to cause sepsis and potentially death. Figures from infections and deaths in hospitals in the US are used to increase the relevance and students will learn how a MRSA prevention program in VHA facilities includes screening of surgery patients to try to reduce its impact. The lesson concludes with a discussion about other methods that can be used by hospitals and general practitioners to reduce the spread of MRSA and to try to prevent the development of resistance in other strains.

This lesson describes how the relationship between the different properties of water and its roles in living organisms. The engaging PowerPoint has been designed to cover specification point 2.3 (d) of the CIE International A-level Biology course. Hydrolysis reactions have been a recurring theme throughout topic 2, so the start of this lesson challenges the students to recognise the definition when only a single word is shown: water. Students will also recall the meaning of a condensation reaction. Moving forwards, the rest of the lesson focuses on the relationship between the structure and properties of water, beginning with its role as an important solvent. The lesson has been specifically written to make links to future topics and this is exemplified by the transport of water along the xylem in plants which is covered in topic 7. The next section focuses on the high latent heat of vaporisation and heat capacity of water and these properties are put into biological context using thermoregulation and the maintenance of a stable environment for aquatic animals. The lesson finishes with an explanation of the polar nature of water, a particularly important property that needs to be well understood for a number of upcoming topics, such as cell membranes.

This lesson describes the structure of an amino acid and the formation and breakage of a peptide bond. The PowerPoint has been designed to cover specification point 2.3 (a) of the CIE International A-level Biology course and provides a clear introduction to the following lesson on the formation of dipeptides and polypeptides. The lesson begins with a prior knowledge check, where the students have to use the 1st letters of 4 answers to uncover a key term. This 4-letter key term is gene and the lesson begins with this word because it is important for students to understand that these sequences of bases on DNA determine the specific sequence of amino acids in a polypeptide. Moving forwards, students are given discussion time to work out that there are 64 different DNA triplets and will learn that these encode for the 20 amino acids that are common to all organisms. The main task of the lesson is an observational one, where students are given time to study the displayed formula of 4 amino acids. They are not allowed to draw anything during this time but will be challenged with 3 multiple choice questions at the end. This task has been designed to allow the students to visualise how the 20 amino acids share common features in an amine and an acid group. A quick quiz round introduces the R group and time is taken to explain how the structure of this side chain is the only structural difference. Students will be introduced to the existence of hydrophobic and hydrophilic R groups so that they are able to apply this knowledge in future lessons where structure and shape is considered. Some time is also given to look at cysteine in greater detail due to the presence of sulfur atoms and once again a link is made to disulfide bridges for upcoming lessons. Another quiz round called LINK TO THE FUTURE will allow the students to recognise the roles performed by amino acids in the later part of the course such as translation and in the formation of dipeptides. The lesson concludes with a task that describes the breakage of the peptide bonds during hydrolysis reactions.

This fully-resourced lesson describes the key steps in the process of DNA replication, including the role of DNA polymerase. Both the detailed PowerPoint and accompanying resources have been designed to cover point 2.11 (i) of the Pearson Edexcel A-level Biology A specification and this lesson also explains why this replication is known as semi-conservative in order to prepare the students for the following lesson on Meselson and Stahl’s experiment. The main focus of this lesson is the role of DNA polymerase in the formation of the growing nucleotide strands but the students will also learn that the hydrogen bonds between nucleotide bases are broken by DNA helicase and that DNA ligase joins 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.

Adenosine triphosphate is the universal energy currency and this lesson focuses on the role of this molecule in cell. The PowerPoint has been designed to cover point1.2 © of the CIE International A-level Biology specification and also explains how ATP must be hydrolysed to release energy and then re-synthesised during respiration and photosynthesis in the mitochondria and chloroplast respectively. As students were introduced to the structure of DNA and RNA at GCSE, the start of this lesson challenges them on their knowledge of these polynucleotides so that they can recognise that ATP 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 within cells and the examples of active transport and skeletal muscle contraction are used as these are covered in greater detail in topics 4 and 15. The final part of the lesson considers how ATP must be re-synthesised and students will learn that this occurs in the mitochondria and chloroplast during aerobic respiration and photosynthesis respectively.

This lesson focuses on the nature of the genetic code and specifically focuses on the degenerate nature to make a link to gene mutations which is covered later in topic 2. The PowerPoint has been designed to cover point 2.7 of the Pearson Edexcel A-level Biology (Salters Nuffield) specification which states that students should understand how the descriptive terms triplet code, degenerate and non-overlapping relate to the genetic code. The lesson begins by introducing the terms near universal and non-overlapping in addition to degenerate. A quick quiz competition is used to generate the number 20 so that the students can learn that there are 20 proteinogenic amino acids in the genetic code. This leads into a challenge, where they have to use their prior knowledge of DNA to calculate the number of different DNA triplets (64) and the mismatch in number is then discussed and related back to the lesson topic. Moving forwards, substitutions and deletions are briefly introduced so that they can see how although one substitution can change the primary structure, another will change the codon but not the encoded amino acid. The lesson concludes with a brief look at the non-overlapping nature of the code so that the impact of a base deletion can be understood when covered in greater detail with cystic fibrosis