A Science teacher by trade, I've also been known to be found teaching Maths and PE! However, strange as it may seem, my real love is designing resources that can be used by other teachers to maximise the experience of the students. I am constantly thinking of new ways to engage a student with a topic and try to implement that in the design of the lessons.
A Science teacher by trade, I've also been known to be found teaching Maths and PE! However, strange as it may seem, my real love is designing resources that can be used by other teachers to maximise the experience of the students. I am constantly thinking of new ways to engage a student with a topic and try to implement that in the design of the lessons.
This engaging lesson describes how the structure of the phloem enables this vascular tissue to transport organic substances in plants. Both the detailed PowerPoint and accompanying resource have been designed to cover the 3rd part of point 3.4.2 (Mass transport in plants) of the AQA A-level Biology specification.
Comparative questions between the xylem and phloem are very common so the lesson begins by challenging the students to use their prior knowledge to complete the xylem column of a table with details including the presence of lignin and bordered pits and specific substances which are transported in this tissue. This has been written into the lesson to encourage the students to start to think about how the structure and function of the phloem may compare. 3 quiz rounds have been included in the lesson to maintain motivation and to introduce key terms. The first of these rounds will challenge the students to be the first to recognise descriptions of sucrose and amino acids as they learn that these are the two most common assimilate, which are the substances transported by the phloem. The focus of this lesson is the relationship between structure and function and all descriptions have these two parts highlighted to support the students to recognise the link. Moving forwards, students will be introduced to the sieve tube elements and the companion cells and time is taken to consider why the structure of these cells are so different. Current understanding checks are interspersed throughout the lesson to ensure that any misconceptions can be quickly addressed. The plasmodesmata is described to allow students to understand how assimilates move from the companion cells to the sieve tube elements as this will be particularly important for the next lesson on translocation. The final task of the lesson challenges the students to write a detailed passage about the structure and function of the phloem, incorporating all of the information that they have absorbed throughout the course of the lesson.
This detailed lesson describes the transport of water into the plant as well as the movement across the cortex to the endodermis and to the xylem. Both the engaging PowerPoint and accompanying resource have been designed to cover the first part of point 3.1.3 (d) as detailed in the OCR A-level Biology A specification.
The lesson begins by looking at the specialised features of the root hair cell so that students can 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 symplast, vacuolar and apoplast pathways that water and minerals use to transverse 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 apoplast pathway is needed for the water carrying the ions. The main part of the lesson focuses on the role of the endodermis in the transport of the water and ions into the xylem. Students will be introduced to the Casparian strip and will learn how this layer of cells blocks the apoplast 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 lesson has been specifically written to tie in with the next lesson on the pathways and mechanisms by which water and mineral ions are transported to the leaves and then out into the air surrounding the leaves.
This fully-resourced lesson describes how the mechanisms of root pressure and transpiration pull move water upwards in the xylem to the leaves. The detailed PowerPoint and accompanying, differentiated resources have primarily been designed to cover the second part of point 7.2 [c] of the CIE International A-level Biology specification but also cover 7.2 [b] as the cohesion-tension theory and adhesion are described and explained.
This lesson has been written to follow on from the end of the previous lesson, which finished with the description of the transport of the water and mineral ions from the endodermis to the xylem. Students are immediately challenged to use this knowledge to understand root pressure and the movement by mass flow down the pressure gradient. Moving forwards, time is taken to study the details of transpiration pull and the interaction between cohesion, tension and adhesion in capillary action is explained. Understanding is constantly checked through a range of tasks and prior knowledge checks are also written into the lesson to challenge the students to make links to previously covered topics such as the structure of the transport tissues. The final part of the lesson considers the journey of water through the leaf and ultimately out of the stomata in transpiration. A step by step guide using questions to discuss and answer as a class is used to support the students before the final task challenges them to summarise this movement through the leaf.
All 3 of the lessons that are included in this bundle are detailed and fully-resourced with differentiated worksheets to cover the content of topic 3.4.2 (Mass transport in plants) as set out in the AQA A-level Biology specification.
Some students do not fully engage with this topic and therefore time has been taken to design each lesson so that it maintains motivation through a wide range of tasks. These tasks include quiz competitions which introduce key terms in a memorable way.
The specification points that are covered in these three lessons are:
Xylem as the tissue that transports water in the stem and leaves of a plant
The cohesion-tension theory of water transport in the xylem
Phloem as the tissue that transports organic substances in plants
The mass flow hypothesis for the mechanism of translocation in plants
If you would like to see the quality of these lessons, download the translocation lesson as this has been shared for free.
This fully-resourced lesson describes how the structure of the xylem tissue allows water to be transported in the stem and leaves. Written for AQA A-level Biology, the engaging and detailed PowerPoint and the accompanying worksheets cover the 1st part of specification point 3.4.2 (mass transport in plants) and includes a detailed description of the cohesion-tension theory.
The first part of the lesson focuses on the relationship between the structure and function of the xylem tissue. A number of quiz competitions have been included in the lesson to maintain engagement and to introduce key terms. The 1st round does just that and results in the introduction of lignin which leads into the explanation of how the impregnation of this substance in the cell walls result in the death and subsequent decay of the cell structures. Students are encouraged to discuss how the formation of this hollow tube enables the transport of water to be effective. Moving forwards, other structures such as the bordered pits are introduced and an understanding of their function is tested later in the lesson. The remainder of the lesson focuses on the transport of water in the stem and leaves by root pressure and the transpiration pull, which includes cohesion, tension and adhesion. The lesson has been designed to make links to information covered earlier in the lesson as well to topics from earlier in the specification such as cell structures and biological molecules
Due to the extensiveness of this lesson, it is estimated that it will take in excess of 2/3 A-level teaching hours to cover the detail included in this lesson.
This detailed lesson describes the structure of a nucleotide including the structure of the phosphorylated nucleotide, ATP. The engaging PowerPoint has been designed to cover point (a) of topic 6.1 as detailed in the CIE International A-level Biology specification and links are made throughout to earlier topics such as biological molecules as well as to upcoming topics like DNA structure and replication.
Students were introduced to the term monomer and nucleotide in topic 2, so the start of the lesson challenges them to recognise this latter term when only the letters U, C and T are shown. This has been designed to initiate conversations about why only these letters were used so that the nitrogenous bases can be discussed later in greater detail. Moving forwards, students will learn that a nucleotide is the monomer to a polynucleotide and that deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are two examples of this type of polymer. The main part of the lesson has been filled with various tasks that explore the structural similarities and structural differences between DNA and RNA. This begins by describing the structure of a nucleotide as a phosphate group, a pentose sugar and a nitrogenous base. Time is taken to consider the details of each of these three components which includes the role of the phosphate group in the formation of a phosphodiester bond between adjacent nucleotides on the strand. At this point students are challenged on their understanding of condensation reactions and have to identify how the hydroxyl group associated with carbon 3 is involved along with the hydroxyl group of the phosphoric acid molecule. A number of quiz rounds are used during this lesson, as a way to introduce key terms in a fun and memorable way. One of these rounds introduces adenine and guanine as the purine bases and thymine, cytosine and uracil as the pyrimidine bases and the students are shown that their differing ring structures can be used to distinguish between them. The remainder of the lesson focuses on ATP as a phosphorylated nucleotide and links are made to the hydrolysis of this molecule for energy driven reactions in cells such as active transport
Monosaccharides are the monomers from which larger carbohydrates are formed and this lesson describes their structure and roles in living organisms. The detailed and engaging PowerPoint and accompanying resources have been designed to cover the first part of point 1.2 of the AQA A-level Biology specification and looks at alpha-glucose, beta-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 and students are again challenged to draw a molecule of glucose, this time for the beta form. The remainder of the lesson focuses on the roles of the 6 monosaccharides and the final task involves a series of application questions where the students are challenged to suggest why ribose could be considered important for active transport and muscle contraction
This fully-resourced lesson describes the sliding filament model of muscular contraction and has been designed to cover the 4th part of point E2 in UNIT 2 of the Pearson BTEC Level 3 National Diploma in Sport and Exercise Science specification. The wide range of activities included in the lesson will engage and motivate the students whilst the understanding checks will allow them to assess their progress.
The lesson begins by getting them to reveal the prefix myo so that they can recognise that myology is the study of muscles. This leads into the next task, where they have to identify two further terms beginning with myo and are the names of structures involved in the arrangement of skeletal muscle. Key terminology is used throughout the lesson so that students feel comfortable when they encounter this in questions. Students were introduced to the sarcomere and the bands and zones that are found within a myofibril in a previous lesson and they are challenged to discuss how the sarcomere can narrow but the lengths of the myofilaments remain the same. The main task of the lesson involves the formation of a bullet point description of the sliding filament model where one event is the trigger for the next. Time is taken during this section to focus on the involvement of calcium ions and ATP. The final part of the lesson involves students having to apply their knowledge by describing the effect on muscle contraction when a part of a structure is unable to function correctly.
This fully-resourced lesson looks at the detailed structure of a muscle fibre, and focuses on the proteins, bands and zones that are found in the myofibril. The engaging PowerPoint and acccompanying resource have been designed to cover the third part of point E2 in UNIT 2 of the Pearson BTEC Level 3 National Diploma in Sport and Exercise Science specification.
The lesson begins with an imaginary question from the quiz show POINTLESS, where students have to recognise a range of fields of study. This will reveal myology as the study of muscles so that key terms like myofibril and myosin can be introduced. Moving forwards, students will be shown the striated appearance of this muscle so they can recognise that some areas appear dark where both myofilaments are found and others as light as they only contain actin or myosin. A quiz competition is used to introduce the A band, I band and H zone and students then have to use the information given to label a diagram of the myofibril. The final task challenges the students to use their knowledge of the sliding filament theory to recognise which of these bands or zones narrow or stay the same length when muscle is contracted.
The biological molecules topic is incredibly important, not just because it is found at the start of the course, but also because of its detailed content which must be well understood to promote success with the other 7 AQA A-level Biology topics. Many hours of intricate planning has gone into the design of all of the 20 lessons that are included in this bundle to ensure that the content is covered in detail, understanding is constantly checked and misconceptions addressed and that engagement is high. This is achieved through the wide variety of tasks in the PowerPoints and accompanying worksheets which include exam-style questions with clear answers, discussion points, differentiated tasks and quick quiz competitions.
The following specification points are covered by the lessons within this bundle:
Monomers and polymers
Condensation and hydrolysis reactions
Common monosaccharides
Maltose, sucrose and lactose
The structure and functions of glycogen, starch and cellulose
Biochemical tests using Benedict’s solution for reducing sugars and non-reducing sugars and iodine/potassium iodide for starch
The structure and properties of triglycerides and phospholipids
The emulsion test for lipids
The structure of amino acids
The formation of dipeptides and polypeptides
The levels of protein structure
The biuret test for proteins
Enzymes act as biological catalysts
The induced-fit model of enzyme action
The properties of an enzyme
The effect of temperature on the rate of an enzyme-controlled reaction
The effect of enzyme and substrate concentration on the rate of an enzyme-controlled reaction
The effect of competitive and non-competitive inhibitors on the rate of an enzyme-controlled reaction
The structure of DNA and RNA
The semi-conservative replication of DNA
ATP as the universal energy currency
The properties of water and its importance in Biology
Inorganic ions
Due to the detail of each of these lessons, it is estimated that it will take in excess of 2 months of allocated teaching time to cover the content.
If you would like to see the quality of the lessons, download the monomers and polymers, polysaccharides, triglycerides, dipeptides and polypeptides and inorganic ions lessons as these have been shared for free
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 concise lesson describes the basic structure of an amino acid and introduces them as the monomers of polypeptides. The engaging PowerPoint has been designed to cover point 2.9 (i) of the Pearson Edexcel A-level Biology A specification and has been specifically written to lead into the next lesson on 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 as detailed in specification point 2.8. Moving forwards, the 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, before cysteine is considered in greater detail due to the presence of sulfur atoms. Students are briefly introduced to disulfide bridges so they will recognise how particular bonds form between the R groups in the tertiary structure which is covered in the next lesson. The lesson concludes with one more quiz round called LINK TO THE FUTURE where the students will see the roles played by amino acids in the later part of the course such as translation and dipeptides.
This fully-resourced lesson describes how the different properties of water make this biological molecule incredibly important in Biology. The engaging PowerPoint and accompanying worksheets have been designed to cover point 1.7 of the AQA A-level Biology specification.
Hydrolysis reactions have been a recurring theme throughout topic 1, 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. A quick quiz round is used to introduce cohesion and tension so students can understand how the column of water is able to move along this vascular tissue without interruption. 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 fully-resourced lesson describes how triglycerides are formed during condensation reactions and compares saturated and unsaturated lipids. The engaging PowerPoint and accompanying worksheets have been designed to cover the points 1.14 (i) & (ii) of the Pearson Edexcel A-level Biology A 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 topics 1.12 & 1.13 so that the structure of a triglyceride can be introduced. Students will learn that this macromolecule is formed from one glycerol molecule and three fatty acids and have to use their understanding of condensation reactions to draw the final structure. Time is taken to look at the difference in structure and properties of saturated and unsaturated fatty acids and students will be able to identify one from the other when presented with a molecular formula. The final part of the lesson explores how the various properties of a triglyceride mean that it has numerous roles in organisms including that of an energy store and source and as an insulator of heat and electricity.
This detailed 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 and fully-resourced lesson describes the relationship between the structure, properties and functions of glycogen, starch and cellulose. The engaging PowerPoint and accompanying resources have been designed to cover specification points 2.1.2 (f) & (g) of the OCR A-level Biology A course and continual 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, properties and functions of these large carbohydrates 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 dictate whether the chain spirals or not. Following the description of the structure of glycogen, students are challenged to design an exam question in the form of a comparison table so that it can be completed as the lesson progresses and they learn more about starch and cellulose. This includes a split in the starch section of the table so that the differing structures and properties of amylose and amylopectin can be considered. 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. In the final part of the lesson, time is taken to focus on the hydrogen bonds between rotated glucose molecules on the same chain and between different chains and to explain how the formation of cellulose microfibrils and macrofibrils provides plant cells with the additional strength needed to support the whole plant.
Due to the detail included in this lesson, it is estimated that it will take in excess of 2 hours of allocated teaching time to complete
This fully-resourced lesson describes the relationship between the structure, properties and functions of triglycerides in living organisms. The engaging PowerPoint and accompanying worksheets have been designed to be the first lesson in a series of two that cover specification points 2.1.2 (h), (i) & (j) of the OCR A-level Biology A course and the lesson contains numerous references to relevant 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 the sub-module so that the structure of a triglyceride can be introduced. Students will learn that this macromolecule is formed from one glycerol molecule and three fatty acids and have to use their understanding of condensation reactions to draw the final structure. Time is taken to look at the difference in structure and properties of saturated and unsaturated fatty acids and students will be able to identify one from the other when presented with a molecular formula. The final part of the lesson explores how the various properties of a triglyceride mean that it has numerous roles in organisms including that of an energy store and source and as an insulator of heat and electricity.
This lesson describes how disaccharides like maltose, sucrose and lactose are formed from the condensation of two monosaccharides and can also be broken down by hydrolysis reactions. The PowerPoint and accompanying question sheet have been designed to cover specification point 2.1.2 (e) of the OCR A-level Biology A specification but also makes repeated 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 extracellular enzymes, translocation in the phloem and the Lac Operon in cellular control. The lesson finishes with two exam-style questions where students have to demonstrate and apply their newly acquired knowledge when presented with unfamiliar disaccharides
Some of the key biological topics are covered in topic 2 of the Pearson Edexcel A-level Biology A (Salters Nuffield) course and include the transport of materials across cell membranes, DNA structure and replication, protein synthesis and monohybrid inheritance. In line with this, many hours of intricate planning have gone into the design of all of the 19 lessons that are included in this bundle to ensure that the content is covered in detail, understanding is constantly checked to immediately address misconceptions and that engagement is high. This is achieved through the wide variety of tasks in the PowerPoints and accompanying worksheets which include exam-style questions with clear answers, discussion points, differentiated tasks and quick quiz competitions.
The following specification points are covered by the lessons within this bundle:
The properties of gas exchange surfaces in living organisms
Understand how the rate of diffusion is dependent on these properties and can be used in the calculation of the rate of diffusion by Fick’s law
Adaptations of the mammalian lung for rapid gaseous exchange
Structure and properties of cell membranes
Simple and facilitated diffusion as methods of passive transport
The involvement of ATP and carrier proteins in active transport, endocytosis and exocytosis
The basic structure of mononucleotides
The structures of DNA and RNA
The process of protein synthesis
The roles of the template strand, mRNA and tRNA
The nature of the genetic code
A gene is a sequence of bases on DNA that codes for the amino acid sequence of a polypeptide
The basic structure of an amino acid
The formation of polypeptides and proteins
The primary, secondary, tertiary and quaternary structure of proteins
Globular and fibrous proteins using haemoglobin and collagen as examples
The mechanism of action and the specificity of enzymes
Enzymes are biological catalysts that reduce activation energy
The process of DNA replication
Errors in DNA replication can give rise to mutations
The meaning of key genetic terms
Patterns of inheritance, in the context of monohybrid inheritance
Understand how the expression of a gene mutation in people with cystic fibrosis impairs the functioning of the gaseous exchange, digestive and reproductive systems
Understand the uses and implications of genetic screening and prenatal testing
Due to the detail included in each of these lessons, it is estimated that it will take in excess of 2 months of allocated teaching time to cover the content.
If you would like to see the quality of the lessons, download the gas exchange surfaces, cell membranes, transcription, globular and fibrous proteins, monohybrid inheritance and cystic fibrosis lessons as these have been shared for free
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.