This fully-resourced lesson describes the process of DNA replication and explains how this ensures genetic continuity between generations. Both the detailed PowerPoint and accompanying resources have been designed to cover point 1.5.2 of the AQA A-level Biology specification and also explains why it is known as semi-conservative. The main focus of this lesson is the roles of DNA helicase in the breaking the hydrogen bonds between nucleotide bases and DNA polymerase in forming the growing nucleotide strands. Students are also introduced to DNA ligase to enable them to understand how this enzyme functions to join 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 engaging lesson acts as an introduction to carbohydrates and describes the differences between monosaccharides, disaccharides and polysaccharides. The PowerPoint and accompanying worksheet have been designed to cover the first part of points 1.12 & 1.13 of the Pearson Edexcel A-level Biology A specification and make clear links to the upcoming lessons in this sub-topic on these three main groups of carbohydrates. 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. A number of quick quiz rounds have been written into the lesson to introduce key terms in a fun and memorable way and the first round allows the students to meet some of common monosaccharides. Moving forwards, students will learn that a disaccharide is formed when two of these monomers are joined together and they are then challenged on their knowledge of condensation reactions which were originally encountered during the lesson on water. Students will understand how multiple reactions and multiple glycosidic bonds will result in the formation of a polysaccharide and glycogen and starch are introduced as well as amylose and amylopectin as components of this latter polymer. The final part of the lesson considers how hydrolysis reactions allow polysaccharides and disaccharides to be broken back down into monosaccharides.

Amino acids are the monomers of polypeptides and this lesson describes their structure and makes links to related topics such as genes and dipeptides. The engaging PowerPoint has been designed to cover the first part of point 1.4.1 of the AQA A-level Biology specification 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, 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 mineral ions.

This detailed and engaging lesson describes the basic structure of a mononucleotide and the similarities and differences between DNA and RNA. The PowerPoint and accompanying worksheet containing exam-style questions have been designed to cover points 2.5 (i) & (ii) of the Pearson Edexcel A-level Biology A specification. In topic 1, the students were introduced to a number of monomers and the start of the lesson challenges them to recognise the key term nucleotide when only the letters U, C and T are shown. The next part of the lesson describes the structure of a DNA nucleotide and an RNA nucleotide so that the pentose sugar and the bases adenine, cytosine and guanine can be recognised as similarities whilst deoxyribose and ribose and thymine and uracil are seen as the differences. Time is taken to discuss how a phosphodiester bond is formed between adjacent nucleotides and their prior knowledge and understanding of condensation reactions is tested through a series of questions. Students are then introduced to the purine and pyrimidine bases and this leads into the description of the double-helical structure of DNA and the hydrogen bonds between complementary bases. The final section of the lesson describes the structure of mRNA, tRNA and rRNA and students are challenged to explain why this single stranded polynucleotide is shorter than DNA In addition to the current understanding and prior knowledge checks, a number of quiz rounds have been written into the lesson to introduce key terms in a fun and memorable way and the final round acts as a final check on the structures of DNA and RNA.

This engaging lesson describes the relationship between the structure, properties and functions of a phopholipid and cholesterol. The PowerPoint has been written as the second 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 there is a particular focus on their roles in membranes to link to module 2.1.5. In the previous lesson, the students met triglycerides and a quick quiz round called FAMILY AFFAIR is used at the start of the lesson to challenge the students on their knowledge of the structure of this macromolecule 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 module 2.1.5 on the fluid mosaic model. Students are briefly introduced to facilitated diffusion and reminded of active transport so they can recognise that proteins will be found in the membrane to allow for movement of large or polar molecules. The remainder of the lesson focuses on cholesterol, beginning with the structure. The hydrophobic nature of this molecule is then considered and discussed so that they can understand its role in the regulation of membrane fluidity. That just leaves one final quiz round which identifies vitamin D, testosterone and oestrogen as three substances that are formed from cholesterol

This fully-resourced lesson describes the relationship between the structure and function of globular proteins, specifically focusing on haemoglobin, insulin and pepsin. The detailed and engaging PowerPoint and accompanying resources have been primarily designed to cover specification point 2.1.2 (n) of the OCR A-level Biology A course but due to the detailed coverage of haemoglobin, the start of this lesson could also be used when teaching lessons that cover specification points 3.1.2 (i) and (j). By the end of the lesson, students will be able to describe that the interactions of the hydrophobic and hydrophilic R groups results in a spherical shape that is soluble in water and be able to explain the importance of this property with reference to the individual functions of these three globular proteins. They will also be able to name key individual details for each protein, such as haemoglobin being a conjugated protein, insulin being linked by numerous disulfide bridges and pepsin’s low number of basic R groups meaning it is stable in the acidic environment of the stomach. Extra time has gone into the planning of this lesson to ensure that links are continuously made to previous topics such as amino acids and the levels of protein structure as well as to upcoming topics like the control of blood glucose concentration that is covered in module 5.1.4.

This detailed lesson describes the different levels of protein structure and focuses on the bonds that hold these molecules in shape. Both the engaging PowerPoint and accompanying resources have been designed to cover specification point 2.3 (b) of the CIE International A-level Biology course and makes continual links to previous lessons such as amino acids & peptide bonds as well as to upcoming lessons like enzymes and antibodies. 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 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 detailed lesson describes how the structure of a prokaryotic cell differs from the structure of an eukaryotic cell. The engaging PowerPoint and accompanying resources have been designed to cover the first part of point 2.1.2 of the AQA A-level Biology specification and describes how the size and cell structures differ and also covers the additional features that are found in some prokaryotic cells. A clear understanding of terminology is important for A-level Biology so this lesson begins with a challenge, where the students have to add an additional prefix to their prefix and suffix table which they believe will translate as before or in front of. This leads into the discovery of the meaning of prokaryote as before nucleus and this 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.

This fully-resourced lesson describes how the eukaryotic cells of complex multicellular organisms become specialised for specific functions. The detailed and engaging PowerPoint and accompanying resources have been designed to cover the 3rd part of point 2.1.1 of the AQA A-level Biology specification and also describes how these specialised cells are organised into tissues, organs and organ systems. The start of the lesson focuses on the difference in the SA/V ratio of an amoeba and a human in order to begin to explain why the process of differentiation is critical 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 remainder of the lesson focuses on specialised plant cells and the differing shapes and features of the palisade and spongy mesophyll cells and the guard cells are covered at length and in detail. Step by step guides will support the students so that they can recognise the importance of the structures and links are made to upcoming topics such as diffusion, active transport and osmosis so that students are prepared for these when covered in the future. This lesson has been written to continually tie in with the previous two lessons in this specification point which are uploaded under the titles of the structure of eukaryotic animal and plant cells.

This lesson describes the mechanism of ventilation in mammals, including the roles of the ribcage, intercostal muscles and the diaphragm. The content of the engaging PowerPoint has been designed to cover specification point 3.1.3 (d) of the OCR A-level Biology A specification and describes the mechanism of inhalation and exhalation at rest. The lesson begins with a focus on the diaphragm and students will discover that this sheet of muscle is found on the floor of the thoracic cavity. Whilst planning the lesson, it was deemed important to introduce this region of the body at an early stage because the best descriptions will regularly reference the changes seen in this cavity. 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 the air takes on moving into the lungs. The remainder of the lesson involves a task which challenges the students to describe exhalation and then the accessory muscles involved in forced ventilation are also considered.

This engaging lesson describes how the structure and properties of phospholipids relate to their functions in cell membranes. The PowerPoint has been designed to cover point 1.2 (iv) as detailed in the Edexcel A-level Biology B specification and includes regular references to the previous lesson on triglycerides to check on knowledge and understanding 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 lessons in topic 4 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 4 lessons.

This clear and detailed lesson describes how ATP is formed by chemiosmosis during the process of oxidative phosphorylation. The PowerPoint has been designed to cover all of the specification points under point 5.4 of the Edexcel A-level Biology B specification and includes details of the electron transport chain, proton gradients and ATP synthase including the roles of the electron carriers, the mitochondrial membranes and oxygen. The lesson begins with a discussion about the starting point of the reaction. In the previous stages, the starting molecule was the final product of the last stage but in this stage, it is the reduced coenzymes which release their hydrogen atoms. Moving forwards, the process of oxidative phosphorylation is covered in 7 detailed steps and at each point, key facts are discussed and explored in further detail to enable a deep understanding to be developed. Students will see how the proton gradient across the inner membrane is created and that the flow of protons down the channel associated with ATP synthase results in a conformational change and the addition of phosphate groups to ADP by oxidative phosphorylation. Understanding checks are included throughout the lesson to enable the students to assess their progress and prior knowledge checks allow them to recognise the clear links to other topics and modules. This lesson has been written to tie in with the other uploaded lessons on the previous stages of aerobic respiration - glycolysis, the Link reaction and the Krebs cycle.

This fully-resourced lesson describes how light intensity, carbon dioxide concentration and temperature limit the rate of photosynthesis. The PowerPoint and accompanying resources have been designed to cover point 5.2.1 (g) (i) of the OCR A-level Biology A specification and also includes a brief consideration of water stress. The lesson has been specifically written to tie in with the three previous lessons in this module which covered the structure of the chloroplast, the light-dependent and light-independent stages and the uses of TP. Exam-style questions are included throughout the lesson and these require the students to explain why light intensity is important for both reactions as well as challenging them on their ability to describe how the relative concentrations of GP, TP and RuBP would change as carbon dioxide concentration decreases. There are also links to previous topics such as enzymes when they are asked to explain why an increase in temperature above the optimum will limit the rate of photosynthesis. Step by step guides are included to support them to form some of the answers and mark schemes are always displayed so that they can quickly assess their understanding and address any misconceptions.

This fully-resourced lesson describes the series of reactions in the light- independent stage of photosynthesis. The detailed PowerPoint and accompanying resources have been designed to cover the details of point 5.2.1 (e) of the OCR A-level Biology A specification and detailed planning includes continual links to the previous lesson on the light-dependent stage to ensure that students recognise 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 light-independent stage. 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 consider 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 engaging lesson describes the basic structure of an amino acid and introduces them as the monomers of polypeptides. The PowerPoint has been designed to cover point 2.6 (i) of the Edexcel International A-level Biology 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 covered later in the topic. Moving forwards, the students are given 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 the inheritance of genes with loci on the X chromosomes and considers biological examples. The detailed PowerPoint and accompanying resources have been designed to cover point 2.15 (ii) of the Edexcel International A-level specification and focuses on the inheritance of red-green colour blindness and haemophilia in humans Key genetic terminology is used throughout and the lesson begins with a check on their ability to identify the definition of homologous chromosomes. Students will recall that the sex chromosomes are not fully homologous and that the smaller Y chromosome lacks some of the genes that are found on the X. This leads into one of the numerous discussion points, where students are encouraged to consider whether females or males are more likely to suffer from sex-linked diseases. In terms of humans, the lesson focuses on haemophilia and red-green colour blindness and a step-by-step guide is used to demonstrate how these specific genetic diagrams should be constructed and how the phenotypes should then be interpreted. The final task of the lesson challenge the students to apply their knowledge to an exam question about chickens and how the rate of feather production in chicks can be used to determine gender. All of the tasks are differentiated so that students of differing abilities can access the work and all exam questions have fully-explained, visual mark schemes to allow them to assess their progress and address any misconceptions