This lesson describes the tests that detect reducing and non-reducing sugars and starch using Benedict’s solution and iodine/potassium iodide. The PowerPoint and accompanying resource are part of the last lesson in a series of 4 lessons which have been designed to cover the content of topic 1.2 (Carbohydrates) of the AQA A-level Biology specification. The lesson begins with an explanation of the difference between a qualitative and quantitative test so that the students recognise that the two tests described within this lesson indicate the presence of a substance but not how much. The students are likely to have met these tests at GCSE so this lesson has been planned to build on that knowledge and to add the knowledge needed at this level. A step by step guide walks the students through each stage of the tests for reducing and non-reducing sugars and application of knowledge questions and prior knowledge checks are included at appropriate points to ensure understanding is complete. Time is also taken to ensure that students understand the Science behind the results. The rest of the lesson focuses on the iodine test for starch and the students will learn that the colour change is the result of the movement of an ion into the amylose helix.

This lesson describes the methods used to test for reducing and non-reducing sugars and starch using Benedict’s solution and iodine/potassium iodide. The PowerPoint and accompanying resource are part of the first lesson in a series of 2 which have been designed to cover the content of point 2.1 (a) of the CIE A-level Biology specification. The lesson begins with an explanation of the difference between a qualitative and quantitative test to allow the students to understand that the two tests described within this lesson indicate the presence of a substance but not how much. The students are likely to have met these tests during their studies at a lower level so this lesson has been planned to build on that knowledge and to add the knowledge needed at this level. A step by step guide walks the students through each stage of the tests for reducing and non-reducing sugars and application of knowledge questions are included at appropriate points to ensure that understanding is complete. Time is also taken to ensure that students understand the Science behind the results. The rest of the lesson focuses on the iodine test for starch and the students will learn that the colour change is the result of the movement of an ion into the amylose helix. As this is the first lesson in topic 2 (Biological molecules), students are yet to learn about the structure and function of the carbohydrates which these tests detect. Therefore, included in the PowerPoint are numerous “LINK TO THE FUTURE” slides, where important details about the structure and function of the monosaccharides, disaccharides and polysaccharides are introduced.

This lesson describes the chemical tests for proteins, reducing and non-reducing sugars, starch and lipids and explains how to interpret the results. The PowerPoint and accompanying resource have been designed to cover point 2.1.2 (q) of the OCR A-level Biology A specification. The lesson begins with an explanation of the difference between a qualitative and quantitative test so that the students recognise that the four tests described within this lesson indicate the presence of a substance but not how much. The students are likely to have met these tests at GCSE so this lesson has been planned to build on that knowledge and to add the knowledge needed at this level. A step by step guide walks the students through each stage of the tests for reducing and non-reducing sugars and application of knowledge questions and prior knowledge checks are included at appropriate points to ensure understanding is complete. Time is also taken to ensure that students understand the Science behind the results. The next part of the lesson focuses on the iodine test for starch and the students will learn that the colour change is the result of the movement of an ion into the amylose helix. The rest of the lesson describes the steps in the biuret test for proteins and the emulsion test for lipids. The students will learn that the addition of sodium hydroxide and then copper sulphate will result in a colour change from light blue to lilac if a protein is present and that following the addition of a sample to ethanol and then water, a cloudy emulsion is observed if a lipid is present.

This lesson describes the extracellular action of peptide hormones and the role played by steroid hormones in binding to DNA transcription factors. The detailed PowerPoint and accompanying resources have been designed to cover point 7.22 of the Edexcel International A-level Biology specification and focuses on the differing effects of these two types of hormones on their target cells Students should have a base knowledge of the endocrine system from GCSE so this lesson has been planned to build on that knowledge and to add the detail needed at this level. The lesson begins by challenging this knowledge to check that they understand that endocrine glands secrete these hormones directly into the blood. Students will learn that most of the secreted hormones are peptide (or protein) hormones and a series of exam-style questions are used to challenge them on their recall of the structure of insulin as well as to apply their knowledge to questions about glucagon. Moving forwards, the students are reminded that hormones have target cells that have specific receptor sites on their membrane. The relationship between a peptide hormone as a first messenger and a second messenger on the inside of the cell is covered in detail in an upcoming lesson but students are briefly introduced to G proteins and cyclic AMP so they are prepared. The rest of the lesson focuses on steroid hormones and specifically their ability to pass through the membrane of a cell and to bind to transcription factors, as exemplified by oestrogen. Students covered transcription and the control of gene expression in topics 2 and 3 so the final tasks challenge their recall of these concepts

This fully-resourced lesson describes the relationship between the properties and functions of the fibrous proteins, collagen, keratin and elastin. The detailed PowerPoint and accompanying resources have been designed to cover point 2.1.2 (o) of the OCR A-level Biology A specification but also make links to upcoming topics such as blood vessel structure and the immune system as well as constantly challenging students on their knowledge of proteins from earlier in this module. The lesson begins by challenging the students to recognise 7 structures found in animals from their descriptions and once they’ve written feathers, cartilage, bones, arteries, tendons, callus and skin into the right places, they will reveal the term fibrous and learn that these types of protein are found in these structures. Using their knowledge of the properties of globular proteins, they will learn that the insolubility of fibrous proteins allows them to form fibres, which perform structural functions. The rest of the lesson focuses on the functions of collagen, keratin and elastin and time is taken to discuss the key details and to make links to future topics so that students can recognise the importance of cross-modular based answers. A series of exam-style questions are used to challenge their knowledge of protein structure as well as their ability to apply their knowledge to an unfamiliar situation when learning that elastin is found in the walls of the urinary bladder. All of the questions have mark schemes embedded into the PowerPoint to allow them to immediately assess their understanding. This lesson has been specifically planned to tie in with the previous lesson on globular proteins as well as the one preceding that on the structures of proteins

This lesson explains how negative feedback control maintains systems within narrow limits and uses biological examples to describe the meaning of positive feedback. The PowerPoint and accompanying resources have been designed to cover points 7.11 (i) and (ii) of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification but have been planned to provide important details for upcoming topics such as the importance of homeostasis during exercise and the depolarisation of a neurone. The normal ranges for blood glucose concentration, blood pH and body temperature are introduced at the start of the lesson to allow students to recognise that these aspects have to be maintained within narrow limits. A series of exam-style questions then challenge their recall of knowledge from topics 1 - 6 as well as earlier in topic 7 to explain why it’s important that each of these aspects is maintained within these limits. The students were introduced to homeostasis at GCSE, so this process is revisited and discussed, so that students are prepared for an upcoming lesson on exercise, as well as for the next part of the lesson on negative feedback control. Students will learn how this form of control reverses the original change and biological examples are used to emphasise the importance of this system for restoring levels to the limits (and the optimum). The remainder of the lesson explains how positive feedback differs from negative feedback as it increases the original change and the role of oxytocin in birth and the movement of sodium ions into a neurone are used to exemplify the action of this control system.

This lesson describes the classification system, focusing on the biological classification of a species and the 7 taxa found above this lowest taxon. The engaging PowerPoint and accompanying resource have been designed to cover point 4.6 (i) of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification and also describes the binomial naming system which uses the genus and species. The lesson also contains links to upcoming lessons where molecular phylogeny is described and the three-domain system is covered in greater detail with a focus on the results of Carl Woese’s rRNA study The lesson begins by looking at the meaning of a population in Biology so that the term species can be introduced. A hinny, which is the hybrid offspring of a horse and a donkey, is used to explain how these two organisms must be members of different species because they are unable to produce fertile offspring. Moving forwards, students will learn that classification is a means of organising the variety of life based on relationships between organisms using differences and similarities in phenotypes and in genotypes and is built around the species concept and that in the modern-day classification hierarchy, species is the lowest taxon. A quiz runs throughout the lesson and this particular round will engage the students whilst they learn (or recall) the names of the other 7 taxa and the horse and the donkey from the earlier example are used to complete the hierarchy. Students will understand that the binomial naming system was introduced by Carl Linnaeus to provide a universal name for each species and they will be challenged to apply their knowledge by completing a hierarchy for a modern-day human, by spotting the correct name for an unfamiliar organism and finally by suggesting advantages of this system.

This lesson describes classification as a means of organising the variety of life based on relationships between organisms. The engaging PowerPoint and accompanying resource have been designed to cover point 4.14 (i) of the Edexcel International A-level Biology specification and focuses on the classification hierarchy where species is the lowest taxon but also describes the binomial naming system which uses the genus and species. The lesson also contains links to the next lesson where molecular phylogeny is described and the three-domain system is covered in greater detail with a focus on the results of Carl Woese’s rRNA study The lesson begins by looking at the meaning of a population in Biology so that the term species can be introduced. A hinny, which is the hybrid offspring of a horse and a donkey, is used to explain how these two organisms must be members of different species because they are unable to produce fertile offspring. Moving forwards, students will learn that classification is a means of organising the variety of life based on relationships between organisms using differences and similarities in phenotypes and in genotypes and is built around the species concept and that in the modern-day classification hierarchy, species is the lowest taxon. A quiz runs throughout the lesson and this particular round will engage the students whilst they learn (or recall) the names of the other 7 taxa and the horse and the donkey from the earlier example are used to complete the hierarchy. Students will understand that the binomial naming system was introduced by Carl Linnaeus to provide a universal name for each species and they will be challenged to apply their knowledge by completing a hierarchy for a modern-day human, by spotting the correct name for an unfamiliar organism and finally by suggesting advantages of this system.

This lesson describes the relationship between the specialised structural features of the mammalian gametes and their functions. The PowerPoint and accompanying resources have been designed to cover point 3.6 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification and includes descriptions of the acrosome in the head of the sperm and the zona pellucida in the egg The lessons at the start of topic 3 (Voice of the genome) described the ultrastructure of eukaryotic cells, so this knowledge is referenced throughout the lesson and the students are challenged on their recall and understanding through a range of prior knowledge checks. For example, two of the exam-style questions that are included in the resources challenge the students to explain why a sperm cell is classified as an eukaryotic cell and to recognise the centrioles and the nucleus from structural descriptions. Along with the mitochondria, time is then taken to discuss and to describe the role of these organelles in relation to the function of the sperm cell. When considering the role of the haploid nucleus, links are made to the upcoming topic of meiosis and the events that contribute to variation. The importance of the enzymes that are found inside the acrosome is emphasised and this leads into the second half of the lesson where the layers surrouding the plasma membrane of the egg cell (corona radiata and zona pellucida) are examined The final part of this lesson has been specifically planned to prepare the students for the next lesson in topic 3, where the acrosome reaction, cortical reaction and the fusion of nuclei that are involved in fertilisation are described

This lesson describes how the surfaces in insects, fish and mammals are adapted for gas exchange. The PowerPoint and accompanying worksheets have been designed to cover the detail of point 4.3 (i) of the Edexcel A-level Biology B specification. The lesson has been intricately planned to challenge the students on their understanding of the surface area to volume ratio (as covered in topic 4.1) and to make direct links to upcoming lessons on the transport systems in humans. The lesson begins by explaining that single-celled organisms are able to diffuse oxygen and carbon dioxide across their body surface but that as organisms increase in size and their SA/V ratio decreases, they need adaptations at their gas exchange surfaces to be able to obtain the oxygen to meet their metabolic demands. This leads into the next part of the lesson which describes the roles of the following structures in insects and bony fish: spiracles, tracheae, tracheoles and tracheole fluid operculum, gill arch, gill filaments and lamellae The next task challenges the students to use their knowledge of topics 1, 2 and 3 to come up with the letters that form the key term, countercurrent flow. This is a key element of the lesson and tends to be a principle that is poorly understood, so extra time is taken to explain the importance of this mechanism. Students are shown two diagrams, where one contains a countercurrent system and the other has the two fluids flowing in the same direction, and this is designed to support them in recognising that this type of system ensures that the concentration of oxygen is always higher in the oxygenated water than in the blood in the lamellae. As the alveoli as a structure of gas exchange was introduced at GCSE, this final part of the lesson has been written to challenge the recall of that knowledge and to build on it. The main focus is the type of epithelium found lining the alveoli and students will discover that a single layer of flattened cells known as simple, squamous epithelium acts to reduce the diffusion distance. Again, students will have met this in a lesson in topic 2 on specialised cells (and tissues) so a number of prior knowledge checks are used alongside current understanding checks. The following features of the alveolar epithelium are also covered: Surface area Moist lining Production of surfactant The maintenance of a steep concentration gradient As a constant ventilation supply is critical for the maintenance of the steep concentration gradient, the final task considers the mechanism of ventilation

This lesson describes how the cells of multicellular organisms are organised into tissues, tissues into organs and organs into systems. The detailed and engaging PowerPoint and accompanying resources have been designed to cover point 3.13 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification and focuses on the levels of organisation in humans and plants The lesson begins by using 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 are challenged to remember how the shape and arrangement of these cells differ in the trachea and alveoli in relation to their function. The link between specialised cells and tissues is made at this point of the lesson so students are reminded that a tissue is a group of cells that work together to perform a specific function or set of functions. Moving forwards, a quick quiz competition will challenge the students to recognise the liver, kidney, spinal cord and pancreas from a brief functional description and this leads into a series of questions that links back to topics 1 and 2 and earlier in topic 3 where blood clotting, proteins, osmosis, organelles, methods of transport, carbohydrates and enzymes were originally covered. These prior knowledge checks are found throughout the lesson, along with current understanding checks, and all of the mark schemes are embedded into the PowerPoint to allow students to assess their progress. In terms of organ systems, a quick task challenges them to recognise 8 of the 11 that are found in humans from descriptions and this leaves them to identify the gaseous exchange, digestive and reproductive systems as the remaining 3. This leads into a section about cystic fibrosis as this genetic disorder impairs the functioning of these systems. The remainder of the lesson focuses on specialised plant cells and the differing shapes and features of the palisade and spongy cells in the mesophyll layer and the guard cells are covered at length and in detail. The cells found in the xylem and phloem tissue are also discussed.

This lesson describes the levels of organisation, including the aggregation of cells into tissues, tissues into organs and organs into organ systems. The detailed and engaging PowerPoint and accompanying resources have been designed to cover point (d) of AS unit 1, topic 2 of the WJEC A-level Biology specification and focuses on the levels of organisation in humans and plants. Please note that the lesson does not contain prepared slides of tissue as this is covered in a later lesson. The lesson begins by using 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 are challenged to remember how the shape and arrangement of these cells differ in the trachea and alveoli in relation to their function. The link between specialised cells and tissues is made at this point of the lesson so students are reminded that a tissue is a group of cells that work together to perform a specific function or set of functions. Moving forwards, a quick quiz competition will challenge the students to recognise the liver, kidney, spinal cord and pancreas from a brief functional description and this leads into a series of questions that links back to topics 1 and earlier in topic 2 where proteins, organelles and carbohydrates were originally covered. These prior knowledge checks are found throughout the lesson, along with current understanding checks, and all of the mark schemes are embedded into the PowerPoint to allow students to assess their progress. In terms of organ systems, a quick task challenges them to recognise 8 of the 11 that are found in humans from descriptions and this leaves them to identify the gaseous exchange, digestive and reproductive systems as the remaining 3. The remainder of the lesson focuses on specialised plant cells and the differing shapes and features of the palisade and spongy cells in the mesophyll layer and the guard cells are covered at length and in detail. The cells found in the xylem and phloem tissue are also discussed.

This lesson describes the structure and functions of the organelles that are found in eukaryotic cells. The engaging and detailed PowerPoint and accompanying resources have been designed to cover point (a) in AS Unit 1, topic 2 of the WJEC A-level Biology specification As cells are the building blocks of living organisms, it makes sense that they would be heavily involved in all 6 modules in the OCR course and intricate planning has ensured that links to the lessons earlier in AS unit 1 are made as well as to the upcoming topics in the other units. The lesson uses a wide range of activities, that include exam-style questions, class discussion points and quick quiz competitions, to maintain motivation and engagement whilst describing the relationship between the structure and function of the following organelles: nucleus nucleolus centrioles ribosomes rough endoplasmic reticulum Golgi body lysosomes smooth endoplasmic reticulum mitochondria cell surface membrane vacuole chloroplasts plasmodesmata All of the worksheets have been differentiated to support students of differing abilities whilst maintaining challenge Due to the detail that is included in this lesson, it is estimated that it will take in excess of 3 hours of allocated A-level teaching time to go through all of the tasks