This lesson describes how to use the Spearman’s rank correlation coefficient to consider the relationship between two sets of data. The PowerPoint and accompanying exam-style question are part of the final lesson in a series of 3 which have been designed to cover point 4.2.2 (f) of the OCR A-level Biology A specification. The previous two lessons described the different types of variation and explained how to calculate the standard deviation and how to use the Student’s t-test to compare two means. As with the previous lesson, a step by step guide is used to walk the students through the use of the formula to generate the rank coefficient and to determine whether there is a positive correlation, no correlation or a negative correlation. The students are also reminded of the null hypothesis and will be shown how to accept or reject this hypothesis and to determine significance. The students will work through an example with the class and then are given the opportunity to apply their newly-acquired knowledge to an exam-style question. The mark scheme is displayed on the PowerPoint so they can assess their understanding

This lesson describes the t-test can be used to compare the variation of two different populations. The detailed PowerPoint and accompanying resources have been designed to cover point 17.1 [c] of the CIE A-level Biology specification and also explains how to calculate the standard deviation to measure the spread of a set of data as this value is needed in the t-test formula A step by step guide walks the students through each stage of the calculation of the standard deviation and gets them to complete a worked example with the class before applying their knowledge to another set of data in an exam-style question. This data looks at the birth weights of humans on one day in the UK and this is used again later in the lesson to compare against the birth weights of babies in South Asia when using the t-test. The null hypothesis is introduced and students will learn to accept or reject this based upon a comparison of their value against one taken from the table based on the degrees of freedom.

This lesson describes how to calculate the standard deviation to measure the spread of a set of data and to compare means using the t-test. The detailed PowerPoint and accompanying resources have been designed to cover the part of point 4.2.2 (f) of the OCR A-level Biology A specification that includes these two statistical tests. A step by step guide walks the students through each stage of the calculation of the standard deviation and gets them to complete a worked example with the class before applying their knowledge to another set of data. This data looks at the birth weights of humans on one day in the UK and this is used again later in the lesson to compare against the birth weights of babies in South Asia when using the student’s t-test. The null hypothesis is introduced and students will learn to accept or reject this based upon a comparison of their value against one taken from the table based on the degrees of freedom.

This lesson describes the principle components of the plasma membrane, focusing on the phospholipid bilayer and membrane proteins. The detailed PowerPoint and accompanying worksheets have been designed to cover the detail in point (a) of AS unit 1, topic 3 of the WJEC A-level Biology specification and clear links are made to Singer and Nicholson’s fluid mosaic model The fluid mosaic model is introduced at the start so that it can be referenced at appropriate points throughout the lesson. Students were introduced to phospholipids in topic 1 and so an initial task challenges them to spot the errors in a passage describing the structure and properties of this molecule. This reminds them of the bilayer arrangement, with the hydrophilic phosphate heads protruding outwards into the aqueous solutions on the inside and the outside of the cell. In a link to some upcoming lessons on the transport mechanisms, the students will learn that only small, non-polar molecules can move by simple diffusion and that this is through the tails of the bilayer. This introduces the need for transmembrane proteins to allow large or polar molecules to move into the cell by facilitated diffusion and active transport. Proteins that act as receptors as also introduced and an opportunity is taken to make a link to an upcoming topic so that students can understand how hormones or drugs will bind to target cells in this way. Moving forwards, the structure of cholesterol is covered and students will learn that this hydrophobic molecule sits in the middle of the tails and therefore acts to regulate membrane fluidity. The final part of the lesson challenges the students to apply their newly-acquired knowledge to a series of questions where they have to explain why proteins may have moved when two cells are used and to suggest why there is a larger proportion of these proteins in the inner mitochondrial membrane than the outer membrane.

This lesson describes the transport mechanism of osmosis as the movement of water molecules from a high water potential to a lower water potential. The PowerPoint and accompanying resources are part of the second lesson in a series of 4 lessons which have been designed to cover point [c] as detailed in AS unit 1, topic 3 of the WJEC A-level Biology specification and also describes how cells are affected by this movement of water It’s likely that students will have used the term concentration in their osmosis definitions at GCSE, so the aim of the starter task is to introduce water potential to allow students to begin to recognise osmosis as the movement of water molecules from a high water potential to a lower potential, with the water potential gradient. Time is taken to describe the finer details of water potential to enable students to understand that 0 is the highest value (pure water) and that this becomes negative once solutes are dissolved. Exam-style questions are used throughout the lesson to check on current understanding as well as prior knowledge checks which make links to previously covered topics such as the lipid bilayer of the cell membrane. The remainder of the lesson focuses on the movement of water when animal and plant cells are suspended in hypotonic, hypertonic or isotonic solutions and the final appearance of these cells is described, including any issues this may cause.

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 the relationship between the specialised features of the mammalian egg and sperm and their functions. The PowerPoint and accompanying resources have been designed to cover point 3.11 of the Edexcel International A-level Biology specification and includes a focus on the acrosome in the head of the sperm and the zona pellucida in the egg The lessons at the start of topic 3 (Cell structure, Reproduction and Development) 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 fusion of the haploid nuclei to form a diploid nucleus in the nucleus, links are made to the upcoming topic of mitosis and the significance of this form of nuclear division. 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 surrounding 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 biodiversity is generated through natural selection and leads to behavioural, anatomical and physiological adaptations. The PowerPoint and accompanying resources have been designed to cover specification points (m) & (n) in AS unit 2, topic 1 of the WJEC A-level Biology 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 evolution through natural selection. The main task of the lesson challenges the students to form a description that explains how this strain of bacteria developed resistance to methicillin to enable them to see the principles of natural selection. This can then be used when describing how the anatomy of the modern-day giraffe has evolved over time. The concept of convergent evolution is introduced and links are made to the need for modern classification techniques as covered earlier in topic 1. Moving forwards, students will understand how natural selection leads to adaptations and a quick quiz competition introduces the different types of adaptation and a series of tasks are used to ensure that the students can distinguish between anatomical, behavioural and physiological adaptations. The Marram grass is used to test their understanding further, before a step by step guide describes how the lignified cells prevent a loss of turgidity. Moving forwards, the students are challenged to explain how the other adaptations of this grass help it to survive in its environment. A series of exam-style questions on the Mangrove family will challenge them to make links to other topics such as osmosis and the mark schemes are displayed to allow them to assess their understanding. The final part of the lesson focuses on the adaptations of the anteater but this time links back to the topic of taxonomy and students have to answer questions about species and classification hierarchy. Due to the extensiveness of this lesson and the detail contained within the resources, it is estimated that it will take in excess of 2 hours of allocated A-level teaching time to deliver this lesson.

This lesson describes the characteristic features of the Animalia, Plantae, Fungi, Protoctista and Prokaryotae kingdoms. The engaging PowerPoint and accompanying resources have been designed to cover point (d) in AS unit 2, topic 1 of the WJEC A-level Biology specification This lesson begins with a knowledge recall as students have to recognise that prior to 1990, kingdom was the highest taxa in the classification hierarchy. Moving forwards, they will recall the names of the five kingdoms and immediately be challenged to split them so that the prokaryotae kingdom is left on its own. An opportunity is taken at this point to check on their prior knowledge of the structure of a bacterial cell as covered in unit 1, topic 2. These prior knowledge checks are found throughout the lesson (along with current understanding checks) as students are also tested on their knowledge of the structure and function of cellulose. This is found in the section of the lesson where the main constituent of the wall can be used to distinguish between plantae, fungi and prokaryotae. Quick quiz competitions, such as YOU DO THE MATH and SAY WHAT YOU SEE are used to introduce key values and words in a fun and memorable way. The final part of the lesson looks at the protoctista kingdom and students will come to understand how these organisms tend to share a lot of animal or plant-like features. Both of the accompanying resources have been differentiated to allow students of differing abilities to access the work and this lesson has been written to tie in with the previously uploaded lesson on classification and the binomial naming system

This lesson describes the gross structure of the human gas exchange system, including the trachea, bronchi, bronchioles and lungs. The PowerPoint and accompanying resources are part of the third lesson in a series of 6 which have been designed to cover the detail of topic 3.2 in the AQA A-level Biology specification which is titled gas exchange and this lesson has been specifically planned to prepare students for the next lesson where the essential features of the alveoli are described. The lesson is filled with a range of activities such as guided discussion periods, exam-style questions (with markschemes) and quiz competitions and these run alongside the slides containing the detailed A-level Biology content to cover the following features: The incomplete rings of cartilage, ciliated pseudostratified columnar epithelium and goblet cells in the trachea The narrowing airways of the primary, secondary and tertiary bronchi The elastic fibres and smooth muscle in the terminal and respiratory bronchioles The pleural cavity and fluid of the lungs When describing the production of mucus by the goblet cells in the trachea, time is taken to consider cystic fibrosis and the inheritance of this autosomal recessive disorder. Students will be supported in working out genotypes from a pedigree tree to prepare them for the topic of inheritance (7.1)

This lesson describes the gross structure of the human gas exchange system and the functions of the structural components like goblet cells. The PowerPoint and accompanying resources have been designed to cover points 9.1 (a & c) of the CIE A-level Biology specification and has been specifically planned to prepare students for an upcoming lesson where the gas exchange between the alveoli and the blood is described. The lesson is filled with a range of activities such as guided discussion periods, exam-style questions (with markschemes) and quiz competitions and these run alongside the slides containing the detailed A-level Biology content to cover the following features: The incomplete rings of cartilage, ciliated pseudostratified columnar epithelium and goblet cells in the trachea The narrowing airways of the primary, secondary and tertiary bronchi The elastic fibres and smooth muscle in the terminal and respiratory bronchioles The pleural cavity and fluid of the lungs When describing the production of mucus by the goblet cells in the trachea, time is taken to consider cystic fibrosis and the inheritance of this autosomal recessive disorder. Students will be supported in working out genotypes from a pedigree tree to prepare them for topic 16 (Inherited change)

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 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