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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.

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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.
Reproductive isolation, allopatric & sympatric speciation (Edexcel A level Biology B)
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Reproductive isolation, allopatric & sympatric speciation (Edexcel A level Biology B)

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This fully-resourced lesson describes how reproductive isolation can lead to allopatric and sympatric speciation. The engaging PowerPoint and accompanying resources have been designed to cover point 3.2 (iii) of the Edexcel A-level Biology B specification. The lesson begins by using the example of a hinny, which is the hybrid offspring of a horse and a donkey, to challenge students to recall the biological classification of a species. Moving forwards, students are introduced to the idea of speciation and the key components of this process, such as isolation and selection pressures, are covered and discussed in detail. Understanding and prior knowledge checks are included throughout the lesson to allow the students to not only assess their progress against the current topic but also to make links to earlier topics in the specification. Time is taken to look at the details of allopatric speciation and how the different mutations that arise in the isolated populations and genetic drift will lead to genetic changes. The example of allopatric speciation in wrasse fish because of the isthmus of Panama is used to allow the students to visualise this process. The final part of the lesson considers sympatric speciation and again a wide variety of tasks are used to enable a deep understanding to be developed.
Conduction along myelinated axons (Edexcel A-level Biology B)
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Conduction along myelinated axons (Edexcel A-level Biology B)

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This fully-resourced lesson explains why the speed of transmission along myelinated axons is greater than along non-myelinated axons. The PowerPoint and accompanying resources have been designed to cover point 9.5 (iii) of the Edexcel A-level Biology B specification which states that students should understand the role of saltatory conduction in the transmission of action potentials. A wide range of activities have been written into this resource to maintain the motivation of the students whilst ensuring that the detail is covered in real depth. Interspersed with the activities are understanding checks and prior knowledge checks to allow the students to not only assess their understanding of the current topic but also challenge themselves to make links to earlier topics such as the movement of ions across membranes and biological molecules. Time at the end of the lesson is also given to future knowledge such as the involvement of autonomic motor neurones in the stimulation of involuntary muscles. Over the course of the lesson, students will learn and discover the myelin sheath wrapped around the axons of sensory and motor neurones allows these neurones to conduct impulses quickly between receptors and the CNS and between the CNS and effectors. There is a focus on this myelin sheath and specifically how the insulation is not complete all the way along which leaves gaps known as the nodes of Ranvier which allow the entry and exit of ions. Saltatory conduction is poorly understood (and explained) by a lot of students so time is taken to look at the way that the action potential jumps between the nodes and this is explained further by reference to local currents. The rest of the lesson focuses on the other two factors which are axon diameter and temperature and students are challenged to discover these two by focusing on the vampire squid.
Excitatory & inhibitory postsynaptic potentials (Edexcel A-level Biology B)
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Excitatory & inhibitory postsynaptic potentials (Edexcel A-level Biology B)

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This detailed lesson describes the formation and effects of excitatory and inhibitory postsynaptic potentials . The PowerPoint has been designed to cover point 9.5 (v) of the Edexcel A-level Biology B specification. This is a topic which is generally poorly understood by students or brushed over so considerable time has been taken to design the activities to motivate the students so that the content is memorable whilst still being covered in detail. Links are continually made to earlier topics in this topic such as synapses and generator potentials but also to topics covered in the previous year. The lesson begins by challenging the students to recognise a description of generator potential and they will then discover that this is also known as an EPSP. Students will recall that a small depolarisation may not lead to the opening of the voltage gated channels and therefore the full depolarisation which is needed for the initiation of an action potential and will discuss how this problem could be overcome. Lots of discussion points like this are included in the lesson to encourage the students to challenge and debate why a particular process of mechanism occurs. Students will therefore learn that EPSPs can be combined and this is known as summation. A quiz round is used to introduce temporal and spatial summation. Moving forwards, students are presented with a number of examples where they have to decide why type of summation is involved. Again, the lesson has been written to include real-life examples such as chronic pain conditions so the chances of the content sticking is increased. The final part of the lesson introduces IPSPs and the effect of these on summation and action potentials is discussed.
Sensory, relay and motor neurones (Edexcel Int. A-level Biology)
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Sensory, relay and motor neurones (Edexcel Int. A-level Biology)

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This lesson describes the structure and functions of the sensory, relay and motor neurones. The engaging PowerPoint and accompanying resources have been designed to cover point 8.1 of the Edexcel International A-level Biology specification but also considers the organisation of the nervous system into the central and peripheral nervous systems and therefore also covers point 8.10. The PowerPoint has been designed to contain a wide range of activities that are interspersed between understanding and prior knowledge checks that allow the students to assess their progress on the current topics as well as challenge their ability to make links to topics from earlier in the modules. Quiz competitions like SAY WHAT YOU SEE are used to introduce key terms in a fun and memorable way. The students will be able to compare these neurones based on their function but time is taken to distinguish between them based on their structural features. The importance of the myelin sheath for the sensory and motor neurones is briefly discussed and students are introduced to key terminology such as saltatory conduction and Schwann cells so they are prepared for the upcoming lesson covering specification point 8.5. The final task involves a comparison between the three neurones to check that the students have understood the structures and functions of the neurones. Throughout the lesson, the organisation of the nervous system is discussed and students are provided with additional knowledge such as the differences between somatic and autonomic motor neurones.
Module 5.1.1: Communication and homeostasis (OCR A-level Biology A)
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Module 5.1.1: Communication and homeostasis (OCR A-level Biology A)

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This bundle of 4 lessons covers the content of module 5.1.1 of the OCR A-level Biology A specification, titled communication and homeostasis. As this module tends to be one of the first to be taught in the second year of the course, it’s extremely important that links are made to upcoming topics as well as challenging the students on their prior knowledge of modules 2 - 4. This is achieved through a wide range of tasks, that include exam-style questions, differentiated tasks and guided discussion periods. Quick quiz competitions are also used to introduce key terms and values in a fun and memorable way. The following specification points are covered by the 4 lesson PowerPoints and accompanying resources included in this bundle: The communication between cells by cell signalling The principles of homeostasis The differences between negative and positive feedback The physiological and behavioural responses involved in temperature control in endotherms and ectotherms As detailed above, these lessons have been specifically planned to tie in with the other parts of module 5, including neuronal communication, hormonal communication and animal and plant responses. If you would like to sample the quality of the lessons in this bundle, then download the principles of homeostasis and temperature control in ectotherms lessons as these have been uploaded for free
Osmosis and water potential (WJEC A-level Biology)
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Osmosis and water potential (WJEC A-level Biology)

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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.
Action potential (Edexcel Int. A-level Biology)
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Action potential (Edexcel Int. A-level Biology)

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This lesson explains how a nerve impulse (action potential) is conducted along an axon and focuses on the role of the sodium and potassium ions. The PowerPoint and accompanying resources have been designed to cover point 8.4 of the Edexcel International A-level Biology specification and contains detailed descriptions of resting potential, depolarisation, repolarisation, hyperpolarisation and the refractory period. This topic is commonly assessed in the terminal exams so extensive planning ensures that this resource includes a wide range of activities to motivate and engage the students whilst ensuring that the content is covered in the depth of detail that will allow them to have a real understanding. Interspersed within the activities are understanding checks and prior knowledge checks to enable the students to not only assess their progress against the current topic but also to challenge themselves on the links to earlier topics such as methods of movements across cell membranes. There are also a number of quiz competitions which are used to introduce key terms and values in a fun and memorable way and discussion points to encourage the students to consider why a particular process or mechanism occurs. Over the course of the lesson, the students will learn and discover how the movement of ions across the membrane causes the membrane potential to change. They will see how the resting potential is maintained through the use of the sodium/potassium pump and potassium ion leakage. There is a real focus on depolarisation to allow students to understand how generator potentials can combine and if the resulting depolarisation then exceeds the threshold potential, a full depolarisation will occur. At this point in the lesson students will discover how the all or nothing response explains that action potentials have the same magnitude and that instead a stronger stimulus is linked to an increase in the frequency of the transmission. The rest of the lesson challenges the students to apply their knowledge to explain how repolarisation and hyperpolarisation result and to suggest advantages of the refractory period for nerve cells.
Kidney failure and its potential treatments (WJEC A-level Biology)
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Kidney failure and its potential treatments (WJEC A-level Biology)

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This fully-resourced lesson describes the range of potential treatments for kidney failure. The PowerPoint and accompanying resources have been designed to cover specification point (h) in topic 7 of A2 unit 3 of the WJEC A-level Biology specification. This lesson involves the diagnosis of a number of different kidney-related conditions and the potential treatments for kidney failure. This lesson is designed to get the students to take on the numerous roles of a doctor who works in the renal ward which include testing, diagnosis and treatment. Having obtained measurements by GFR and results by taking urine samples, hey are challenged to use their knowledge of the function of the kidney to study urine samples (and the accompanying GP’s notes) to diagnose one of four conditions. They then have to write a letter to the patient to explain how they made this diagnosis, again focusing on their knowledge of the structure and functions of the Bowman’s capsule and PCT. The rest of the lesson focuses on haemodialysis, peritoneal dialysis and kidney transplant. There are regular progress checks throughout the lesson so that students can assess their understanding and there are a number of homework activities included in the lesson.
Chi squared test (WJEC A-level Biology)
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Chi squared test (WJEC A-level Biology)

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This lesson guides students through the use of a chi-squared test to determine the significance of the difference between observed and expected results. It is fully-resourced with a detailed PowerPoint and differentiated worksheets that have been designed to cover point (d) in topic 3 of A2 unit 4 of the WJEC A-level Biology specification The lesson includes a step-by-step guide to demonstrates how to carry out the test in small chunks. At each step, time is taken to explain any parts which could cause confusion and helpful hints are provided to increase the likelihood of success in exam questions on this topic. Students will understand how to use the phenotypic ratio to calculate the expected numbers and then how to find the critical value in order to compare it against the chi-squared value. A worked example is used to show the working which will be required to access the marks and then the main task challenges the students to apply their knowledge to a series of questions of increasing difficulty. This lesson has been specifically designed to tie in with the previous lessons in this topic as there are regular references to dihybrid inheritance as well as to topics in the AS units like meiosis
Osmosis and the effect on cells (CIE International A-level Biology)
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Osmosis and the effect on cells (CIE International A-level Biology)

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This detailed lesson describes how the movement of water between solutions and cells has differing effects on animal and plant cells. Both the PowerPoint and accompanying resources have been designed to cover specification points 4.2 (a) and (f) as detailed in the CIE International A-level Biology specification. 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.
Mitosis (Edexcel A-level Biology B)
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Mitosis (Edexcel A-level Biology B)

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This fully-resourced lesson describes the events of the cell cycle so that students can understand how the genetic material behaves in interphase, mitosis and cytokinesis. The detailed PowerPoint and accompanying resources have been designed to cover specification points 2.3 (i), (ii) and (iii) as detailed in the Edexcel A-level Biology B specification. Depending upon the exam board taken at GCSE, the knowledge and understanding of mitosis and the cell cycle will differ considerably between students and there may be a number of misconceptions. This was considered at all points during the planning of the lesson and to address existing errors, key points are emphasised throughout. The cell cycle is introduced at the start of the lesson and the quantity of DNA inside the parent cell is described as diploid and as 2n. A quiz competition has been written into the lesson and this runs throughout, challenging the students to identify the quantity of DNA in the cell (in terms of n) at different points of the cycle. Moving forwards, the first real focus is interphase and the importance of DNA replication is explained so that students can initially recognise that there are pairs of identical sister chromatids and then can understand how they are separated later in the cycle. The main part of the lesson focuses on prophase, metaphase, anaphase and telophase and describes how the chromosomes behave in these stages. An exam style question will check on their knowledge of the organelles from 2.1 and this acts to remind them that centrioles are responsible for the production of the spindle apparatus, Students will understand how the cytoplasmic division that occurs in cytokinesis results in the production of genetically identical daughter cells. This leads into a series of understanding and application questions where students have to identify the various roles of mitosis in living organisms as well as tackling a Maths in a Biology context question. The lesson concludes with a final round of MITOSIS SNAP where they only shout out this word when a match is seen between the name of a phase, an event and a picture
The importance of water (WJEC A-level Biology)
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The importance of water (WJEC A-level Biology)

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This detailed lesson describes the properties of water to demonstrate the importance of this molecule for living organisms. The engaging PowerPoint and accompanying resource have been designed to cover the details of specification point (b) of AS unit 1, topic 1 of the WJEC A-level Biology course and has been specifically designed to ensure that each role is illustrated using a specific example. As this is only the second lesson in the biological compounds topic, which is a topic that students tend to find difficult or potentially less engaging, the planning has centred around the inclusion of a wide variety of tasks to cover the content whilst maintaining motivation and engagement. These tasks include current understanding and prior knowledge checks, discussion points and quick quiz competitions to introduce key terms and values in a memorable way. The start of the lesson considers the structure of water molecules, focusing on the covalent and hydrogen bonds, and the dipole nature of this molecule. Time is taken to emphasise the importance of these bonds and this property for the numerous roles of water and then over the remainder of the lesson, the following properties are described and discussed and linked to real-life examples: polarity ability to form hydrogen bonds surface tension as a solvent thermal properties as a metabolite The final part of the lesson introduces condensation and hydrolysis reactions and students will learn that a clear understanding of these reactions is critical as they will reappear throughout the topic in the synthesis and breakdown of biological compounds
Contraction of skeletal muscle (Edexcel Int. A-level Biology)
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Contraction of skeletal muscle (Edexcel Int. A-level Biology)

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This fully-resourced lesson describes the process of contraction of skeletal muscle in terms of the sliding filament theory. The PowerPoint and accompanying resources have been designed to cover point 7.11 of the Edexcel International A-level Biology specification and includes descriptions of the role of actin, myosin, troponin, tropomyosin, calcium ions, ATP and ATPase. The lesson begins with a study of the structure of the thick and thin filaments. Students will recognise that the protruding heads of the myosin molecule are mobile and this enables this protein to bind to the binding sites when they are exposed on actin. This leads into the introduction of troponin and tropomyosin and key details about the binding of calcium to this complex is explained. Moving forwards, students are encouraged to discuss possible reasons that can explain how the sarcomere narrows during contraction when the filaments remain the same length. This main part of the lesson goes through the main steps of the sliding filament model of muscle contraction and the critical roles of the calcium ions and ATP are discussed. The final task of the lesson challenges the students to apply their knowledge by describing the immediate effect on muscle contraction when one of the elements doesn’t function correctly. This lesson has been written to tie in with the previous lesson on the structure of skeletal muscle fibre (point 7.10)
Excretion
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Excretion

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This is an engaging and informative lesson that looks at the meaning of excretion in detail and explores the functions of the organs involved with the excretion of carbon dioxide and urea. This lesson has been designed for students studying A-level Biology. The lesson begins by introducing the definition of excretion to the students so that they are able to recognise that the substances being removed have to have come from a metabolic process in order to be excreted. This important difference to egestion (elimination) is a key detail which they need to understand at this level. Moving forwards, a quick competition is used to meet some of the organs that are involved in excretion. The remainder of the lesson focuses on the excretion of carbon dioxide. Links are made to the transport of carbon dioxide as hydrogen carbonate ions and how the affinity of haemoglobin for oxygen is affected when the carbon dioxide concentration is high. Students will meet the idea of deamination and the ornithine cycle and the key details of these two processes are covered. Progress checks have been written into this lesson at regular intervals, which challenge the students on knowledge from this lesson and prior knowledge, to enable them to constantly assess their understanding.
Synapses (Pearson Edexcel A-level Biology)
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Synapses (Pearson Edexcel A-level Biology)

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This fully-resourced lesson has been designed to cover point 8.4 of the Pearson Edexcel A-level Biology A (Salters Nuffield) specification that states that students should know the structures and function of synapses in nerve impulse transmission. The majority of the lesson uses the cholinergic synapse as the example but other neurotransmitters are considered to provide the students with a wider view of this topic and to make links to specification point 8.15 The lesson begins by using a version of the WALL (as shown in the cover image) which asks the students to group 12 words into three groups of 4. Not only will this challenge their prior knowledge from topics earlier in this module but it will also lead to the discovery of four of the structures that are found in a synapse. Moving forwards, students are introduced to aectylcholine as the neurotransmitter involved at cholinergic synapses and they will start to add labels to the structures found in the pre-synaptic bulb. Time is taken to focus on certain structures such as the voltage gated channels as these types of channel were met previously when looking at the depolarisation of a neurone. There is plenty of challenge and discovery as students are pushed to explain why organelles like mitochondria would be found in large numbers in the bulb. With this process being a cascade of events, a bullet point format is used to ensure that the key content is taken in by the students and again key points like exocytosis and the action of acetylcholinesterase are discussed further. The final part of the lesson challenges the application aspect of the specification as students are introduced to unfamiliar situations in terms of synapses with new drugs like MDMA and are asked to work out and explain how these affect the nervous transmission. Understanding checks and prior knowledge checks are included throughout the lesson so that students can not only assess their progress against the current topic but also see whether they can make links to earlier topics.
PAPER 2 REVISION FOUNDATION TIER (OCR Combined Science)
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PAPER 2 REVISION FOUNDATION TIER (OCR Combined Science)

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This is a fully-resourced lesson which uses exam-style questions, quiz rounds, quick tasks and discussion points to challenge students on their understanding of the content of topics B4 - B6, that will assessed on PAPER 2. It has been specifically designed for students on the OCR Gateway A GCSE Combined Science course who will be taking the FOUNDATION TIER examinations but is also suitable for students taking the higher tier who need to ensure that the fundamentals are known and understood. The lesson has been written to take place at the hospital and the students will visit the various wards and health clinics day to check on their knowledge of the following sub-topics : Cancer The production of gametes by meiosis The meaning of diploid and haploid Sex determination The difference between communicable and non-communicable diseases Diseases caused by bacteria, viruses, fungi and protists Treatment of bacterial infections using antibiotics Evolution by natural selection in bacteria Vaccinations Genetic terminology Inheritance of disorders caused by dominant and recessive alleles Risk factors of non-communicable diseases Ecosystems The carbon cycle and the increase in carbon dioxide levels In order to maintain challenge whilst ensuring that all abilities can access the questions, the majority of the tasks have been differentiated and students can ask for extra support when they are unable to begin a question. Step-by-step guides have also been written into the lesson to walk students through some of the more difficult concepts such as genetic diagrams and interpreting the results and evolution by natural selection. Due to the extensiveness of this revision lesson, it is estimated that it will take in excess of 3 teaching hours to complete the tasks and therefore this can be used at different points throughout the duration of the course as well as acting as a final revision before the PAPER 2 exam.
The significance of water (Edexcel A-level Biology B)
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The significance of water (Edexcel A-level Biology B)

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This detailed lesson describes the importance of the dipole nature of water and its numerous properties to living organisms. The engaging PowerPoint and accompanying resource have been designed to cover the details of specification point 1.7 of the Edexcel A-level Biology B course and the intricate planning ensures that each role is illustrated using a specific example. As the final lesson in the biological molecules topic, not only does this lesson cover the important content related to water but also acts as a revision tool as it checks on key topic 1 content such as condensation and hydrolysis reactions. A wide range of tasks are used to check on current understanding and prior knowledge and quick quiz competitions introduce key terms and values in a memorable way. The start of the lesson considers the structure of water molecules, focusing on the covalent and hydrogen bonds, and the dipole nature of this molecule. Time is taken to emphasise the importance of these bonds and this property for the numerous roles of water and then over the remainder of the lesson, the following properties are described and discussed and linked to real-life examples: high specific heat capacity polar solvent surface tension incompressibility maximum density at 4 degrees Celsius
Ex situ conservation (Edexcel A-level Biology B)
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Ex situ conservation (Edexcel A-level Biology B)

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This lesson describes the principles of ex situ conservation and discusses the advantages and issues surrounding this method. The PowerPoint and accompanying worksheet are part of the second lesson in a series of 2 which have been designed to cover the content of point 3.3 (iii) of the Edexcel A-level Biology B specification and it closely ties in with the previous lesson on in situ conservation. To enrich their understanding of ex situ conservation, the well-known examples of ZSL London zoo, Kew Gardens and the Millennium Seed Bank Project in Wakehurst are used. Students will understand how conserving animal species outside of their natural habitat enables human intervention that ensures the animals are fed and given medical assistance when needed as well as reproductive assistance to increase the likelihood of the successful breeding of endangered species. As with the in situ method in the previous lesson, the issues are also discussed and there is a focus on the susceptibility of captive populations to diseases as a result of their limited genetic diversity. The final part of the lesson considers how seed banks can be used to ensure that plant species avoid extinction and how the plants can be bred asexually to increase plant populations quickly.
The main stages and significance of mitosis (WJEC A-level Biology)
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The main stages and significance of mitosis (WJEC A-level Biology)

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This lesson describes the main stages of mitosis and explains the significance of this type of nuclear division for the daughter cells produced by the cycle. The PowerPoint and accompanying resources have been designed to cover points 6 (a & b) in topic 6 of AS unit 1 of the WJEC A-level Biology specification and the process of cytokinesis is also described. Depending upon the exam board taken at GCSE, the knowledge and understanding of mitosis will differ considerably between students and there may be a number of misconceptions. This was considered at all points during the planning of the lesson so that existing errors are addressed and key points are emphasised throughout. Their understanding of interphase is challenged at the start of the lesson to ensure that they realise that it is identical pairs of sister chromatids that enter the M phase. The main part of the lesson focuses on prophase, metaphase, anaphase and telophase and describes how the chromosomes behave in these stages. There is a focus on the centrioles and the spindle fibres that they produce which contract to drag one chromatid from each pair in opposite directions to the poles of the cell. The remainder of the lesson is a series of understanding and application questions where students have to identify the various roles of mitosis in living organisms as well as tackling a Maths in a Biology context question. The lesson concludes with a final quiz round of MITOSIS SNAP where they only shout out this word when a match is seen between the name of a phase, an event and a picture.
Meiosis (WJEC A-level Biology)
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Meiosis (WJEC A-level Biology)

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This lesson describes the main stages of meiosis and has a specific focus on those events which contribute to genetic variation. The detailed PowerPoint and accompanying resources have been designed to cover point (d) in topic 6 of AS unit 1 of the WJEC A-level Biology specification and includes description of crossing over, independent assortment, independent segregation and the production of haploid gametes In order to understand how the events of meiosis like crossing over and independent assortment and independent segregation can lead to variation, students need to be clear in their understanding that DNA replication in interphase results in homologous chromosomes as pairs of sister chromatids. Therefore the beginning of the lesson focuses on the chromosomes in the parent cell and this first part of the cycle and students will be introduced to non-sister chromatids and the fact that they may contain different alleles which is important for the exchange that occurs during crossing over. Time is taken to go through this event in prophase I in a step by step guide so that the students can recognise that the result can be new combinations of alleles that were not present in the parent cell. Moving forwards, the lesson explores how the independent assortment and segregation of chromosomes and chromatids during metaphase I and II and anaphase I and II respectively results in genetically different gametes. The key events of all of the 8 phases are described and there is a focus on key terminology to ensure that students are able to describe genetic structures in the correct context. The final part of the lesson looks at the use of a mathematical expression to calculate the possible combinations of alleles in gametes as well as in a zygote following the random fertilisation of haploid gametes. Understanding and prior knowledge checks are interspersed throughout the lesson as well as a series of exam-style questions which challenge the students to apply their knowledge to potentially unfamiliar situations. This lesson has been specifically planned to lead on from the previous two lessons on the cell cycle and the main stages of mitosis and constant references are made throughout to encourage students to make links and also to highlight the differences between the two types of nuclear division