This revision resource has been designed to cover the content in both topic 11 (Gas exchange) and topic 12 (Respiration) of the CIE IGCSE Biology specification for examination in June and November 2020 and 2021. The topics have been combined because of the huge crossover and the aim was to encourage students to see those connections and to make the Biological links. The resource contains an engaging and detailed PowerPoint (77 slides) and associated worksheets, some of which have been differentiated to provide assistance for those students who need it. Included in the resource are exam questions, quick tasks and quiz competitions which try to cover as much content as possible with the following areas receiving particular attention: The internal and external structure of the trachea The structure of the alveoli to allow efficient gas exchange The role of the ribs, intercostal muscles and diaphragm in ventilation The differences in composition between inspired and expired air Aerobic respiration in seeds The uses of energy in the body of humans Anaerobic respiration and the oxygen debt This resource contains a large emphasis on the mathematical element of the Biology course. Students are guided through key skills such as percentage change and then challenged to apply

This concise, engaging revision lesson has been designed to include activities that will motivate the students whilst they assess their understanding of topic B3 (Biological molecules) of the CIE IGCSE Combined Science specification. An understanding of biological molecules is fundamental to the understanding of a lot other Biology topics and this lesson has attempted to make the links between the different areas. The range of activities which include exam questions, quick tasks and quiz competitions have been written to cover as much of the content as possible but the following topics have received particular attention: The chemical elements in carbohydrates The formation of starch and glycogen from glucose The iodine test for starch Lipids are formed of fatty acids and glycerol Investigational skills The ethanol emulsion test for lipids This resource includes a PowerPoint (27 slides) and a worksheet with a task about the digestion of milk fat so students can recognise the components of lipids

This fully-resourced lesson has been designed to cover the content found in specification point 5.2.3 (The eye) of topic 5 of the AQA GCSE Biology specification. This resource contains an engaging and detailed PowerPoint (46 slides) and accompanying worksheets, some of which have been differentiated to help students of different abilities to take on the task. The lesson begins with a game of IMPOSSIBLE (shown in the picture) where students are challenged to pick out the names of the 7 structures of the eye which the specification states they have to be able to identify on a diagram. Students are given the functions of the cornea and the sclera to guide them at the start of the labelling task before they have to use their previous knowledge of the nervous system to write a function for the optic nerve. Literacy and numeracy skills are tested throughout the lesson and the next round of the quiz challenges them to use synonyms to recognise the key terms of adaptation and accommodation. Time is taken to focus on the process of accommodation so that students can see how the ciliary muscles and suspensory ligaments interact to change the shape of the lens and allow both near and distant objects to be seen clearly. This takes the lesson nicely into the next section where the conditions of myopia and hyperopia are considered. Again, the students are challenged on their recognition of Biology terminology to spot that these are the medical names for short and long-sightedness. Students are guided through the correction of myopia before being challenged to write a letter to the mother of a girl who suffers from hyperopia, explaining how the lens is used to correct the defect. As stated at the top, this lesson has been designed for GCSE-aged students who are studying the AQA GCSE Biology course, but can be used with younger students who are keen to learn about the eye or with A-level students who need to go back over the key points.

This lesson has been designed to cover the higher tier content of specification point 5.3.4 (Hormones in human reproduction) which is found in topic 5 of the AQA GCSE Biology & Combined Science specifications. A wide range of activities will engage and motivate the students whilst the content is covered in detail and understanding checks are included at regular points to enable the students to self-assess their new found knowledge. The following Biology is covered in this lesson: Reproductive hormones in the development of secondary sexual characteristics The role of testosterone as the main male reproductive hormone The role of oestrogen and progesterone in the repair and maintenance of the uterus lining The role of FSH and LH in the maturation of an egg and ovulation The interaction of these four hormones in the control of the menstrual cycle The final part of the lesson involves a number of questions where the students are challenged to apply their knowledge to unfamiliar situations This lesson has been designed for GCSE-aged students who are taking the AQA GCSE Biology or Combined Science course but it is also suitable for younger students who are looking into this topic as part of the reproduction module

This resource contains a concise, engaging PowerPoint and accompanying worksheets which together cover the content of specification point 7.3 (Thyroxine and the control of metabolic rate as an example of negative feedback) as found on the Edexcel GCSE Biology & Combined Science higher tier specifications. Over the course of the lesson, students will learn about the effects of the release of thyroxine, how this release is regulated by the pituitary gland and hypothalamus and also will understand how this control is an example of negative feedback. Due to the obvious connection to the previously learned endocrine system topic, regular opportunities are taken to check on this prior knowledge and these work well with the understanding checks which allow the students to assess their progress. A quiz competition called FROM NUMBERS 2 LETTERS is used to introduce the key abbreviations in a fun and memorable way, whilst the key details of the content is always at the forefront of the design of the lesson. This lesson has been written for students studying the higher tier of the Edexcel GCSE Biology or Combined Science courses but it is also suitable for use with A-level students who need to recall the key details of these two hormones

This lesson resource contains a engaging PowerPoint and accompanying worksheets, all of which have been designed to cover the content of specification point 2.5 (d) on the WJEC GCSE Biology specification. This specification point states that students should know the components of a reflex arc. This lesson builds on the knowledge from the previous lesson on the structure and function of the nervous system (2.5b). The lesson begins by challenging the students to come up with the word reflex having been presented with 5 other synonyms of the word automatic. This leads into a section of discovery and discussion where students are encouraged to consider how a reflex arc can be automatic and rapid despite the fact that the impulse is conducted into the CNS like any other reaction. Students will be introduced to the relay neurone and will learn how this provides a communication between the sensory neurone and the motor neurone and therefore means that these arcs do not involve processing by the brain. Moving forwards, the main task of the lesson challenges the students to write a detailed description of a reflex arc. Assistance is given on the critical section which involves the relay neurone in the spinal cord before they have to use their knowledge of nervous reactions to write a paragraph before and after to complete the description. As a final task, students will have to compare the structure and functions of sensory, motor and relay neurones. Although this lesson has been designed for students studying on WJEC GCSE Biology course, it is also suitable for older students who are studying reflex reactions at A-level and need to recall the main details.

This concise lesson presentation and accompanying worksheet have been designed to cover the content of point 2.5 (h) of the WJEC GCSE Biology specification which states that students should understand the need to keep blood glucose levels within a constant range. Homeostasis is a running theme throughout the 2.5 topic so this lesson builds on knowledge from earlier topics to ensure that there is a deep understanding. The lesson begins by introducing glucose and a quiz competition will lead to the range 4 - 7, so that students can recognise that this is the set range within which this molecule’s concentration must be kept. Time is taken to look at some of the health problems that are associated with an increase in concentration above this upper limit and the general Biological knowledge of the students is tested with some questions. Moving forwards, the main task of the lesson involves a step by step guide through the stages in the response to a high blood glucose concentration and shows the students how the release of insulin leads to the uptake of glucose from the blood and a conversion to glycogen by the liver and muscle cells. The summary task at the end challenges the students to bring all of the information together to write a detailed description of this response and this activity is differentiated to aid those students who need extra assistance. This lesson has been designed for students studying the WJEC GCSE Biology course but could be used with A-level students who are beginning this topic and need to recall the key details.

This is a fully-resourced lesson which covers the detail of point 5.1.3 (b) of the OCR A-level Biology A specification which states that students should be able to apply their understanding of the structures and functions of sensory, relay and motor neurones as well as the differences between myelinated and unmyelinated neurones. 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 also distinguish between them based on their structural features. Time is taken to look at the importance of the myelin sheath for the sensory and motor neurones. Students will be introduced to the need for the entry of ions to cause depolarisation and will learn that this is only possible at the nodes of Ranvier when there is a myelin sheath. Key terminology such as saltatory conduction is introduced and explained. 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, links are made to the upcoming topic of the organisation of the nervous system (5.1.5) and students will be given additional knowledge such as the differences between somatic and autonomic motor neurones. This lesson has been designed for students studying on the OCR A-level Biology A course.

This lesson has been designed to cover the content of the 1st part of specification point 6.1.2 of the AQA A-level Biology specification which states that students should know the basic structure of a Pacinian corpuscle and be able to use its function as a representation of sensory receptors. By the end of the lesson students will understand that sensory receptors respond to specific stimuli and how a generator potential is established. The lesson begins by using a quiz to get the students to recognise the range of stimuli which can be detected by receptors. This leads into a task where the students have to form 4 sentences to detail the stimuli which are detected by certain receptors and the energy conversion that happen as a result. Students will be introduced to the idea of a transducer and learn that receptors always convert to electrical energy which is the generator potential. The remainder of the lesson focuses on the Pacinian corpuscle and how this responds to pressure on the skin. The involvement of sodium and potassium ions is introduced so discussions on how the membrane potential changes from resting potential in the establishment of a generator potential are encouraged. This lesson has been written for students studying on the AQA A-level Biology course and ties in nicely with other uploaded lessons which cover the content of topic 6

This engaging REVISION LESSON has been designed to cover the content of topic 13 (Photosynthesis) of the CIE International A-level Biology specification. Filled with a wide range of activities, that include exam questions with explanations, quick tasks and quiz competitions, the students will be motivated whilst they assess their ability to apply their knowledge. Due to the obvious importance of this reaction, assessment questions are extremely common and so a deep understanding of this topic is key to success and the lesson has been designed to cover the important ideas. The following sub-topics have received particular attention in this lesson: Photophosphorylation An outline of cyclic and non-cyclic photophosphorylation Photolysis of water The light dependent reaction The structure of the chloroplast and the site of the different reactions The Calvin cycle The limiting factors of photosynthesis Investigating the effect of light intensity using DCPIP as a redox indicator and a Hill suspension The effect of temperature on the rate There is a focus on terminology throughout the lesson so that students are comfortable with the terms that will be encountered in exam questions. Revision lessons on the other topics of the specification are uploaded so please take a moment to look at those too

This detailed and engaging REVISION LESSON has been written to cover the content of topic 4 (Cell membranes and transport) of the CIE International A-level Biology specification. The lesson consists of a PowerPoint that contains exam questions, differentiated tasks and quiz competitions and is accompanied by worksheets with further activities. The competitions act to engage the students whilst they assess their understanding of the content and challenges their ability to apply this knowledge to potentially unfamiliar situations. The lesson was designed to cover as much of the specification content as possible but the following sub-topics have received particular attention: Active transport and its applications in animals and plants Facilitated diffusion and the use of channel and carrier proteins The factors that affect diffusion as demonstrated by gas exchange at the alveoli Exocytosis Water potential and the movement of water by osmosis The effect of solutions of different water potentials on animal and plant tissue The fluid mosaic model The plasma cell membrane and the function of its components As well as covering the current topic, the design of this lesson has been conscious to include future topics. For example, a cholinergic synapse was used to challenge the students to spot examples of facilitated diffusion, simple diffusion, active transport and exocytosis. Revision lessons for the other 18 topics are uploaded on TES or are in the process of being uploaded.

This fully-resourced REVISION LESSON has been designed to provide the students with numerous opportunities to assess their understanding of the content of topic 12 (Energy and respiration) of the CIE International A-level Biology specification. The importance of this metabolic reaction is obvious and this is reflected in the volume of questions in the terminal exams which require an in depth knowledge of the stages of both aerobic and anaerobic respiration. The lesson contains a wide range of activities that cover the following points of the specification: Glycolysis as a stage of aerobic and anaerobic respiration The use and production of ATP through respiration Anaerobic respiration in mammalian muscle tissue The stages of aerobic respiration that occur in the mitochondrial matrix Oxidative phosphorylation The use of respirometers Calculating the respiratory quotient value for different substrates Revision lessons which cover the other topics of the specification are also uploaded and tie in well with this lesson.

This fully-resourced lesson guides students through the use of the Hardy-Weinberg equation to calculate the frequency of alleles, genotypes and phenotypes in a population. Both the detailed PowerPoint and differentiated practice questions on a worksheet have been designed to cover the 2nd part of point 7.2 of the AQA A-level Biology specification which expects students to be able to use this mathematical model The lesson begins by looking at the equation and ensuring that students understand the meaning of each of the terms. The recessive condition, cystic fibrosis, is used as an example so that students can start to apply their knowledge and assess whether they understand which genotypes go with which term. Moving forwards, a step-by-step guide is used to show students how to answer a question. Tips are given during the guide so that common misconceptions and mistakes are addressed immediately. The rest of the lesson gives students the opportunity to apply their knowledge to a set of 3 questions, which have been differentiated so that all abilities are able to access the work and be challenged.

This fully-resourced lesson explores sex-linkage and specifically the inheritance of sex-linked diseases in humans and then challenges the students to apply their knowledge to examples in other animals. The detailed PowerPoint and associated differentiated resources have been designed to cover the part of point 16.2 (b) of the CIE International A-level Biology specification which states that students should be able to use genetic diagrams to solve problems involving sex-linkage. 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 tasks of the lesson challenge the students to carry out a dihybrid cross that involves a sex-linked disease and an autosomal disease before applying their knowledge to a 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 markschemes to allow them to assess their progress and address any misconception

This fully-resourced REVISION lesson has been designed to enable the students to challenge their knowledge of the content of topic 16 (Inherited change) of the CIE A-level Biology specification. The engaging PowerPoint and accompanying differentiated worksheets will motivate the students whilst they assess their understanding of the content and identify any areas which may require further attention. The wide range of activities have been written to cover as much of the topic as possible but the following specification points have been given particular focus: Homologous pairs of chromosomes The meanings of haploid and diploid The behaviour of chromosomes in meiosis Crossing over and random assortment as causes of genetic variation The use of key genetic terminology The use of genetic diagrams to solve problems including autosomal and sex-linkage, dihybrid inheritance and gene interactions The use of the chi-squared test Gene mutations Genetic control of protein production in prokaryotes Gibberellins and how they cause the breakdown of DELLA proteins Due to the extensiveness of this resource, it is likely that it will take a number of lessons to go through all of the activities

This fully-resourced lesson focuses on the role of meiosis in ensuring genetic variation through the production of non-identical gametes. The detailed PowerPoint and accompanying resource have been designed to cover point 3.9 of the Pearson Edexcel A-level Biology (Salters Nuffield) specification which states that students should be able to describe how crossing over and independent assortment result in genetically unidentical daughter cells. In order to understand how the events of meiosis like crossing over and random 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 segregation of chromosomes and chromatids during anaphase I and II results in genetically different gametes. 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 questions which challenge the students to apply their knowledge to potentially unfamiliar situations.

This lesson focuses on the nature of the genetic code and specifically focuses on the degenerate nature to make a link to gene mutations which is covered later in topic 2. The PowerPoint has been designed to cover point 2.7 of the Pearson Edexcel A-level Biology (Salters Nuffield) specification which states that students should understand how the descriptive terms triplet code, degenerate and non-overlapping relate to the genetic code. The lesson begins by introducing the terms near universal and non-overlapping in addition to degenerate. A quick quiz competition is used to generate the number 20 so that the students can learn that there are 20 proteinogenic amino acids in the genetic code. This leads into a challenge, where they have to use their prior knowledge of DNA to calculate the number of different DNA triplets (64) and the mismatch in number is then discussed and related back to the lesson topic. Moving forwards, substitutions and deletions are briefly introduced so that they can see how although one substitution can change the primary structure, another will change the codon but not the encoded amino acid. The lesson concludes with a brief look at the non-overlapping nature of the code so that the impact of a base deletion can be understood when covered in greater detail with cystic fibrosis

This fully-resourced lesson covers the meaning of the 9 genetic terms that are detailed in point 2.13 (i) of the Pearson Edexcel A-level Biology (Salters Nuffield) specification as well as four other key terms which will need to be used later in topic 2, 3 and 8. In the following lessons, students are expected to be able to demonstrate and apply their knowledge and understanding of genetic diagrams and phenotypic ratios to show patterns of inheritance and this is only possible with a clear understanding of the genetic terminology that will be used in related exam questions. As some of these terms were met at GCSE, this lesson has been designed to build on this prior knowledge and provide clear explanations as to their meanings as well as numerous examples of their use in both questions and exemplary answers. The main task provides the students with an opportunity to apply their understanding by recognising a dominance hierarchy in a multiple alleles characteristic and then calculating a phenotypic ratio when given a completed genetic diagram. Other tasks include prior knowledge checks, discussion points to encourage students to consider the implementation of the genetic terms and quiz competitions to introduce new terms, maintain engagement and act as an understanding check. The 13 terms are genome, gene, chromosome, gene locus, homologous chromosomes, alleles, dominant, recessive, genotype, phenotype, homozygotes and heterozygotes

This is a fully-resourced lesson which looks at the inheritance of genes that are carried on the sex chromosomes in sex-linkage. Students will explore sex-linked diseases in humans and then are challenged to apply their knowledge to examples in other animals. The detailed PowerPoint and associated resources have been designed to cover the second part of point 3.8 (ii) of the Pearson Edexcel A-level Biology (Salters Nuffield) specification which states that students should understand sex-linkage. 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 tasks of the lesson challenge the students to apply their knowledge to a question about chickens and how the rate of feather production in chicks can be used to determine gender.