Topic 5 On the wild side This teaching scheme is divided into three parts. Introduction. Road map: a suggested route through Topic 5. Guidance notes for teachers and lecturers. These include a commentary that runs parallel with the student book with hints and tips on teaching and references to the associated activities. Note: There are more detailed notes about individual activities in the teacher/lecturer sheets that accompany most of the activities. Introduction The Road map starting on page 2 is a suggested route through Topic 5. The learning outcomes are numbered as in the specification. If two teachers/lecturers are sharing a group for Topic 5, the first could start at Session 1 with the second starting at Session 11. This means that the second teacher would have a larger chunk of the content. The first teacher could either start the next topic once they have done sessions 1 to 10, or pick up the final sessions 21 23. Care must be taken to link back to the context of climate change and the Arctic if the splitting of the topic is not to end up producing a series of traditional style sub topics. It is assumed that each session is approximately an hour in length. There are more activities than can be done in the time available in most centres, so select a balanced collection according to your and your students interests, and the time and resources available. Some activities are labelled Core. Core activities contain experimental techniques included in the specification, and may appear in questions on the unit exam for this topic. These learning outcomes are in bold in the specification, and in the Road map grid below. They are underlined in the Guidance notes below. In the Road map grid, activities are in italics if there is an additional activity covering the same material more directly. Choose which activities students complete, and substitute your own activities as appropriate. There are various activities particularly the interactive tutorials associated with some of the activities which could be completed by students outside of class time. These activities are shown in the lower half of each Possible activities box. There is an A2 summary chart at the end of the guidance notes. This shows where concepts are introduced and revisited in later topics.. 1
Road map: a route through Topic 5 Session Areas to be covered 1 Ecosystems abiotic and biotic factors Possible activities Introductory presentation (Interactive tutorial) Activity 5.1 The brine shrimp ecosystem (A5.01L) (Practical) 2 3/4 10 Explain that the numbers and distribution of organisms in a habitat are controlled by biotic and abiotic factors. 12 Explain how the concept of niche accounts for distribution and abundance of organisms in a habitat. Studying ecosystems 11 Describe how to carry out a study on the ecology of a habitat to produce valid and reliable data (including the use of quadrats and transects to assess abundance and distribution of organisms and the measurement of abiotic factors, e.g. solar energy input, climate, topography, oxygen availability and edaphic factors). Checkpoint question 5.1 Activity 5.2 Looking for patterns (Core) (A5.02L) (Practical) 5 Succession Activity 5.3 Succession (A5.03L) (Interactive tutorial) 13 Describe the concept of succession to a climax community. Checkpoint question 5.2 6/7/8 Photosynthesis 3 Describe the overall reaction of photosynthesis as requiring energy from light to split apart the strong bonds in water molecules, storing the hydrogen in a fuel (glucose) by combining it with carbon dioxide and releasing oxygen into the atmosphere. 5 Describe how phosphorylation of ADP requires energy and how hydrolysis of ATP provides an immediate supply of energy for biological processes. Activity 5.5 Investigating photosynthesis (Optional) (A5.05L) (Practical) Checkpoint question 5.3 Activity 5.4 Photosynthesis (A5.04L) (Interactive tutorial) Activity 5.6 How Calvin won the Nobel prize (Optional) (A5.06L) 4 Describe the light-dependent reactions of photosynthesis including how light energy is trapped by exciting 2
electrons in chlorophyll and the role of these electrons in generating ATP, and reducing NADP in photophosphorylation and producing oxygen through photolysis of water. 9/10 11 12 6 Describe the light-independent reactions as reduction of carbon dioxide using the products of the lightdependent reactions (carbon fixation in the Calvin cycle, the role of GP, GALP, RuBP and RUBISCO) and describe the products as simple sugars that are used by plants, animals and other organisms in respiration and the synthesis of new biological molecules (including polysaccharides, amino acids, lipids and nucleic acids). 2 Describe the structure of chloroplasts in relation to their role in photosynthesis. Energy flow in the ecosystem 7 Carry out calculations of net primary productivity and explain the relationship between gross primary productivity, net primary productivity and plant respiration. 8 Calculate the efficiency of energy transfers between trophic levels. Evidence for climate change temperature records 18 Analyse and interpret different types of evidence for global warming and its causes (including records of carbon dioxide levels, temperature records, pollen in peat bogs and dendrochronology) recognising correlations and causal relationships. Evidence for climate change pollen in peat bogs 18 Analyse and interpret different types of evidence for global warming and its causes (including records of carbon dioxide levels, temperature records, pollen in peat bogs and dendrochronology) recognising correlations and causal relationships Activity 5.7 Constructing food webs (A5.07L) Activity 5.8 Energy flow in an ecosystem (A5.08L) Checkpoint question 5.4 Activity 5.9 Long datasets: the importance of being trendy (A5.09L) Activity 5.10 Pollen analysis (A5.10L) (Interactive) 3
13 14 Evidence for climate change dendrochronology 18 Analyse and interpret different types of evidence for global warming and its causes (including records of carbon dioxide levels, temperature records, pollen in peat bogs and dendrochronology) recognising correlations and causal relationships The link between carbon dioxide and warming 14 Outline the causes of global warming including the role of greenhouse gases (carbon dioxide and methane, CH4) in the greenhouse effect. Activity 5.11 Tree ring studies (A5.11L) (Interactive tutorial) Activity 5.12 Do higher carbon dioxide levels lead to warmer conditions? (A5.12L) (Practical) Activity 5.13 Carbon dioxide levels and global temperatures (A5.13L) 15 16 17 Controversy surrounding the issue of climate change 20 Discuss the way in which scientific conclusions about controversial issues, such as what actions should be taken to reduce global warming or the degree to which humans are affecting global warming, can sometimes depend on who is reaching the conclusions. Climate modelling 19 Describe that data can be extrapolated to make predictions, that these are used in models of future global warming, and that these models have limitations. (Activity 5.16) Effect of climate change on flora and fauna distribution 15 Describe the effects of global warming (rising temperature, changing rainfall patterns and changes in seasonal cycles) on plants and animals (distribution of species, development and life cycles). Activity 5.15 Who is right? (A5.15L) Optional Activity 5.14 Global warming fact or fiction? (A5.14L) Activity 5.16 Global warming model (A5.16L) (Interactive tutorial) Student research on changing distribution of species using book and Internet. Activity 5.17 Coral bleaching (A5.17L) Optional Checkpoint question 5.5 18 Temperature and enzyme activity 16 Explain the effect of increasing temperature on the rate of enzyme activity in plants, animals and microorganisms. Activity 5.18 Investigating the effect of temperature on enzyme activity (A5.18L) (Practical) 4
19 20 21/22 23 24 Effect of climate change on flora and fauna development 17 Describe how to investigate the effects of temperature on the development of organisms (e.g. seedling growth rate, brine shrimp hatch rates). Effect of climate change on flora and fauna life cycles 15 Describe the effects of global warming (rising temperature, changing rainfall patterns and changes in seasonal cycles) on plants and animals (distribution of species, development and life cycles). Evolution by natural selection molecular evidence 21 Describe how evolution (a change in the allele frequency) can come about through gene mutation and natural selection. 23 Describe the role of the scientific community in validating new evidence (including molecular biology, e.g. DNA, proteomics) supporting the accepted scientific theory of evolution (scientific journals, the peer review process, scientific conferences). Speciation 22 Explain how reproductive isolation can lead to speciation. The carbon cycle 9 Discuss how understanding the carbon cycle can lead to methods to reduce atmospheric levels of carbon dioxide (including the use of biofuels and reforestation). Activity 5.20 The effect of temperature on the hatching success of brine shrimps (Core) (A5.20L) (Practical) Activity 5.19 Effect of climate manipulations on a grassland community (Core) (A5.19L) (Practical) Activity 5.21 Are insects emerging earlier? (A5.21L) (Interactive tutorial) Checkpoint question 5.6 Activity 5.23 Evolution revealed (A5.23L) Activity 5.22 Debunking the myth of the polar bear hair (A5.22L) Activity 5.24 Speciation (A5.24L) (Interactive tutorial) Activity 5.25 The carbon cycle (A5.25L) Checkpoint question 5.7 Guidance notes for teachers and lecturers There are no GCSE style reviews and tests at the start of the A2 topics. Introduction The context for this topic is climate change; this builds on ideas covered in Topic 4 about threats to biodiversity. The topic focuses on the evidence for climate change and the possible consequences for both plants and animals. The introductory spread considers the 5
classic example of the polar bear and associated species in the threatened Arctic ecosystem. The interactive introductory presentation provides an overview of the topic. This presentation is best used as an out-of-class activity if time is likely to be limited. It raises many of the issues that are considered in the topic. There is no introductory activity but an excellent introduction to this issue would be to show the first episode in the BBC series Nature s Great Events. This David Attenborough narrated programme is about the effects of the annual melt on a range of different species including the Polar bear; it goes on to consider the potential impact of climate change. 5.1 What is an ecosystem? Before considering the potential impact of climate change it is necessary to understand what an ecosystem is, and how it functions. In the text book ecosystems and the various ecological terms used to describe their components are discussed, followed by a more detailed consideration of abiotic and biotic factors. Students could be asked to make a table of definitions for the terms. It should quickly become clear that producing a simple definition for ecosystem is not straightforward. It could be defined as a relatively self-contained, interacting community of organisms and the environment in which they live and with which they interact. In the textbook this is initially illustrated using the brine shrimp ecosystem. The term ecosystem itself does not appear in the specification but habitats and the role of abiotic and biotic factors are included. Activity 5.1 The brine shrimp ecosystem (A5.01L) The brine shrimp ecosystem could be used as a demonstration of an ecosystem at the start of this section. This activity lets students identify the key components of an ecosystem and investigate the effects of altering conditions. Enthusiasts could complete the investigation aspects of this activity outside of lessons, rather than using limited class time. Students need to be able to describe how to carry out a study on the ecology of a named habitat and also to explain that the numbers and distribution of organisms in a habitat are controlled by biotic and abiotic factors. There is a link back to niche in Topic 4, students need to explain how the concept of niche accounts for distribution and abundance of organisms in a habitat; this is linked to Checkpoint question 5.1. It is highly desirable for students to obtain first-hand experience of practical fieldwork. This can be a full-scale field course or a small-scale trip onto a school/college field or to the local park. The latter may not provide the opportunity to relate many biotic and abiotic factors to organism distribution but it should provide students with experience of ecological studies. Activity 5.2 Looking for patterns (A5.02L) Core practical This core activity encourages students to plan a field investigation and outlines some techniques for investigating plant and animal distribution. The idea of adaptations allowing organisms to cope with the conditions that prevail in a particular habitat introduced in Topic 4 is revisited here. In the textbook this is illustrated using the rocky shore with some examples of the organisms that are found on different parts of the shore. There is a virtual rocky shore tour on the British Ecological Society website; the website can be found in the weblinks that accompany activity 5.2. Students need to be aware that ecosystems are not static but continually changing. The textbook goes on to consider succession. Activity 5.3 Succession (A5.03L) This activity suggests a variety of possible approaches to look at succession. The interactive tutorial takes students through the process and they complete the accompanying 6
student sheet to provide a summary of succession. At the end of the interactive tutorial, students analyse sand dune data provided within Fieldworks software. Please note that this software can only be used for the data provided; new data cannot be entered. The student sheet also suggests some fieldwork options to enable students to apply the ideas seen in the interactive tutorial and realise that at a given time only a snapshot of an on-going process is available. A fieldwork study undertaken by A level students is also described; this case study includes questions and could be used as a homework exercise. Checkpoint question 5.2 requires students to compare primary and secondary succession and explain what is meant by deflected succession. 5.2 Ecosystems rely on energy transfer The section begins by linking back to the Arctic ecosystem, before going on to look at how an ecosystem works in terms of energy, including photosynthesis and the transfer of energy. The overview of photosynthesis first considers the process in terms of making and breaking bonds and the energy levels of the reactants and products. It then focuses on the underlying principles that hydrogen is removed from water by photolysis and is stored within an organic fuel until the energy it contains is required, and is then released by reacting the hydrogen and oxygen in respiration. The textbook goes on to describe the reactions of photosynthesis; there may appear to be less detail than might sometimes be taught at A level. The aim is for students to concentrate on the key features and not get bogged down with detail that can lead to confusion. For example, neither the textbook nor the interactive tutorial presents the light-independent reactions as a Z-scheme; instead the fundamental idea of transfer of electrons leading to formation of ATP and reduced NADP is stressed. For the more ambitious, the Z-scheme is included in an extension sheet. Respiration appears in Topic 7 and at that point we build on the material presented here in Topic 5, extending understanding of electron transfer by adding the chemiosmotic theory. There are three activities and two extensions associated with the photosynthesis section. The first, Activity 5.4, is an interactive tutorial with associated worksheets to guide the student through photosynthesis. If time permits, Activity 5.5 provides a practical opportunity to reinforce the ideas. Activity 5.6 can be used to confirm understanding of photosynthesis. The specification does not require students to have looked at the structure of the leaf, which is covered in on of the extensions, but they do need to be able to describe the structure of chloroplasts in relation to their role in photosynthesis. Activity 5.4 Photosynthesis (A5.04L) This interactive tutorial takes students through both the light-dependent and lightindependent reactions. There are extensive worksheets that aim to focus students on the relevant concepts as they complete the activity and, on completion, provide summary diagrams and notes. Extension 5.2 Leaf structure and function (X5.02L) This extension relates photosynthesis to the structure of leaves. This is not required knowledge for the Topic 5 specification but should help students recall aspects of Topic 4 such as plant cell structure, lignification for strengthening, and the role of the xylem vessels. Extension 5.3 Light-dependent reactions for the more ambitious (X5.03L) This extension provides a more detailed account of the cyclic and non-cyclic phosphorylation; these terms are not included in the specification. 7
Activity 5.5 Investigating photosynthesis (A5.05L) Optional This practical uses extracted chloroplasts to show the reduction that occurs in the lightindependent stage of photosynthesis. Interpretation of the results should confirm students understanding of the reactions in photosynthesis. Activity 5.6 How Calvin won the Nobel prize (A5.06L) Optional The experimental techniques used by Calvin to elucidate the reactions of photosynthesis are described. Students apply their knowledge of photosynthesis when interpreting simplified results. The textbook goes on to consider the transfer of energy through the ecosystem. It starts with feeding relationships and although these are not stated as a learning outcome in the specification, they underpin the ideas of transfer of energy in an ecosystem. Food chains and webs seem to be covered at every key stage and so this is really recall from KS3 and KS4. A very brief reminder might be all that is needed in class to confirm students understanding of trophic levels and introduce any new terminology; they may not be familiar with autotrophs and heterotrophs. Checkpoint question 5.4 could be used in a subsequent session to check learning. Activity 5.7 Constructing food webs (A5.07L) The textbook describes the terminology associated with feeding relationships and this activity is a simple paper-based exercise in which students draw out a food web based on a series of feeding relationship statements. There are suggestions in the teacher/lecturer notes for video and CD-ROM resources that could be used here. This activity can be completed out of class. Activity 5.8 Energy flow in an ecosystem (A5.08L) The textbook defines gross and net primary productivity before discussing the efficiency of energy transfer. This activity complements the textbook, looking at the energy budget of a bullock and at energy flow through an ecosystem. 5.3 Is the climate changing? The topic now moves on to climate change. It first looks at the scientific evidence for climate change both in the past and present. Each type of evidence described in the textbook is accompanied by an activity. Activity 5.9 Long datasets: the importance of being trendy (A5.09L) The activity looks at long-term temperature records; it also aims to give students practice in interpretation of data presented in graphical form. Q5.23 in the textbook also appears in the activity. Activity 5.10 Pollen analysis (A5.10L) The textbook describes the process of pollen analysis and how it provides evidence for changes in climate. In this activity students examine a virtual sediment sample. The student sheet can be completed using either the interactive version or the downloaded pollen and tree information sheets. Activity 5.11 Tree ring studies (A5.11L) This activity has an interactive tutorial showing how tree ring studies can be used to help date old wood and deduce past climates. Putting the data together The final part of this section in the textbook brings together the different sources of evidence to provide a picture of conditions over more than 100 000 years, with the changes in atmospheric temperature over the last hundred years provided in more detail. The Climate Research Unit at the University of East Anglia regularly updates the temperature data on 8
their website. A weblink to the site can be found in the weblinks that accompany Activity 5.9. Students need to look at the graphs and realise that we are in a period of rapid global warming although this is not the only period of warming in the past. 5.4 Why are global temperatures changing? The role of the atmosphere in maintaining warm, stable temperatures on Earth is described at the start of this section. Students should be familiar with this from KS4 so a spot test/quiz should be sufficient to refresh memories. A diagram with missing information could be used. Activity 5.12 could be introduced before it is completed in the next session. Activity 5.13 could be started prior to the practical and completed as a homework assignment. Carbon dioxide is often held up as the culprit in current global warming. The experiment in Activity 5.12 helps investigate whether raised levels of carbon dioxide can lead to atmospheric warming. The textbook compares carbon dioxide with other gases, showing that it is not only carbon dioxide that is involved in global warming. Activity 5.12 Do higher carbon dioxide levels lead to warmer conditions? (A5.12L) Milk bottles are used in this experiment to investigate if there is a link between carbon dioxide and warming. The experiment on the student sheet describes how datalogging can be used but the experiment can also be undertaken using conventional thermometers. Activity 5.13 Carbon dioxide levels and global temperatures (A5.13L) Students gain more experience comparing and interpreting a range of graphs and discuss possible relationships between atmospheric carbon dioxide levels and global warming. A controversial issue The reasons why climate change is controversial are described in the textbook, which highlights the idea that scientific conclusions about controversial issues can sometime depend on who is reaching the conclusion. The activities provide the opportunity to evaluate writing published about the issue of global warming. Activity 5.14 Global warming fact or fiction? (A5.14L) The first part of this activity provides a framework for evaluating the views expressed in published articles. The articles in Activity 5.15 could be used for this part of the activity although some shorter recent articles would be better. Students do not have to learn the statements in the grid; rather, they need to realise that information presented may be influenced by the position held by the individual or organisation expressing the view. The information from the CO 2 Climate Resource Centre on the archived Greening Earth Society website which illustrates this point could be downloaded and used as handouts if Internet access is difficult. The second half of the activity involving Internet research can be quite time consuming. Activity 5.15 Who is right? (A5.15L) Optional This discussion-based activity can be an alternative to the previous activity. 5.5 Predicting future climates This section of the textbook discusses the ideas behind extrapolation and prediction. It allows students to use a computer model of climate change and consider the limitations of such models. Activity 5.16 Global warming model (A5.16L) This interactive model gives students the chance to appreciate the complexity of climate modelling. Scientists undertaking research into climate change use several models. Predictions from these models can be seen at the University of East Anglia Climate Research Unit and the 9
Meteorological Office Hadley Centre websites. Weblinks accompany Activity 5.16. Some computer models give very different predictions of climate change; this is referred to in the textbook in the section titled Climate model predicts a colder UK. This highlights the fact that there are no definitive answers as yet, only predictions based on models derived using available evidence. 5.6 Coping with climate change This section considers the effects of climate change on flora and fauna (plants and animals). It is divided into two parts; the changing distribution of species and the effects on development and life cycles. Activity 5.17 Coral bleaching (A5.17L) Optional This activity provides a detailed example of one group of animals that appear to be affected by climate change. The activity uses the US Department of Commerce sea surface records to investigate the occurrence of coral bleaching and the potential link to global warming. The US National Oceanic and Atmospheric Administration NOAA/NESOIS website is constantly updated and if the link does not immediately go to the appropriate page, look for coral bleaching which has a link to the 1998 data. Extension 5.5 (X5.05S) looks at how the extinction of the dinosaurs may have been caused by climate change. The first page of the activity can also be used when introducing the idea that scientific theories must be supported by evidence. There is an excellent article in New Scientist covering the major theories for the extinction of the dinosaurs: Ravilious K. (2002) Killer blow. New Scientist, 2341, 28 31. Changing distribution of species There is evidence that the distribution of species will change as a result of global warming with (in the northern hemisphere) a northwards shift. The textbook gives some examples of changing species distribution and raises some of the problems that may result. Students could be asked to research species for themselves using the Internet and share their findings with the group. The effects of rising temperature on plant growth and photosynthesis are discussed in relation to the effect of temperature on enzymes involved in photosynthesis. A Key biological principle box describes the effect of temperature on enzyme activity and there is an associated activity. Activity 5.18 Investigating the effect of temperature on enzyme activity (A5.18L) The student activity sheet is a planning sheet for an investigation on the effect of temperature on catalase activity. A suggested experimental set-up is included in the teacher/lecturer notes. Activity 5.19 Effect of climate manipulations on a grassland community (A5.19L) Core practical The activity describes the experimental design of a field investigation into the effects of different temperature and rainfall conditions on the growth of grassland plants. The research data are from the Unit of Comparative Plant Ecology at the University of Sheffield, kindly supplied to us by Professor Philip Grimes. The activity highlights the difficulty of predicting ecological consequences because of interacting factors. This is also discussed in the textbook. Students can see the experimental plots at Buxton, near Sheffield, via their webcam. This activity can be used to for the core practical requirement of specification point 17 Describe how to investigate the effects of temperature on the development of organisms (e.g. seedling growth rate, brine shrimp hatch rates). 10
Activity 5.20 The effect of temperature on the hatching success of brine shrimps (A5.20L) Core practical The experiment in this activity is likely to show a fairly straightforward relationship between temperature and hatching success. This activity can be used as the core practical for the learning outcome 17 Describe how to investigate the effects of temperature on the development of organisms (e.g. seedling growth rate, brine shrimp hatch rates). Activity 5.21 Are insects emerging earlier? (A5.21L) The effects of global warming on seasonal events are investigated using an online datasets for the first appearance of insect species and mean flight times, and the UK phenology website interactive garden. The need for long-term data to provide evidence of changes in seasonal events is emphasised in the textbook. Checkpoint 5.5 requires students to summarise the effects of climate change on plants and animals. 5.7 Adapt or die Linking back to polar bears and whether they will cope with the changing conditions, adaptation and evolution by natural selection are revisited. The textbook outlines Darwin s observations and conclusions to summarise his theory. The text links back to the ideas presented in Topic 4 about evolution as a change in allele frequency over time. It may be sufficient to recall the ideas using Checkpoint 5.6, this requires student to explain how natural selection can lead to evolution. The text book goes on to discuss the role of the scientific community in validating new evidence, this is linked to the work of Darwin but the principles remain the same for molecular evidence for evolution. This evidence is described in the textbook. Activity 5.22 Debunking the myth of the polar bear hair (A5.22L) This activity is a discussion style activity based around a series of statement cards. The statements are linked to adaptations of polar bears, it includes the much published idea that Polar bear hairs act as fibre optics transferring energy through their hollow shaft to the skin surface. This suggestion was not based on experimental evidence and the aim of the activity is to get students to appreciate the process of validating evidence. The associated specification point is not about polar bear hair, but concerned with molecular evidence for evolution. This type of How Science Works outcome can appear in any context within the unit papers so presenting it in one context and then referring to it again in Activity 5.23 will help prepare students for questions on HSW that are not presented in the obvious context presented in the specification statement. Activity 5.23 Evolution revealed (A5.23L) The amino acid sequence of cytochrome C is used to illustrate molecular evidence for evolution. Students are also referred to the DNAtoDarwin which uses case studies to explore DNA sequences evidence for evolution. The idea of validating new evidence should be linked to in this activity. The text book questions whether climate change will result in the formation of new species and discusses speciation. Activity 5.24 Speciation (A5.24L) The interactive tutorial accompanying this activity presents an example of reproductive isolation leading to speciation. Students work through the tutorial and then write a summary. 5.8 Getting the balance right There is no traditional detailed description of the processes in the carbon cycle within the textbook. As most students are likely to have come across the carbon cycle in previous 11
courses and in the GCSE review it was felt that a lengthy account was not required. There is a Key biological principle box that contains a carbon cycle diagram and the accompanying question provides definitions of the processes involved in the cycle. The aim is to encourage a more thoughtful approach; the student must look at the carbon cycle diagram and think about the cycle. Activity 5.25 The carbon cycle (A5.25L) In this activity students are made aware of the size of the different carbon fractions by calculating their percentage of the total carbon in the global ecosystem. The students then construct a carbon cycle diagram. There are questions about the movement of carbon through the different carbon reservoirs. The activity seeks to encourage students to think about the carbon cycle in a way that moves on from anything done at GCSE. The School Science review article Making the invisible visible: monitoring levels of gaseous carbon dioxide in the field and classroom. By Roger Delpech uses CO 2 sensors and dataloggers to monitor CO 2 levels in a range of situations. Factors that upset the carbon balance are described in the textbook and reforestation and the use of biofuels as methods to maintain the balance are discussed. Students do not need to know the detailed production or chemistry of biofuels. Checkpoint 5.7 requires student to think through the pros and cons of the methods discussed. Activity 5.26 Check your notes Students can use the checklist of learning outcomes in this activity in their revision. End-of-topic tests There is an online interactive end-of-topic test. This test is not accessible to students unless set by their teacher/lecturer. There is also a paper-based test for Topic 5 with examinationstyle questions. A mark scheme is also available. The questions are similar in layout and style to those that are found on exam papers. However, the restriction of questions to only one topic in each test has meant that it has not been possible to include some types of questions that draw on material from different topics. 12
A2 Summary chart The grid below shows where concepts are introduced and then revisited in later topics. Note: Some of these concepts will be revisited from AS and built on in A2 in addition to those that are discrete to A2. Italics show where additional synoptic links could be made during teaching. Concept Topic 5 Topic 6 Topic 7 Topic 8 Biological molecules (monomers combine to form polymers) products of photosynthesis Complementary protein structure T cell receptors, antigens, antibodies, CD4 and gp120 receptors Protein structure sliding filaments, (actin, myosin, etc.) and electron carriers Protein structure ion channels, neurotransmitters Enzymes Rubisco Effect of temperature on rate of enzyme-controlled reactions DNA polymerase Reverse transcriptase Integrase ATPase Respiration enzymes including cytochrome oxidase Acetylcholinesterase Chemical reactions Cell structure Genes help determine the nature of organisms Reduction Oxidation Phosphoprylation Plant cell structure Structure of chloroplast Prokaryotic cell ultrastructure (bacteria) Viruses Phagocytes, neutrophils, macrophages Lymphocytes Eukaryotic cell ultrastructure Genetic code Protein synthesis Post-transcriptional changes HIV control of transcription/ protein synthesis Dehydrogenation Decarboxylation Reduction Oxidation Phosphoprylation Muscle fibres types Mitochondria structure Control of gene expression by transcription factors Neurones and Schwann cells Genetically modified organisms Cell cycle HIV lifecycle Stem cells Energy Transport in and out of cells Photosynthesis ATP synthesis Energy balance, BMR ATP synthesis Respiration: aerobic and anaerobic Electron transport chain and chemiosmosis Muscle fibres Hormones Na + /K + pumps Movement of ions in action potential and rod cells Synapses/neurotransmitters 13
Concept Topic 5 Topic 6 Topic 7 Topic 8 Transport in Transport in plants Cardiovascular system heart rate, organisms to and from cardiac output Control of ventilation exchange Transport of energy by surfaces cardiovascular system Organisms exchange materials with the environment Gas exchange in plants (surface area to volume ratio) Properties of gas exchange surfaces Gas exchange Inheritance Genetic variation (STRs) Inheritance of phenotype for success in endurance/sprint events Gene DNA profiling technology Polymerase chain reaction Evolution and natural selection Adaptation Evolution by natural selection Speciation Changing distribution of species with climate change Natural selection and evolution of pathogens and host Classification Bacteria and viruses Interactions with the environment Energy flow and recycling of materials in ecosystems Ecosystems Distribution of organisms (biotic and abiotic factors) Adaptations Niche Succession Effect of global warming on animals and plants (distribution of species, development and lifecycles) Causes of global warming GPP NPP Respiration Energy flow Efficiency of energy transfer Sustainable resource utilisation The carbon cycle Global warming Adaptations for endurance or sprint activity fast and slow twitch fibres 14 Multifactoral diseases Genetic modification Outcomes of the Human Genome Project Genetically modification Succession on corpses Nature and nurture effects on brain development Critical windows for visual development Carbon cycle decomposition of corpses Coordination Sliding filament theory for muscle contraction Electrical activity of the heart Control cardiac output and ventilation Homeostasis temperature regulation Negative feedback The carbon cycle Nervous control Action potential Impulse conduction Positive feedback Synapses Stimulus detection Reflex arcs Learning habituation Hormonal co-ordination Co-ordination in plants (role of IAA)
Concept Topic 5 Topic 6 Topic 7 Topic 8 Light detection and responses in plants (phytochromes) Risk and perception Risk of infection/vaccination Risk of cardiovascular disease, obesity and diabetes Maths/science skills Health and disease Ecological sampling Statistics Data analysis and interpretation Calculating rates Recognise correlations and causal relationships Use theories, models and ideas to develop and modify scientific explanations Scientific consensus and evidence Extrapolation, prediction and modelling Scientific conclusions about controversial issues can depend on who is reaching the conclusion Validating evidence Appreciate the tentative nature of scientific knowledge Analyse and interpret evidence data for time of death Cardiovascular disease Symptoms of bacterial (TB) and viral infection (HIV) Immunity (non-specific and specific) Barriers to infection Active, passive, artificial and natural immunity The effect of antibiotics Hospital acquired infections Calculating cardiac output, lung volumes, ventilation and respiration rates Recognise correlations and causal relationships related to exercising too much or too little Use theories, models and ideas to develop and modify scientific explanations Disadvantages of too much exercise immune suppression, joint damage Disadvantages of too little exercise CHD, increased risk of obesity and diabetes Use of animal models Benefits and risks of GMO use Brain chemical imbalances Ethics Use of performance-enhancing drugs Use of animals in medical research Use of genetically modified organisms Applications of biology Methods to reduce CO 2 levels Forensic pathology Forensic entomology Drug development antibiotics Vaccination Prevention and control of hospital acquired infections ECGs Medical technology (key-hole surgery and prosthetics) Uses of MRI, fmri and CT scans Effect of drugs on synaptic transmission Drug development 15