Edexcel International GCSE (9-1) Biology Student Book PDF

EDEXCEL INTERNATIONAL GCSE (9 –1) Uncorrected proof, all content subject to change at publisher discretion. Not for res...

EDEXCEL INTERNATIONAL GCSE (9 –1) Uncorrected proof, all content subject to change at publisher discretion. Not for resale, circulation or distribution in whole or in part. ©Pearson 2019 BIOLOGY EDEXCEL INTERNATIONAL GCSE (9 –1) Student Book Philip Bradfield and Steve Potter EDEXCEL INTERNATIONAL GCSE (9 –1) CHEMISTRY Student Book Jim Clark, Steve Owen, Rachel Yu eBook included Pearson Edexcel International GCSE (9–1) Biology prepares students for the new 2017 International GCSE (9–1) Biology specification. This resource provides comprehensive coverage of the new specification. This book, which includes access CHEMISTRY to the eBook, is designed to provide students with the best preparation possible for Student Book the examination: ISBN: 9780435185169 BIOLOGY Student Book Written by highly experienced International GCSE Biology teachers and authors Content is mapped to the specification to provide comprehensive coverage Exam practice throughout, with differentiated revision exercises and exam-style practice Signposted transferable skills Track progress with the Pearson Progression Scale Reviewed by a language specialist to ensure the book is written in a clear and EDEXCEL INTERNATIONAL GCSE (9 –1) accessible style PHYSICS Glossary of key biology terminology Full answers included on the eBook Student Book Brian Arnold, Penny Johnson, Steve Woolley eBook included EDEXCEL INTERNATIONAL GCSE (9 –1) BIOLOGY eBook included Teacher support materials available online PHYSICS Student Book For Pearson Edexcel International GCSE Biology specification (4BI1) for first ISBN: 9780435185275 teaching 2017 Student Book Philip Bradfield and Steve Potter www.pearsonglobalschools.com eBook included 9780435185084_BiologyCover.indd 1-3 25/04/2017 14:15  Online access to your ActiveBook Thank you for buying this Edexcel International GCSE (9-1) Biology Student Book. Uncorrected proof, all content subject to change at publisher discretion. Not for resale, circulation or distribution in whole or in part. ©Pearson 2019 It comes with three years’ access* to your ActiveBook – an online, digital version of your textbook. You can personalise your ActiveBook with notes, highlights and links to your wider reading. It is perfect for supporting your coursework and revision activities. *For new purchases only. If this access code has already been revealed, it may no longer be valid. If you have bought this textbook second hand, the code may already have been used by the first owner of the book. How to access your ActiveBook Scratch the panel off with a coin to reveal your unique access code. Do not use a knife or other sharp object 1 as it may damage the code. 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If you have any questions about accessing your ActiveBook, please contact our ActiveLearn support site at www.pearsonactivelearn.com/support 9780435185084_BiologyCover.indd 4-5 25/04/2017 14:15  Uncorrected proof, all content subject to change at publisher discretion. Not for resale, circulation or distribution in whole or in part. ©Pearson 2019 Steve Potter F01_EDIB_SB_IGCSE_85084_PRE_i-ix.indd 1 Philip Bradfield Student Book BIOLOGY EDEXCEL INTERNATIONAL GCSE (9 –1) 25/04/2017 11:18  Published by Pearson Education Limited, 80 Strand, London, WC2R 0RL. Pearson examiners have not contributed to any sections in this resource relevant to examination papers for which they have responsibility. Uncorrected proof, all content subject to change at publisher discretion. 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Cover images: Front: Alamy Stock Photo: Cultura RM / Alamy Stock Photo tl Endorsement does not cover any guidance on assessment activities or processes (e.g. practice questions or advice on how to answer assessment questions), All other images © Pearson Education included in the resource nor does it prescribe any particular approach to the teaching or delivery of a related course. Disclaimer: neither Pearson, Edexcel nor the authors take responsibility for the safety of any activity. Before doing any practical activity you are legally required While the publishers have made every attempt to ensure that advice on the to carry out your own risk assessment. In particular, any local rules issued by your qualification and its assessment is accurate, the official specification and employer must be obeyed, regardless of what is recommended in this resource. associated assessment guidance materials are the only authoritative source of Where students are required to write their own risk assessments they must always information and should always be referred to for definitive guidance. be checked by the teacher and revised, as necessary, to cover any issues the students may have overlooked. The teacher should always have the final control as to how the practical is conducted. F01_EDIB_SB_IGCSE_85084_PRE_i-ix.indd 2 25/04/2017 11:18  CONTENTS iii Uncorrected proof, all content subject to change at publisher discretion. Not for resale, circulation or distribution in whole or in part. ©Pearson 2019 COURSE STRUCTURE iv ABOUT THIS BOOK vi ASSESSMENT OVERVIEW viii UNIT 1: ORGANISMS AND LIFE PROCESSES 2 UNIT 2: ANIMAL PHYSIOLOGY 39 UNIT 3: PLANT PHYSIOLOGY 135 UNIT 4: ECOLOGY AND THE ENVIRONMENT 187 UNIT 5: VARIATION AND SELECTION 227 UNIT 6: MICROORGANISMS AND GENETIC MODIFICATION 281 APPENDICES APPENDIX A: A GUIDE TO EXAM QUESTIONS ON EXPERIMENTAL SKILLS 303 APPENDIX B: COMMAND WORDS 308 GLOSSARY 309 INDEX 320 F01_EDIB_SB_IGCSE_85084_PRE_i-ix.indd 3 25/04/2017 11:18  iv COURSE STRUCTURE UNIT 1 Uncorrected proof, all content subject to change at publisher discretion. Not for resale, circulation or distribution in whole or in part. ©Pearson 2019 ORGANISMS AND LIFE PROCESSES 1 LIFE PROCESSES 03 1.1, 2.2, 2.3, 2.4, 2.11, 2.13, 2.12, 2.36, 2.14B, 2.34, 2.35, 2.37, 2.39, 2.15, 2.16, 2.17, 2.5B, 2.1, 2.6B 2 THE VARIETY OF LIVING ORGANISMS 25 1.2, 1.3, 1.4 UNIT 2 ANIMAL PHYSIOLOGY 3 BREATHING AND GAS EXCHANGE 39 2.46, 2.47, 2.48, 2.50, 2.49 4 FOOD AND DIGESTION 52 2.7, 2.8, 2.9, 2.24, 2.25, 2.26, 2.27, 2.28, 2.29, 2.30, 2.31, 2.32, 2.33B 5 BLOOD AND CIRCULATION 70 2.51, 2.52, 2.69, 2.65, 2.67, 2.66, 2.68, 2.59, 2.60, 2.61, 2.62, 2.63B, 2.64B 6 COORDINATION 84 2.80, 2.82, 2.87, 2.86, 2.88, 2.91, 2.92, 2.90, 2.89 7 CHEMICAL COORDINATION 98 2.86, 2.94, 2.95B 8 HOMEOSTASIS AND EXCRETION 104 2.81, 2.71, 2.70, 2.79B, 2.72B, 2.73B, 2.74B, 2.75B, 2.77B, 2.76B, 2.78B, 2.93 9 REPRODUCTION IN HUMANS 118 3.1, 3.2, 3.8, 3.11, 3.12, 3.13, 3.9, 3.10B UNIT 3 PLANT PHYSIOLOGY 10 PLANTS AND FOOD 135 2.23, 2.18, 2.19, 2.21, 2.42B, 2.41B, 2.44B, 2.20, 2.45B, 2.22 11 TRANSPORT IN PLANTS 152 2.15, 2.17, 2.55B, 2.56B, 2.54, 2.53, 2.70, 2.57, 2.58B 12 CHEMICAL COORDINATION IN PLANTS 168 2.83, 2.84, 2.85 13 REPRODUCTION IN PLANTS 174 3.1, 3.7, 3.3, 3.4, 3.6, 3.5 F01_EDIB_SB_IGCSE_85084_PRE_i-ix.indd 4 25/04/2017 11:18  COURSE STRUCTURE v UNIT 4 Uncorrected proof, all content subject to change at publisher discretion. Not for resale, circulation or distribution in whole or in part. ©Pearson 2019 ECOLOGY AND THE ENVIRONMENT 14 ECOSYSTEMS 187 4.1, 4.2, 4.3B, 4.4B, 4.5, 4.6, 4.7, 4.8, 4.9, 4.10, 4.11B 15 HUMAN INFLUENCES ON THE ENVIRONMENT 204 5.1, 5.2, 5.3, 5.4, 5.9B, 4.13, 4.14, 4.15, 4.12, 4.18B, 4.16, 4.17 UNIT 5 VARIATION AND SELECTION 16 CHROMOSOMES, GENES AND DNA 227 3.15, 3.14, 3.16B, 3.17B, 3.18B, 3.34, 3.35B, 3.36B, 3.37B, 3.32, 3.19 17 CELL DIVISION 240 3.28, 3.29, 3.30, 3.31, 3.33 18 GENES AND INHERITANCE 249 3.19, 3.20, 3.23, 3.25, 3.24, 3.21B, 3.26, 3.27, 3.22 19 NATURAL SELECTION AND EVOLUTION 261 3.38, 3.39 20 SELECTIVE BREEDING 268 5.10, 5.11, 5.17B, 5.18B, 5.19B, 5.20B UNIT 6 MICROORGANISMS AND GENETIC MODIFICATION 21 USING MICROORGANISMS 281 5.5, 5.6, 5.7, 5.8 22 GENETIC MODIFICATION 289 5.16, 5.12, 5.13, 5.14, 5.15, 5.20B APPENDICES 303 GLOSSARY 309 F01_EDIB_SB_IGCSE_85084_PRE_i-ix.indd 5 25/04/2017 11:18  vi ABOUT THIS BOOK ABOUT THIS BOOK Uncorrected proof, all content subject to change at publisher discretion. Not for resale, circulation or distribution in whole or in part. ©Pearson 2019 This book is written for students following the Edexcel International GCSE (9–1) Biology specification and the Edexcel International GCSE (9–1) Science Double Award specification. You will need to study all of the content in this book for your Biology examinations. However, you will only need to study some of it if you are taking the Double Award specification. The book clearly indicates which content is in the Biology examinations and not in the Double Award specification. To complete the Double Award course you will also need to study the Physics and Chemistry parts of the course. In each unit of this book, there are concise explanations and worked examples, plus numerous exercises that will help you build up confidence. The book also describes the methods for carrying out all of the required practicals. The language throughout this textbook is graded for speakers of English as an additional language (EAL), with advanced Biology-specific terminology highlighted and defined in the glossary at the back of the book. A list of command words, also at the back of the book, will help you to learn the language you will need in your examination. You will also find that questions in this book have Progression icons and Skills tags. The Progression icons refer to Pearson's Progression scale. This scale – from 1 to 12 – tells you what level you have reached in your learning and will help you to see what you need to do to progress to the next level. Furthermore, Edexcel have developed a Skills grid showing the skills you will practise throughout your time on the course. The skills in the grid have been matched to questions in this book to help you see which skills you are developing. Both skills and Progression icons are not repeated where they are same in consecutive questions. You can find Pearson's Progression scale at www.pearsonglobalschools.com/ igscienceprogression along with guidelines on how to use it. Looking Ahead tells you what you would learn Learning Objectives if you continued your show what you will learn study of Biology to a in each lesson. higher level, such as International A Level. Biology only features show the content that is on the Biology specification only and Key Point boxes not the Double Award summarise the specification. All other essentials. content in this book applies to Double Award students. F01_EDIB_SB_IGCSE_85084_PRE_i-ix.indd 6 25/04/2017 11:18  ABOUT THIS BOOK vii Uncorrected proof, all content subject to change at publisher discretion. Not for resale, circulation or distribution in whole or in part. ©Pearson 2019 Practicals describe the methods for carrying out Extension work boxes include content that is not on the specification all of the practicals you will need to know for and which you do not have to learn for your examination. However, your examination. the content will help to extend your understanding of the topic. Skills tags tell you which skills Chapter Questions test your Progression icons show the level of Unit Questions test your knowledge you are practising in each knowledge of the topic in that difficulty according to the Pearson of the whole unit and provide question. chapter. International GCSE Science quick, effective feedback on your Progression Scale. progress. F01_EDIB_SB_IGCSE_85084_PRE_i-ix.indd 7 25/04/2017 11:18  viii ASSESSMENT OVERVIEW ASSESSMENT OVERVIEW Uncorrected proof, all content subject to change at publisher discretion. Not for resale, circulation or distribution in whole or in part. ©Pearson 2019 The following tables give an overview of the assessment for this course. We recommend that you study this information closely to help ensure that you are fully prepared for this course and know exactly what to expect in the assessment. PAPER 1 SPECIFICATION PERCENTAGE MARK TIME AVAILABILITY Written examination paper Biology 61.1% 110 2 hours January and June Paper code 4BI1/1B and Science Double examination series 4SD0/1B Award First assessment June 2019 Externally set and assessed by Edexcel PAPER 2 SPECIFICATION PERCENTAGE MARK TIME AVAILABILITY Written examination paper Biology 38.9% 70 1 hour 15 mins January and June Paper code 4BI1/2B examination series Externally set and assessed First assessment June 2019 by Edexcel If you are studying Biology then you will take both Papers 1 and 2. If you are studying Science Double Award then you will only need to take Paper 1 (along with Paper 1 for each of the Physics and Chemistry courses). ASSESSMENT OBJECTIVES AND WEIGHTINGS ASSESSMENT OBJECTIVE DESCRIPTION % IN INTERNATIONAL GCSE AO1 Knowledge and understanding of biology 38%–42% AO2 Application of knowledge and 38%–42% understanding, analysis and evaluation of biology AO3 Experimental skills, analysis and 19%–21% evaluation of data and methods in biology F01_EDIB_SB_IGCSE_85084_PRE_i-ix.indd 8 25/04/2017 11:18  ASSESSMENT OVERVIEW ix EXPERIMENTAL SKILLS Uncorrected proof, all content subject to change at publisher discretion. Not for resale, circulation or distribution in whole or in part. ©Pearson 2019 In the assessment of experimental skills, students may be tested on their ability to: solve problems set in a practical context apply scientific knowledge and understanding in questions with a practical context devise and plan investigations, using scientific knowledge and understanding when selecting appropriate techniques demonstrate or describe appropriate experimental and investigative methods, including safe and skilful practical techniques make observations and measurements with appropriate precision, record these methodically and present them in appropriate ways identify independent, dependent and control variables use scientific knowledge and understanding to analyse and interpret data to draw conclusions from experimental activities that are consistent with the evidence communicate the findings from experimental activities, using appropriate technical language, relevant calculations and graphs assess the reliability of an experimental activity evaluate data and methods taking into account factors that affect accuracy and validity. CALCULATORS Students are permitted to take a suitable calculator into the examinations. Calculators with QWERTY keyboards or that can retrieve text or formulae will not be permitted. F01_EDIB_SB_IGCSE_85084_PRE_i-ix.indd 9 25/04/2017 11:18  LIFE PROCESSES 03 THE VARIETY OF LIVING ORGANISMS 25 Uncorrected proof, all content subject to change at publisher discretion. Not for resale, circulation or distribution in whole or in part. ©Pearson 2019 UNIT 1 ORGANISMS AND LIFE PROCESSES All living organisms are composed of microscopic units known as cells. These building blocks of life have a number of features in common, which allow them to grow, reproduce, and generate more organisms. In Chapter 1 we start by looking at the structure and function of cells, and the essential life processes that go on within them. Despite the fact that cells are similar in structure, there are many millions of different species of organisms. Chapter 2 looks at the diversity of living things and how we can classify them into groups on the basis of the features that they show. M01_EDIB_SB_IGCSE_85084_CH01-02_002-037.indd 2 24/04/2017 18:09  ORGANISMS AND LIFE PROCESSES LIFE PROCESSES 3 Uncorrected proof, all content subject to change at publisher discretion. Not for resale, circulation or distribution in whole or in part. ©Pearson 2019 1 LIFE PROCESSES There are structural features that are common to the cells of all living organisms. In this chapter you will find out about these features and look at some of the processes that keep cells alive. LEARNING OBJECTIVES ◼ Understand the characteristics shared by living ◼ Know that ATP provides energy for cells organisms ◼ Know the word equation and balanced chemical ◼ Describe cell structures and their functions, including symbol equation for aerobic respiration the nucleus, cytoplasm, cell membrane, cell wall, mitochondria, chloroplasts, ribosomes and vacuole ◼ Know the word equations for anaerobic respiration ◼ Know the similarities and differences in the structures ◼ Investigate the evolution of carbon dioxide and heat of plant and animal cells from respiring seeds or other suitable living organisms ◼ Understand the role of enzymes as biological catalysts ◼ Understand the processes of diffusion, osmosis and in metabolic reactions active transport by which substances move into and ◼ Understand how temperature changes can affect out of cells enzyme function, including changes to the shape of the ◼ Understand how factors affect the rate of movement of active site substances into and out of cells ◼ Understand how enzyme function can be affected by changes in pH altering the active site ◼ Investigate diffusion in a non-living system (agar jelly) ◼ Investigate how enzyme activity can be affected by BIOLOGY ONLY changes in temperature ◼ Explain the importance of cell differentiation in the BIOLOGY ONLY development of specialised cells ◼ Investigate how enzyme activity can be affected by ◼ Describe the levels of organisation within organisms – changes in pH organelles, cells, tissues, organ systems ◼ Describe the differences between aerobic and BIOLOGY ONLY anaerobic respiration ◼ Understand the advantages and disadvantages of ◼ Understand how the process of respiration produces using stem cells in medicine. ATP in living organisms All living organisms are composed of units called cells. The simplest organisms are made from single cells (Figure 1.1) but more complex plants and animals are composed of millions of cells. In many-celled (multicellular) organisms, there may be hundreds of different types of cells with different structures. They are specialised so that they can carry out particular functions in the animal or plant. Despite all the differences, there are basic features that are the same in all cells. ▲ Figure 1.1 Many simple organisms have ‘bodies’ made from single cells. Here are four examples. M01_EDIB_SB_IGCSE_85084_CH01-02_002-037.indd 3 24/04/2017 18:09  4 ORGANISMS AND LIFE PROCESSES LIFE PROCESSES Uncorrected proof, all content subject to change at publisher discretion. Not for resale, circulation or distribution in whole or in part. ©Pearson 2019 There are eight life processes which take place in most living things. Organisms: ◾◾ require nutrition – plants make their own food, animals eat other organisms ◾◾ respire – release energy from their food ◾◾ excrete – get rid of waste products ◾◾ respond to stimuli – are sensitive to changes in their surroundings ◾◾ move – by the action of muscles in animals, and slow growth movements in plants ◾◾ control their internal conditions – maintain a steady state inside the body ◾◾ reproduce – produce offspring ◾◾ grow and develop – increase in size and complexity, using materials from their food. CELL STRUCTURE This part of the book describes the cell structure of ‘higher’ organisms such as animals, plants and fungi. The cells of bacteria are simpler in structure and will be described in Chapter 2. Most cells contain certain parts such as the nucleus, cytoplasm and cell membrane. Some cells have structures missing, for instance red blood cells are unusual in that they have no nucleus. The first chapter in a biology textbook will usually present diagrams of ‘typical’ plant and animal cells. In fact, there is really no such thing as a ‘typical’ cell. Humans, for example, are composed of hundreds of different kinds of cells – from nerve cells to blood cells, skin cells to liver cells. What we really mean by a ‘typical’ cell is a general diagram that shows all the features that you will find in most cells (Figure 1.2). However, not all these are present in all cells – for example the cells in the parts of a plant that are not green do not contain chloroplasts. animal cell plant cell cell wall nucleus cell membrane (inside cell wall) vacuole cell membrane cytoplasm mitochondria mitochondria cytoplasm