IB Biology Study Guide: 2014 edition (Oxford IB Study Guides) PDF
Preview IB Biology Study Guide: 2014 edition (Oxford IB Study Guides)
O X F O R D I B S T U D Y G U I D E S Andrew Allott B i o lo g y FO R TH E I B D I PLO M A 2014 edition 2 3 Great Clarendon Street, Oxford, OX2 6DP, United Kingdom Oxford University Press is a department of the University of Oxford. It furthers the Universitys objective of excellence in research, scholarship, and education by publishing worldwide. Oxford is a registered trade mark of Oxford University Press in the UK and in certain other countries Oxford University Press 2014 The moral rights of the authors have been asserted First published in 2014 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, without the prior permission in writing of Oxford University Press, or as expressly permitted by law, by licence or under terms agreed with the appropriate reprographics rights organization. Enquiries concerning reproduction outside the scope of the above should be sent to the Rights Department, Oxford University Press, at the address above. You must not circulate this work in any other form and you must impose this same condition on any acquirer British Library Cataloguing in Publication Data Data available 978-0-19-839351-1 10 9 8 7 6 5 4 3 2 1 Paper used in the production of this book is a natural, recyclable product made from wood grown in sustainable forests. The manufacturing process conforms to the environmental regulations of the country of origin. Printed in Great Britain Acknowledgements The publishers would like to thank the following for permissions to use their photographs: Artwork by OUP and Six Red Marbles Cover image: Martin Harvey / Alamy p1: http://www.ncbi. SCIENCE PHOTO LIBRARY; p11: OUP; p11: Public Domain; nlm.nih.gov; p1: OUP; p1:CreativeNature.nl/Shutterstock; p11: Dennis Degnan/CORBIS; p12: Public Domain; p12: p1: Public Domain p1: Public Domain; p1: Nigel Cattlin/ STEVE GSCHMEISSNER/SCIENCE PHOTO LIBRARY; p13: DAVID Visuals Unlimited/Corbis; p1: OUP; p1: OUP; p1: ZEPHYR/ PARKER/SCIENCE PHOTO LIBRARY; p15: OUP; p17: staticd/ SCIENCE PHOTO LIBRARY; p2: OUP; p2: Public Domain; p2: Wikipedia; p16: OUP; p16: M.I. WALKER/SCIENCE PHOTO PR. PHILIPPE VAGO, ISM/SCIENCE PHOTO LIBRARY; p2: Public LIBRARY; p16: SCIENCE PICTURES LTD/SCIENCE PHOTO Domain; p2: Public Domain; p2: DR KEITH WHEELER/SCIENCE LIBRARY; p71: OUP; p71: OUP; p71: OUP; p71: OUP; p71: PHOTO LIBRARY; p2: OUP; p2: OUP; p2: Public Domain; OUP; p71: OUP; p87: DR KEITH WHEELER/SCIENCE PHOTO p3: SCI-COMM STUDIOS/SCIENCE PHOTO LIBRARY; p3: DR LIBRARY; p100: OUP; p121: DR KEITH WHEELER/SCIENCE JEREMY BURGESS/SCIENCE PHOTO LIBRARY; p3: OUP; p3: DR PHOTO LIBRARY; p128: OUP; p128: OUP; p128: OUP; p145: KEITH WHEELER/SCIENCE PHOTO LIBRARY; p3: BIOPHOTO OUP; p145: DR P. MARAZZI/SCIENCE PHOTO LIBRARY; p145: ASSOCIATES/SCIENCE PHOTO LIBRARY; p3: DR KEITH Sam Droege/Flickr; p165: Public Domain; p183: SUSUMU WHEELER/SCIENCE PHOTO LIBRARY; p3: NATIONAL LIBRARY NISHINAGA/SCIENCE PHOTO LIBRARY. OF MEDICINE/SCIENCE PHOTO LIBRARY; p3: Bettmann/ Although we have made every effort to trace and contact all CORBIS; p3: OUP; p3: BIOPHOTO ASSOCIATES/SCIENCE PHOTO copyright holders before publication this has not been possible LIBRARY; p3: MICROSCAPE/SCIENCE PHOTO LIBRARY; p4: in all cases. If notied, the publisher will rectify any errors or http://myibsource.com; p4: Dr Graham Beards/Wikipedia; p4: omissions at the earliest opportunity. DR DAVID FURNESS, KEELE UNIVERSITY/SCIENCE PHOTO LIBRARY; p4: ASTRID & HANNS-FRIEDER MICHLER/SCIENCE Any third party use of this publication is prohibited. Interested PHOTO LIBRARY; p4: Michael Abbey/SCIENCE PHOTO LIBRARY; parties should apply to the copyright holders indicated in each p5: OUP; p5: The American Association for the Advancement case. of Science; p5: OUP; p5: OUP; p5: THOMAS DEERINCK, NCMIR/ SCIENCE PHOTO LIBRARY; p6: MOREDUN ANIMAL HEALTH LTD/SCIENCE PHOTO LIBRARY; p6: OUP; p6: Jmol; p6: Jmol; p6: Jmol; p6: Public Domain; p6: OUP; p6: http://www3. nd.edu; p6: Dr. Michal Laurent, KULeuven, Belgium; p7: OUP; p8: OUP; p8: OUP; p8: Public Domain; p8: Dr. Gladden Willis/ Getty Images; p8: Image Source/Getty Images; p9: OUP; p9: OUP; p9: OUP; p9: Public Domain; p10: MEDICAL SCHOOL, UNIVERSITY OF NEWCASTLE UPON TYNE/SIMON FRASER/ Introduction and acknowledgements th IB Biy P h b phivy vi i y vp hiq i bfi y, b hi spb 2014 . thi b h b h h h h i i p h i vi i i ii y. a hh i h piip hp f h ii h hy qiy biy i i i h h iy h yi h p. h h ppii. Biy h a pi i Hih lv (Hl) s lv (sl) Biy i h i b h v, ii pi. th pi v i hy i pi hi i. th IB h q i h yb, b ihi pi Biy ii h p h q b-pi h b ihy , iv ii i. th y ppii h pi i. hi i Biy. ap h, ivi i iz i i. livi i hh tpi 16 pi i bh Hl sl. h biph, ii h, ip. tpi 711 ii pi i y Hl. H ivii hv ii ip, ii opi ad b i Hl sl, ih x i pi i i p h biph i Hl, p y p h -h biiviy. h pi. P h h p, y I vy h hp h h hv iv pi i i. i h ii hi b. e w ox Pi qi i h pi pi. uiviy P hp, Ji th a h qi iv, hh i hi py i. I ib y i ai h y b b f h vi ! wii hi pp b i h gi i iv i i y h h I hv p i. I i i ppi f x. h h I i h b bii h , h ivi v ivi i th h v b ip xii i hi hbi. y biy. th p ppii IntroductIon and acknowledgements iii Contents 1 cell BIologY Autosomal genetic diseases 43 Cell theory 1 Sex-linkage 44 Unicellular and multicellular organisms 2 Co-dominance 45 Stem cells 3 Mutation 46 Light microscopes and drawing skills 4 Genes and alleles 47 Electron microscopes and ultrastructure 5 Gene sequencing 48 Prokaryotic cells 6 DNA technology 49 Eukaryotic cells 7 DNA proling 50 Models o membrane structure 8 Genetic modication 51 Membrane structure 9 Cloning 52 Diusion and acilitated diusion 10 Questions genetics 53 4 ecologY Osmosis 11 Active transport 12 Modes o nutrition 54 Origins o cells 13 Communities and ecosystems 55 Mitosis 14 Energy fow 56 Cell cycles and cancer 15 Food chains and energy pyramids 57 Questions cell biology 16 Nutrient cycles 58 2 molecular BIologY Carbon cycle 59 Molecules to metabolism 17 Global warming and the greenhouse eect 60 Water 18 Rising carbon dioxide concentrations 61 Water and lie 19 Questions ecology 62 5 eVolutIon and BIodIVersItY Carbohydrates 20 Molecular visualization o polysaccharides 21 Introducing evolution 63 Lipids 22 Further evidence or evolution 64 Lipids and health 23 Natural selection 65 Amino acids and polypeptides 24 Natural selection in action 66 Protein structure and unction 25 Naming and identiying 67 Enzymes 26 Classication o biodiversity 68 Factors aecting enzyme activity 27 Classication o eukaryotes 69 Structure o DNA and RNA 28 Cladistics 70 DNA replication 29 Questions evolution and biodiversity 71 Transcription and translation 30 6 Human PHYsIologY The genetic code 31 Digestion 72 Cell respiration 32 Absorption 73 Respirometers 33 The cardiovascular system 74 Photosynthesis 34 The heart 75 Investigating limiting actors 35 Deence against inectious disease 76 Chromatography 36 Antibodies and antibiotics 77 Questions molecular biology 37 Ventilation 78 3 genetIcs Gas exchange 79 Chromosomes 38 Neurons and synapses 80 Karyograms 39 Nerve impulses 81 Meiosis 40 Regulating blood glucose and body temperature 82 Meiosis and genetic variation 41 Leptin and melatonin 83 Principles o inheritance 42 Reproductive systems 84 iv contents Conception and pregnancy 85 Chi-squared and continuous variation 126 Research into reproduction 86 Speciation 127 Questions human physiology 87 Questions genetics and evolution 128 7 nucleIc acIds 11 anImal PHYsIologY Landmarks in DNA research 88 Antigens and allergy 129 DNA replication 89 Antibody production 130 Base sequences in DNA 90 Vaccination and monoclonal antibodies 131 Bioinormatics and nucleosomes 91 Muscle 132 Gene expression 92 Muscle contraction 133 Epigenetics 93 Movement 134 Ribosomes and transer RNA 94 Excretion and osmoregulation 135 Translation 95 Kidney structure and ultraltration 136 Primary and secondary structure o proteins 96 Urine production and osmoregulation 137 Tertiary and quaternary structure o proteins 97 Kidney unction and kidney ailure 138 Questions nucleic acids 98 Excretion and osmoregulation in animals 139 8 metaBolIsm, cell resPIratIon Spermatogenesis 140 and PHotosYntHesIs Oogenesis 141 Fertilization 142 Enzymes and activation energy 99 Pregnancy and childbirth 143 Enzyme inhibition 100 Structure and unction o the placenta 144 Controlling metabolic pathways 101 Questions animal physiology 145 Glycolysis 102 a neuroBIologY and BeHaVIour Krebs cycle 103 ATP production by oxidative phosphorylation 104 Neurulation 146 Mitochondria 105 Development o the nervous system 147 Light-dependent reactions o photosynthesis 106 Functions o the brain 148 Chloroplast structure 107 Cerebral hemispheres 149 Light-independent reactions o photosynthesis 108 Perception o stimuli 150 Calvins experiments 109 Vision in humans 151 Questions metabolism, cell respiration and Hearing in humans 152 photosynthesis 110 Innate behaviour (HL only) 153 9 Plant BIologY Learned behaviour (HL) 154 Transpiration 111 Neurotransmitters and synapses (HL only) 155 Investigating transpiration 112 Ethology (HL only) 156 Water uptake and water conservation 113 Questions neurobiology and behaviour 157 B BIotecHnologY and InFormatIcs Vascular tissue in plants 114 Water transport in xylem 115 Microorganisms and ermenters 158 Phloem transport 116 Microorganisms in industry 159 Research in plant physiology 117 Genetic modication o crop plants 160 Plant hormones and growth o the shoot 118 Bioremediation 161 Reproduction in fowering plants 119 Biotechnology in diagnosis (HL only) 162 Propagating plants 120 Biotechnology in therapy (HL only) 163 Questions plant biology 121 Bioinormatics (HL only) 164 10 genetIcs and eVolutIon Questions biotechnology and bioinormatics 165 c ecologY and conserVatIon Mendels law o independent assortment 122 Dihybrid crosses 123 Community structure 166 Genes linked and unlinked 124 Interactions and energy fow 167 Crossing-over 125 Nutrient cycles and change in ecosystems 168 contents v Impacts o humans on ecosstems 169 Cardiolog 179 Biodiversit and conservation 170 Endocrine glands and hormones (HL onl) 180 Populations (HL onl) 171 Carbon dioide transport (HL onl) 181 Nitrogen and phosphorus ccles (HL onl) 172 Ogen transport (HL onl) 182 Questions ecolog and conservation 173 Questions human phsiolog 183 d Human PHYsIologY Human nutrition 174 ExAM ADVICE 184 Defcienc diseases and diseases o the gut 175 NATURE OF SCIENCE A SUMMARy 186 Digestion and absorption 176 ADVICE FOR INTERNAL ASSESSMENT (IA) 188 Liver 177 ANSWERS TO QUESTIONS 189 Cardiac ccle 178 INDEx 196 vi contents 1 C E LL B I O LO G Y Cell theory INTRODUCING THE CELL THEORY One the most important theories in biology is that cells are the o indivisible subunits, but the invention o the microscope smallest possible units o lie and that living organisms are settled this debate. Cells consist o cytoplasm, enclosed in a made o cells. The ancient Greeks had debated whether living plasma membrane. In plant and animal cells there is usually a organisms were composed o an endlessly divisible uid or nucleus that contains genes. Human cheek cell Moss leaf cell cytoplasm chloroplasts plasma membrane cell wall nucleus plasma cytoplasm membrane nucleus mitochondria sap in vacuole vacuole membrane EXCEPTIONS TO THE CELL THEORY DRAWINGS IN BIOLOGY The cell theory was developed because biologists observed The command term draw is defned by IB as: Represent a trend or living organisms to be composed o cells. Scientifc by means of a labelled, accurate diagram or graph, using theories can be tested by looking or discrepancies cases a pencil. A ruler (straight edge) should be used for straight that do not ft the theory. There are some tissues and lines. Diagrams should be drawn to scale. organisms that are not made o typical cells: A sharp pencil with a hard lead (2H) should be used. This allows 1. Skeletal muscle is made up o muscle fbres. Like cells clear, sharp single lines to be drawn. In exams, diagrams should these fbres are enclosed inside a membrane, but they not be drawn aintly as they will not show clearly in scans. are much larger than most cells (300 or more mm long) and contain hundreds o nuclei. 2. Giant algae such as Acetabularia (below) can grow to a length o as much as 100mm so we would expect them to consist o many small cells but they only contain a single nucleus so are not multicellular. bad good There should be no gaps, overlaps or multiple lines. cytoplasm bad good Labelling can be in ink or pencil, with labelling lines rather 20 mm than arrows. Labelling lines should be drawn using a ruler and they should point precisely to the structure being labelled. nucleus 3. Aseptate fungi consist o thread-like structures called hyphae. These hyphae are not divided up into sub-units containing a single nucleus. Instead there are long undivided sections o hypha which contain many nuclei. cell cell Despite these and some other discrepancies, there is still a bad good strong overall trend or living organisms to be composed o cells, so the cell theory has not been abandoned. CELL BIOLOGY 1 Unicellular and multicellular organisms FUNCTIONS OF LIFE IN UNICELLULAR ORGANISMS Unicellular organisms consist o only one cell. They carry out all unctions o cilia lie in that cell. Two examples are given agellum here: Paramecium lives in ponds and contractile vacuole is between a twentieth and a third o a eye spot millimetre long. Chlamydomonas lives in plasma membrane reshwater habitats and is between 0.002 nucleus cell wall and 0.010 millimetres in diameter. They cytoplasm chloroplast are similar in how they carry out some unctions o lie and dierent in others. food in vesicles Paramecium Chlamydomonas Function Paramecium Chlamydomonas Nutrition Feeds on smaller organisms by ingesting and Produces its own ood by photosynthesis using a digesting them in vesicles (endocytosis) chloroplast that occupies much o the cell Growth Increases in size and dry mass by accumulating Increases in size and dry mass due to organic matter and minerals rom its ood photosynthesis and absorption o minerals Response Reacts to stimuli, e.g. reverses its direction o Reacts to stimuli, e.g. senses where the brightest movement when it touches a solid object light is with its eyespot and swims towards it Excretion Expels waste products o metabolism, e.g. CO Expels waste products o metabolism, e.g. oxygen 2 rom respiration difuses out o the cell rom photosynthesis difuses out o the cell Metabolism Both: produces enzymes which catalyse many diferent chemical reactions in the cytoplasm Homeostasis Both: keeps internal conditions within limits, e.g. expels excess water using contractile vacuoles Reproduction Both: reproduces asexually using mitosis or sexually using meiosis and gametes MULTICELLULAR ORGANISMS DIFFERENTIATION As a cell grows larger its surace area to volume ratio An organisms entire set o genes is its genome. In a becomes smaller. The rate at which materials enter or leave multicellular organism each cell has the ull genome, so it a cell depends on the surace area o the cell. However, the has the instructions to develop into any type o cell. During rate at which materials are used or produced depends on the diferentiation a cell uses only the genes that it needs to ollow volume. A cell that becomes too large may not be able to take its pathway o development. Other genes are unused. For in essential materials or excrete waste substances quickly example, the genes or making hemoglobin are only expressed enough. Large organisms are thereore multicellular they in developing red blood cells. Once a pathway o development consist o many cells. has begun in a cell, it is usually xed and the cell cannot change Being multicellular has another advantage. It allows to a diferent pathway. The cell is said to be committed. division o labour diferent groups o cells (tissues) Heart muscle tissue become specialized or diferent unctions by the process 20 m o diferentiation. The drawings (right) show two o the hundreds o types o diferentiated cell in humans. EMERGENT PROPERTIES Emergent properties arise rom the interaction o the Pancreatic islet cell component parts o a complex structure. We sometimes sum this up with the phrase: the whole is greater than the sum o its parts. Multicellular organisms have properties that emerge rom the interaction o their cellular components. For example, each cell in a tiger is a unit o lie that has distinctive properties such as sensitivity to light in retina cells, but all o a tigers cells combined give additional 4000 emergent properties or example the tiger can hunt and kill and have a proound ecological efect on its ecosystem. vesicles of insulin 2 CELL BIOLOGY Stem cells STEM CELLS ETHICS OF THERAPEUTIC USE OF Stem cells are dened as cells that have the capacity to divide STEM CELLS and to diferentiate along diferent pathways. Human embryos Ethics are moral principles that allow us to decide consist entirely o stem cells in their early stages, but gradually whether something is morally right or wrong. Scientists the cells in the embryo commit themselves to a pattern o should always consider the ethics o research and its diferentiation. Once committed, a cell may still divide several consequences beore doing it. more times, but all o the cells ormed will diferentiate in the The main argument in avour o therapeutic use o stem cells same way and so they are no longer stem cells. is that the health and quality o lie o patients sufering rom Small numbers o cells persist as stem cells and are still otherwise incurable conditions may be greatly improved. present in the adult body. They are ound in most human Ethical arguments against stem cell therapies depend on the tissues, including bone marrow, skin and liver. They give source o the stem cells. There are ew objections to the use some human tissues considerable powers o regeneration o an adults own stem cells or cells rom an adult volunteer. and repair, though they do not have as great a capacity to Newborn babies cannot give inormed consent or stem cells to diferentiate in diferent ways as embryonic stem cells. be harvested rom their umbilical cord, but parental consent is Other tissues lack the stem cells needed or efective given and the cells are stored in case they are needed during repair brain, kidney and heart, or example. There has the babys subsequent lie, which seems unobjectionable. been great interest in the therapeutic use o embryonic stem However, the ethical issues concerning stem cells taken rom cells with organs such as these. There is great potential or specially created embryos are more controversial. Some argue the use o embryonic stem cells or tissue repair and or that an embryo is a human lie even at the earliest stage and treating a variety o degenerative conditions, or example i the embryo dies as a result o the procedure it is immoral, Parkinsons disease. because a lie has been ended and benets rom therapies using embryonic stem cells do not justiy the taking o a lie. There are a several counter-arguments: earlystageembryosarelittlemorethanballsofcellsthat have yet to develop the essential eatures o a human lie earlystageembryoslackanervoussystemsodonotfeel pain or sufer in other ways during stem cell procedures ifembryosareproduceddeliberately, no individual that would otherwise have had the chance o living is denied the chance o lie largenumbersofembryosproducedbyIVFarenever implanted and do not get the chance o lie; rather than kill these embryos it is better to use stem cells rom them Removing a stem cell rom an embryo to treat diseases and save lives. EXAMPLES OF THERAPEUTIC STEM CELL USE 1. Stargardts macular dystrophy is a genetic disease that 2. Leukemia is a type o cancer in which abnormally develops in children between the ages o 6 and 12. Most large numbers o white blood cells are produced in the cases are due to a recessive mutation o a gene called bone marrow. A normal adult white blood cell count ABCA4. This causes a membrane protein used or active is 4,00011,000 per mm3 o blood. With leukemia the transport in retina cells to malunction, so photoreceptive count rises above 30,000 and with acute leukemia above cells degenerate and vision becomes progressively worse. 100,000 per mm3. The loss o vision can be severe enough or the person to Adult stem cells are used in the treatment o leukemia: be registered as blind. A large needle is inserted into a large bone, usually the Researchers have developed methods or making pelvis and uid is removed rom the bone marrow. embryonic stem cells develop into retina cells. This was Stem cells are extracted rom this uid and are stored by done initially with mouse cells but, in 2010, a woman in reezing them. They are adult stem cells and only have the her 50s with Stargardts disease was treated by having potential or producing blood cells. 50,000 retina cells derived rom embryonic stem cells A high dose o chemotherapy drugs is given to the patient, injected into her eyes. The cells attached to the retina to kill all the cancer cells in the bone marrow. The bone and remained there during the our-month trial. There was marrow loses its ability to produce blood cells. an improvement in the womans vision, and no harmul side efects. Further trials with larger numbers o patients The stem cells are then returned to the patients body. They are needed, but ater these initial trials at least, we can re-establish themselves in the bone marrow, multiply and be optimistic about the development o treatments or start to produce red and white blood cells. In many cases Stargardts disease using embryonic stem cells. this procedure cures the leukemia completely. CELL BIOLOGY 3 Light microscopes and drawing skills USING LIGHT MICROSCOPES MAGNIFICATION CALCULATIONS 1. Treat the specimen with a stain that makes parts o the Microscopes are used to investigate the structure o cells and cells o the specimen visible. tissues. Most microscopes use light to orm an image and can 2. Mount the specimen on a microscope slide with a cover make structures appear up to 400 times larger than their actual slip to make it at and protect the microscope. size. Electron microscopes give much higher magnications. 3. Put the microscope slide on the stage so the specimen is The structures seen with a microscope can be recorded below the objective lens. with a neat drawing or a photograph can be taken down the microscope called a micrograph. An important skill 4. Plug in the microscope and switch on the power so that in biology is calculating the magnication o a drawing or light passes through the specimen. micrograph. Use these instructions: 5. Focus with the low power objective lens rst. 1. Choose an obvious length, or example the maximum 6. Use the ocusing knobs to bring the slide and objective diameter o a cell. Measure it on the drawing. lens as close as possible without touching. 2. Measure the same length on the actual specimen. 7. Look through the eyepiece lens and move the slide and 3. I the units used or the two measurements are diferent, objective lens apart with the coarse ocusing knob until convert them into the same units. the specimen comes into ocus. One millimetre (mm) = 1,000 micrometres (m) 8. Use the ne ocusing knob to ocus on particular parts o the specimen. 4. Divide the length on the drawing by the length on the actual specimen. The result is the magnifcation. 9. Move the slide to bring the most interesting part o the _siz_e o _imag_e specimen into the centre o the eld o view. Magnication = size o specimen 10. Turn the revolving nose piece to select the high power Example objective, then reocus using steps 57 again. The scale bar on the drawing o heart muscle tissue on 11. Adjust the illumination using the diaphragm. page 2 represents a length on the specimen o 20 m and is 10 mm long, which is 10,000 m. eye piece _10,0_00 Magnication = = 500 20 The magnication equation can be rearranged and used to nose piece calculate the actual size o a specimen i the magnication objective lens and size o the image are known. stage _size _o im_age coarse focusing Size o specimen = magnication condenser lens knob Example and diaphragm ne focusing knob The length o the beta cell in the pancreatic islet on page 2 is 48mm, which is 48,000 m, and the magnication o the drawing is 4000. lamp _48,0_00 _m Actual length o the cell = = 12 m 4000 SCALE BARS A scale bar is a line added to a micrograph or a drawing to help to show the actual size o the structures. For example, a 10 m bar shows how large a 10 m object would appear. The gure below is a scanning electron micrograph (SEM) o a lea with the magnication and a scale bar both shown. 50 m S.I. size units 1000mm = 1 m 1000m = 1nm 1000nm = 1m Scanning electron micrograph o lea (x480) 4 CELL BIOLOGY
The list of books you might like
