BIOLOGY. BrightRED Study Guide BIOLOGY. Margaret Cook and Fred Thornhill. BrightRED Study Guides. Curriculum for Excellence. Curriculum for Excellence

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1 Curriulum for Exellene Margaret Cook and Fred Thornhill Contains all of the essential ourse information, arranged in easily digestible topis. Don t forget! pointers offer advie on key fats and on how to avoid ommon mistakes. Things to do and think about setions at the end of eah topi allow for further pratie and researh. Worked examples show you how to approah a range of onepts and questions. A glossary of key terms helps you really learn and revise important ourse onepts. htred ur Let Brig ss in yo e u s u to s and lead yo 5 studie l a n o i t Na! beyond THORNHILL Designed in full olour, highly illustrated, aessible and engaging to make sure all that study stiks! COOK This BrightRED Study Guide is just the thing you need to takle your ourse and gain the exam skills essential to sueed at National 5 Biology. Written by trusted authors and experiened Biology teahers Margaret Cook and Fred Thornhill, this book is paked with brilliant examples, tasks and advie. It is the ultimate ompanion to your studies. National 5 National 5 BrightRED W N NE ITIO ED BrightRED Study Guides BrightRED Study Guide Curriulum for Exellene Twie winner of the IPG Eduation Publisher of the Year award. Bright Red Publishing s easy to use, high-quality eduational resoures are trusted by teahers and ustom designed to improve students study experiene to help them to ahieve their potential. To see more of what we do and stay up to date with all things Bright Red: follow us on like us on faebook at Chek out the BrightRED Digital Zone for a world of tests, ativities, links and more at visit us at or all us on we d be delighted to hear from you! -Biology-New Edition-5mm.indd 1 ISBN Don t forget to hek out the BrightRED Digital Zone ED NE IT W IO N BE BRIGHT BE READY 13/11/ :15

2 Introduing National 5 Biology BRIGHTRED STUDY GUIDE: NATIONAL 5 INTRODUCING NATIONAL 5 During this ourse we hope you will develop and apply skills for learning, skills for life and skills for work. Biology is the study of living organisms so it is relevant to everybody. It plays a ruial role in our everyday existene, and is an inreasingly important subjet in the modern world. Advanes in biologial tehnologies have made the subjet more exiting and more relevant than ever. THE NATIONAL 5 COURSE National 5 Biology enourages you to beome: a more onfident learner a responsible itizen with an informed and ethial view of omplex issues, through the study of relevant areas of biology suh as health, environment and sustainability someone who thinks analytially, reatively and independently, and is able to make reasoned evaluations. The National 5 ourse provides opportunities for you to aquire knowledge and skills relevant to urrent biologial topis. The ourse overs major areas of biology, ranging from the study of uniellular organisms to the omplex relationships between organisms in an eosystem. Key areas fous on ells and ellular proesses, leading to an understanding of the importane of ells and their roles. Body systems, reprodution and inheritane are investigated to broaden your understanding of living organisms. The omparison of the proesses in multiellular plants and animals enables you to investigate inreasing levels of omplexity of these organisms. Key areas of biodiversity and interdependene are overed, along with the proesses leading to evolution, and food seurity. COURSE CONTENT You will develop skills of sientifi inquiry, investigation and analytial thinking, along with the required knowledge and understanding. You will also researh issues and ommuniate information related to your findings, developing skills of sientifi literay. Topi 1 Cell biology The key areas overed are: ell struture; transport aross ell membranes; DNA and the prodution of proteins; proteins; geneti engineering; and respiration. Topi 2 Multiellular organisms The key areas overed are: produing new ells; ontrol and ommuniation; reprodution, variation and inheritane; transport systems plants; transport systems animals; and absorption of materials. Topi 3 Life on Earth The key areas overed are: eosystems; distribution of organisms; photo synthesis; energy in eosystems; food prodution; and evolution in speies. The range of skills involved in the ourse are: demonstrating knowledge and understanding of biology by desribing information, explaining and linking knowledge applying biologial knowledge to new situations, interpreting information and solving problems planning, designing and safely arrying out investigations and experiments to test hypotheses or to show partiular effets seleting information from a variety of soures presenting information in a variety of forms proessing information (for example using alulations and units) making preditions and generalisations based on evidene and information justifying onlusions that are supported by evidene suggesting improvements to investigations and experiments ommuniating findings and information. THE EXTERNAL ASSESSMENT At the end of the ourse you will be assessed externally by two omponents. Component 1 Question Paper (80% of total mark) This is made up of a 2½-hour question paper in whih: 25 marks are alloated to an objetive test 75 marks are alloated to the written paper, whih inludes questions requiring a mixture of short (restrited) and extended answers. Many of the marks will be given for applying knowledge and understanding. The other marks will be given for applying sientifi inquiry, analytial thinking and problem solving skills. The question paper will be written and marked by the Sottish Qualifiations Authority (SQA). Component 2 Assignment (20% of total mark) The assignment will be an in-depth study of a biology topi you have hosen. There will be 20 marks awarded for the assignment and the majority of these will be awarded for applying sientifi inquiry and analytial thinking skills. The other marks will be awarded for applying knowledge and understanding relating to the topi. The assignment is arried out under ontrolled onditions and is externally marked by SQA. To prepare for the ontrolled assessment you will hoose, researh and investigate an appropriate topi. Your researh involves gathering data or information from an experiment or fieldwork as well as from the internet or literature. During the assessment you will present evidene of: an aim you have deided upon biologial knowledge and understanding relating to your hosen topi a brief desription of an experiment or fieldwork you have arried out, along with the results data or information from the internet or literature to ompare with your experimental data a reasoned onlusion. This book is supported by the Bright Red Digital Zone. Visit net/biology and disover a world of tests, videos, ativities and more! 4 5

3 Cell Biology Geneti Engineering CELL GENETIC ENGINEERING Have a look at the online debate about the banning of transgeni rops in India at Biology THE TRANSFER OF GENETIC INFORMATION Geneti material an be transferred from one ell to another, either by natural means or artifiially, through the proess of geneti engineering. Sientists have studied the ways in whih viruses transfer their nulei aids into host ells. They found that viruses transferred their geneti material into the host so that it beame attahed to the host s DNA. Researh has shown that some bateria living in the soil are responsible for ausing tumours to develop in plant tissue. Sientists have studied this proess to see how it works. They found that the baterium atually transfers a piee of its own geneti material into the plant root, usually through a wound in the plant tissue. This geneti material is found in one of the baterial plasmids and is responsible for ausing a tumour in the plant root. Through further researh, sientists have developed ways to substitute the genes whih ause tumours with other DNA and they are now able to introdue useful genes into bateria. The bateria then pass these genes into the plant, allowing the plant to be genetially modified in ertain ways. When viruses and bateria transfer their geneti material into ells, these ells are now able to make proteins whih they previously ould not. Sientists saw the potential of this and developed ways of using the tehnique to their advantage. This tehnique has been used to reate transgeni rops (plants with genes from another organism). These rops have advantages over the natural varieties, suh as inreased yields or inreased disease resistane, but ontroversy surrounds their use. GENETIC ENGINEERING The proess of geneti engineering involves taking geneti material from one type of living organism and transferring it into another type of living organism. The organism with the altered geneti make-up is now reprogrammed, or transformed, to make different proteins whih are useful to human beings. Miroorganisms, suh as bateria and yeast, are often reprogrammed to produe useful substanes, inluding mediines and human proteins suh as hormones. There are several advantages to using these single-elled organisms: They grow and multiply very quikly. Being individually small, they are easy to aommodate. They are relatively inexpensive to use. They are easier to reprogramme than more advaned organisms. THE PROCESS OF REPROGRAMMING The arrangement of the hromosomal material in a baterium makes it an ideal organism for geneti engineering. A baterium has one large irular loop of hromosomal material, as well as several muh smaller rings known as plasmids. Plasmids are easily removed from bateria. They are small enough to be removed, genetially altered and put bak into a baterium. The stages involved in the reprogramming of bateria to produe a human protein, suh as insulin, are as follows: 1 The setion of DNA in the human ell that has the required gene, is identified on its original hromosome. 2 The gene is ut out of the hromosome using an enzyme. 3 A plasmid is removed from a baterium. 4 The plasmid is ut open using the same enzyme. 5 The required gene is inserted into the plasmid using another type of enzyme. 6 This is repeated many times. 7 The altered plasmids are then inserted into bateria. 8 The reprogrammed bateria are given the orret onditions to reprodue, making many idential opies. The bateria that have been genetially modified (GM bateria) with the transferred gene make large quantities of the gene s protein, if given suitable onditions. human ell 1 human hromosome isolated and gene seleted 2 enzymes used to ut out the seleted gene 7 pulses of eletriity punh holes in the baterial ell wall, allowing plasmid to enter One of the important advantages Geneti engineering of bateria of using bateria in this way is the rapid rate at whih they reprodue. This means that the mass prodution of the desired protein using this method is a relatively quik proess. Cytoplasm Cell membrane Plasmid Loop of hromosomal material 5, 6 human gene inserted and plasmid sealed using enzymes human protein extrated and purified 3 DNA plasmid removed 8 baterium multiplies to produe lones baterium 4 enzymes used to ut open plasmid Geneti information an be transferred from one ell to another by geneti engineering. Enzymes are used in several stages in the proess of geneti engineering. Can you explain why the same enzyme an be used to ut the required gene from the human hromosome and to ut open the plasmid, but a different enzyme is required to put the gene into the plasmid? Test yourself on the transfer of geneti information online at Biology 20 21

4 Multiellular Organisms Variation and Inheritane 1 MULTICELLULAR ORGANISMS VARIATION AND INHERITANCE 1 Shape of aspen leaves Pattern of one shells AN INTRODUCTION TO VARIATION The members of a speies are not idential, even though they all possess geneti information for the same range of harateristis. Individuals show variations whih make them different from one another. Some variations may be due to effets of the environment whih influene the development of an individual. These variations are unimportant to the speies as a whole beause they are not passed on from parent to offspring. Other variations are aused by differenes in the geneti information of individuals and these an be inherited. Sexual reprodution involves ombining geneti information from both parents. This allows mixing of genes in different ways and so ontributes to variation. The photographs show some examples of variation between members of the same speies. Genes an exist in different forms, eah apable of produing a variant of a partiular harateristi. The different forms of a gene are alled alleles. DISCRETE VARIATION Disrete variation of a harateristi shows only a limited number of distint possibilities. This type of variation is found in harateristis that are oded by a single gene with a limited number of forms or alleles. Disrete variation has been important in the study of inheritane. Charateristis whih have easily reognised variants are observed in suessive generations. The patterns of their inheritane have allowed researhers to work out the mehanism involved. Examples of disrete variation inlude: CONTINUOUS VARIATION Continuous variation of a harateristi shows a ontinuous range of possibilities between a minimum and a maximum value. There are no distint groups and an individual s harateristi may have a value anywhere in the overall range of possibilities. Continuous variation ours beause several different genes influene the same harateristi. Suh a harateristi is said to be polygeni. When a number of genes ontribute to a harateristi, it means that there are many different ombinations of the various alleles involved. This produes many possible values for that harateristi, forming a ontinuous range of possibilities. Examples of ontinuous variation inlude height, weight and hand span. Most visible harateristis are polygeni. It is probable that even some of those harateristis whih show disrete variation and that are explained by single gene inheritane are influened by more than one gene. When the values for a polygeni harateristi are olleted for a large number of individuals, it is found that they always show the same pattern of distribution. Relatively few individuals show values lose to the extremes of the range. Most individuals show values lose to the middle of the range, in other words a value lose to the average. This type of distribution is alled a normal distribution. When it is plotted as a graph or hart, it shows a typial bell-shaped urve. The photograph below shows a small group of people, all from the same university department, standing in order of their heights (in feet and inhes). The graph whih follows it shows the distribution of their heights (in entimetres). The distribution is not a perfet normal distribution but the dotted line shows the overall pattern. If the sample size had been greater (more people inluded) then we would expet the pattern of height distribution to be loser to the typial normal distribution. Chek how well you ve learned about variation online at www. brightredbooks.net/ Biology The prodution of haploid gametes from diploid body ells and the random ombination of gametes at fertilisation both ontribute to geneti variation. Human faes at hair length tongue-rolling ability. A) short hair B) long hair Number of people Height (m) The distribution of heights in a group of people A) Tongue-rolling ability B) Non-tongue rolling ability blood groups There are four possible blood groups. These are: 1 Group A 2 Group B 3 Group AB 4 Group O 1 What is the most ommon height of the people in the group? 2 Can you alulate their average height to the nearest entimetre? 56 57

5 Life on Earth Eosystems 2 LIFE ON EARTH ECOSYSTEMS 2 EFFECTS OF THE LOSS OF ORGANISMS FROM A FOOD WEB FOOD WEBS In reality, the transfer of energy in an eosystem is not as simple as it appears in a food hain. This is beause most organisms have more than one food soure and any one type of organism may be eaten by a range of predators. Therefore, most food hains are interlinked into more ompliated systems alled food webs. For example, part of a food web involving the organisms from the food hain is shown below. A food web If the beaver population fell beause of a fatal disease, then a major food soure of eagles and wolves would be lost. With hares then being the only food soure for the eagles and wolves, the population of hares would soon beome too small to support the eagles and wolves. Therefore the whole food web would have ollapsed. Snakes Spiders Seed-eating Birds Eagle Grey wolf Toads Red squirrel Mie Snowshoe hare Moose Beaver Wath the video at www. brightredbooks.net to learn more about eosystems. Predaeous Insets Plant-eating inset Pine Tree Maple Tree Fir Tree Aspen Aquati plants In this ase, the loss of the beavers would not have suh a atastrophi effet beause the eagles and wolves still have several other food soures available. The extra demand plaed on these other food soures would ause some flutuations in numbers but in time a new balane would be ahieved amongst the remaining populations. Plants Test yourself on Eosystems at Biology Aspen Compare this situation to the more omplex food web below. Blakbirds Squirrels Beaver The greater the omplexity or biodiversity of a food web, the more stable it is likely to be. This means that it will be able to adapt to hanges aused by the loss of some organisms. Red fox Rabbits Grey wolf Consider the Canadian food web on the right: Hawks and owls Foxes Food webs an be affeted by hanges in the population of any of the Eagle organisms whih are part of it. For example, in the food web on page 76, if the aphid population was to fall then there would be a derease in the number of spiders and predaeous insets. This would ause a derease in the blakbird and toad populations whih, in turn, would affet the populations of foxes, hawks and owls, and snakes. There would be further onsequenes for the populations of rabbits, squirrels, mie and seed-eating birds. Snowshoe hare A desription of the position that an organism oupies in a food web is very lose to a desription of its nihe. From the food web on page 76: It is possible to find many individual food hains in a food web suh as this. (a) name all the herbivores The greater the biodiversity (number of different speies present) in a food web, the greater is its ability to adapt to hanges aused by the loss of one speies. (b) name all the omnivores () name all the arnivores (d) name all the animals whih are both predator and prey

6 Curriulum for Exellene Margaret Cook and Fred Thornhill Contains all of the essential ourse information, arranged in easily digestible topis. Don t forget! pointers offer advie on key fats and on how to avoid ommon mistakes. Things to do and think about setions at the end of eah topi allow for further pratie and researh. Worked examples show you how to approah a range of onepts and questions. A glossary of key terms helps you really learn and revise important ourse onepts. htred ur Let Brig ss in yo e u s u to s and lead yo 5 studie l a n o i t Na! beyond THORNHILL Designed in full olour, highly illustrated, aessible and engaging to make sure all that study stiks! COOK This BrightRED Study Guide is just the thing you need to takle your ourse and gain the exam skills essential to sueed at National 5 Biology. Written by trusted authors and experiened Biology teahers Margaret Cook and Fred Thornhill, this book is paked with brilliant examples, tasks and advie. It is the ultimate ompanion to your studies. National 5 National 5 BrightRED W N NE ITIO ED BrightRED Study Guides BrightRED Study Guide Curriulum for Exellene Twie winner of the IPG Eduation Publisher of the Year award. Bright Red Publishing s easy to use, high-quality eduational resoures are trusted by teahers and ustom designed to improve students study experiene to help them to ahieve their potential. To see more of what we do and stay up to date with all things Bright Red: follow us on like us on faebook at Chek out the BrightRED Digital Zone for a world of tests, ativities, links and more at visit us at or all us on we d be delighted to hear from you! -Biology-New Edition-5mm.indd 1 ISBN Don t forget to hek out the BrightRED Digital Zone ED NE IT W IO N BE BRIGHT BE READY 13/11/ :15