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Wellsway school science dept. Curriculum 2011 – AQA Science -1- Biology workbook Wellsway school science dept. Curriculum 2011 – AQA Science Biology workbook Why individuals of the same species are different from each other, and the new methods we have for producing plants and animals with the characteristics we prefer. There are not only differences between different species of plants and animals but also between individuals of the same species. These differences are due partly to the information in the cells they have inherited from their parents and partly to the different environments in which the individuals live and grow. Asexual reproduction can be used to produce individuals exactly like their parents. Scientists can now add, remove or change genes to produce the plants and animals they want. Candidates should use their skills, knowledge and understanding to: interpret information about cloning techniques and genetic engineering techniques make informed judgements about the economic, social and ethical issues concerning cloning and genetic engineering, including GM crops. Subject content - Why organisms are different. a) The information that results in plants and animals having similar characteristics to their parents is carried by genes which are passed on in the sex cells (gametes) from which the offspring develop. b) The nucleus of a cell contains chromosomes. Chromosomes carry genes that control the characteristics of the body. c) Different genes control the development of different characteristics of an organism. d) Differences in the characteristics of different individuals of the same kind may be due to differences in: • the genes they have inherited (genetic causes) • the conditions in which they have developed (environmental causes) or a combination of both. Reproduction a) There are two forms of reproduction: • sexual reproduction – the joining (fusion) of male and females gametes. The mixture of the genetic information from two parents leads to variety in the offspring • asexual reproduction – no fusion of gametes and only one individual is needed as the parent. There is no mixing of genetic information and so no variation in the offspring. These genetically identical individuals are known as clones. b) New plants can be produced quickly and cheaply by taking cuttings from older plants. These new plants are genetically identical to the parent plant. c) Modern cloning techniques include: • tissue culture – using small groups of cells from part of a plant • embryo transplants – splitting apart cells from a developing animal embryo before they become specialised, then transplanting the identical embryos into host mothers • adult cell cloning. d) In genetic engineering, genes from the chromosomes of humans and other organisms can be „cut out‟ using enzymes and transferred to cells of other organisms. e) Genes can also be transferred to the cells of animals, plants or microorganisms at an early stage in their development so that they develop with desired characteristics. 1. Revise with your teacher the basic structure and functions of animal and plant cells. Label the diagrams overleaf. -2- Wellsway school science dept. Curriculum 2011 – AQA Science ANIMAL CELL 2. Biology workbook PLANT CELL What is the function of the nucleus in: a. plant cells b. animal cells 3 Discuss with your teacher the relationship between the nucleus, chromosomes, genes and DNA. Using labelled diagrams show this relationship in the space below & overleaf. -3- Wellsway school science dept. Curriculum 2011 – AQA Science Biology workbook If you have finished…. find out how DNA’s genetic code leads to the production of an organisms inherited characteristics. 4. Comparing sexual & asexual reproduction. Read your textbook or support material on sexual & asexual reproduction. Explain briefly each of the following terms: a. gamete b. fertilisation c. embryo d. genetic variation -4- Wellsway school science dept. Curriculum 2011 – AQA Science e. meiosis f. mitosis g. genetically identical h. clone i. mutation j. characteristic k. Ionising radiation l. Mutagenic. -5- Biology workbook Wellsway school science dept. 5. Curriculum 2011 – AQA Science Biology workbook Complete the table comparing the features of sexual & asexual reproduction. Feature Sexual reproduction Asexual Reproduction Number of parents Are sex cells produced? Does fertilisation take place? Type of cell division Genes in offspring Variation in offspring Advantages Disadvantage Examples -6- Wellsway school science dept. 6. Curriculum 2011 – AQA Science Biology workbook Watch the video, MSS presentation or PowerPoint on asexual reproduction & cloning. Read your textbook or support material on asexual reproduction & cloning. Discuss with your teacher the meaning of the terms: asexual reproduction, and cloning. Revise mitosis, to remind yourself about how clones are produced. Answer the questions below: (a) Define the term asexual reproduction: (b) Define the term “cloning”: (c) Farmers & gardeners have been “cloning” for many centuries. Give 3 examples of traditional cloning techniques: (i) (ii) (iii) (d) What are the advantages of cloning? (Both traditional and modern)?: (e) Modern cloning includes tissue culture. Describe clearly, using words & diagrams, how tissue culture works: -7- Wellsway school science dept. Curriculum 2011 – AQA Science Biology workbook (f) Read the information on Embryo cloning. Explain the meaning of each these terms: (i) Artificial Insemination: (ii) In Vitro Fertilisation (IVF): (iii) Embryo: (iv) Surrogate (mother): (g) Draw a clearly labelled diagram summarising the main stages of embryo cloning. -8- Wellsway school science dept. Curriculum 2011 – AQA Science Biology workbook (h) Read the information about Adult Cell Cloning (Nuclear Transfer), & answer the questions which follow: Adult Cell Cloning (Nuclear transfer) is a two-part process: • • • firstly, scientists remove the nucleus from an unfertilised egg cell, secondly, they replace it with the nucleus of an older donor cell. A new clone—a genetically identical copy of the donor—forms when the egg starts to divide by mitosis. (i) Why is it necessary to remove the nucleus from the unfertilised egg cell? (ii) Which “parent” – the one which supplied the unfertilised egg, or the one which supplied the donor nucleus – will the new individual be identical to? Explain your answer: (iii) Suggest one advantage of producing animal clones by nuclear transfer. 7. Watch the video, MSS presentation or PowerPoint on Genetic Engineering (Artificial Gene Transfer). Read your textbook or support material on Genetic Engineering. Discuss with your teacher the processes involved in Genetic Engineering. (a) Read the sentences below on production of human insulin by Genetic Engineering. They are not in the correct order. Re-arrange them so that they are in the correct sequence. (rewrite them in the correct sequence in the space below if you wish): Genetic engineering means removing a gene from one living organism and putting it into another. This is how it has been used to help diabetics: 1. The bacterium makes insulin. 2. Special enzymes are used as chemical scissors. These cut out the insulinmaking gene from the rest of the DNA. 3. The bacteria multiply very rapidly. 4. The plasmid is put into a bacterium. 5. The human gene that codes for the production of insulin is identified. 6. All the bacteria produced will have the insulin gene. Lots of insulin will be made. 7. The human insulin-making gene is put into the plasmid. 8. A circular piece of DNA called a plasmid is removed from a bacterium. -9- Wellsway school science dept. Curriculum 2011 – AQA Science Biology workbook (b) Fill in the gaps in the following passage: Many inherited diseases are caused when the body cannot make a particular ____________. For instance, people with haemophilia cannot make the protein factor 8, which helps ___________ to clot. Diabetics cannot make the protein ____________. Genetic engineering makes it possible to make insulin quickly and cheaply on a _________ scale. The _________________ are grown inside huge industrial ____________________ called bioreactors. The microbes grow quickly under ideal conditions. Each bacterium is an identical ______________ ____________ with a copy of the insulin-making gene. The insulin is extracted and purified. Before genetic engineering, diabetics had to use insulin that had been extracted from __________ or pigs. This often produced reactions since it was different from ____________ insulin. Genetic engineering has also made it possible to produce large amounts of safer __________ much more quickly. WORD LIST: bacteria human blood insulin drugs large - 10 - fermenters protein genetic clone sheep Wellsway school science dept. 7. Curriculum 2011 – AQA Science Biology workbook Watch the video, MSS presentation or PowerPoint on Genetically Modified (GM) Crops. Read your textbook or support material on GM Crops. Discuss with your teacher the issues surrounding GM crop technology. Complete the table below to summarise the main advantages and drawbacks of GM crops: BENEFITS of GM crop technology 1. CONCERNS about GM crop technology 1. 2. 2. 3. 3. 4. 4. 5. 5. - 11 - Wellsway school science dept. Curriculum 2011 – AQA Science Biology workbook Why some species of plants and animals have died out, and how new species of plants and animals develop Changes in the environment of plants and animals may cause them to die out. Particular genes or accidental changes in the genes of plants or animals may give them characteristics which enable them to survive better. Over time this may result in entirely new species. There are different theories of evolution. Darwin’s theory is the most widely accepted. Candidates should use their skills, knowledge and understanding to: • interpret evidence relating to evolutionary theory • suggest reasons why Darwin’s theory of natural selection was only gradually accepted • identify the differences between Darwin’s theory of evolution and conflicting theories, such as that of Lamarck • suggest reasons for the different theories. Subject knowledge - Evolution a) The theory of evolution states that all species of living things have evolved from simple life-forms which first developed more than three billion years ago. b) Studying the similarities and differences between organisms allows us to classify living organisms into animals, plants and microorganisms, and helps us to understand evolutionary and ecological relationships. c) Evolution occurs via natural selection: • individual organisms within a particular species may show a wide range of variation because of differences in their genes • individuals with characteristics most suited to the environment are more likely to survive to breed successfully • the genes which have enabled these individuals to survive are then passed on to the next generation. d) Where new forms of a gene result from mutation there may be more rapid change in a species. 1. Watch the video on Evolution (B39), and whilst doing so answer the following questions. a. What does the theory of evolution state? b. What adaptations do the following animals have which improve their chances of survival in their environment? Snowshoe hare and Lynx: Tiger: Horses: Cheetah: c. What evidence exists to show us change in life over time? d. What evidence is there to suggest that all mammals have a common ancestor? e. What is natural selection? - 12 - Wellsway school science dept. Curriculum 2011 – AQA Science Biology workbook f. What do mutations introduce into a population? g. What do fossils / bones show us about life on Earth? 2. You will be given a piece of coloured card by your teacher to use as a background for this exercise. You will also be given a number of smaller different coloured pieces of card. Place these fairly evenly spread but in random order on the background card. Get a partner to as quickly as possible pick up 30 pieces of the smaller card one at a time. Record the number of each colour they picked up. Suggest a reason for the results. Do you think this is a good model for illustrating the effect of camouflage colouring in predator prey relationships? Try to think of positive and negative reasons! 3. Using the internet find out about Charles Darwin, and produce an A4 poster answering the following questions: What did he look like? When was he alive? Where did he live? What ideas did he have? Where did he travel? - 13 - Wellsway school science dept. 4. Curriculum 2011 – AQA Science Biology workbook During Darwin’s travels he made very important observations about populations of organisms. These are as follows: 1. Organisms produce more offspring than are needed to replace the parents. 2. Natural populations tend to remain stable over a long period of time. 3. There is variation amongst individuals of a given species. He used those observations to make some deductions that helped him come up with the theory of evolution. See how you do by answering the following! a) How many offspring need to survive per generation to maintain a population? b) For a population to stay stable what must happen to most of those organisms? Okay, so now you’ve realised that there is a struggle for survival. c) Why do some organisms survive and others die (try to give an example to help explain)? Most wild rabbits in the UK are of the agouti (brown) colour. However some will be born with white fur. d) What causes the rabbit’s fur colour? e) Why do the agouti coloured rabbits survive better? Let’s consider a scenario. Humans decide not to protect the environment. We decide to drive big cars, waste energy in the homes, don’t recycle paper, and keep replacing perfectly good mobiles, never re using plastic bags etc – all leading to emissions of green house gases. This causes melting of the polar caps, a cooling of the Gulf stream and a decline in temperature of the UK. f) Explain how the rabbit population might change over time. g) Why do you think that many people do not agree with Charles Darwin’s theory of evolution? 5. Natural Selection in Peppered moths. Read B4U, pg 301, then answer question 11 pg 326. a) i) - 14 - Wellsway school science dept. Curriculum 2011 – AQA Science Biology workbook a) ii) a) iii) b) c) 6. Is evolution still occurring? Warfarin is a poison used to kill rats. This chemical control method worked well until the 1960’s when some rats developed a resistance to the poison due to a mutation. a) What is a mutation? b) This has been called a ‘selective advantage’. What do you think this means? c) What do you think will happen to the rat population if Warfarin continues to be used? - 15 - Wellsway school science dept. 7. Curriculum 2011 – AQA Science Biology workbook Fill in the gaps to help test your understanding. Use the following words to help Change, Darwin, deeper, environment, , evolution, extinct, fossils, genes, natural selection, The theory of evolution tries to explain the ___________ in life that has ever existed on earth throughout time. Much of this evidence comes from ______________. Older fossils are found in the _______________ layers of rocks in places like the Grand Canyon. Those fossils found lower down are from organisms with less complex structures. Charles _____________was the scientist who proposed a mechanism for the process of ____________ in his book the Origin of species. Organisms that are best suited to their ______________________ will survive and breed. When they breed they pass on their useful ____________ to the next generation. Since it is ‘nature’ that determines the best characteristic this process is known as _____________ _______________. Therefore evolution happens via natural selection. If there is a change in the environment that a species does not adapt to deal with it may become ______________. This may occur due to the presence of disease, new predators, or climate change. Well done! You have now completed the Variation, Genetics & Evolution topic. Useful web links. http://www.bbc.co.uk/schools/gcsebitesize/biology/variationandinheritance/4cloningandgenengrev5.shtml http://www.s-cool.co.uk/topic_quicklearn.asp?subject_id=17&Topic_ID=13&Quicklearn_ID=4&loc=ql www.defra.gov.uk/environment/gm1fse; www.nature.com www.gmsciencedebate.org.uk www.gmnation.org.uk www.wellcome.ac.uk/labnotes (number 2) http://www.pnas.org/misc/classics4.shtml GM Animals www.royalsoc.ac.uk/scienceinsociety www.royalsoc.ac.uk/policy/index.html www.hse.gov.uk/foi/openacgm.htm www.bbc.co.uk/genes http://www.bbc.co.uk/schools/gcsebitesize/biology/variationandinheritance/ http://www.biotopics.co.uk/genes/varn.html http://www.s-cool.co.uk/topic_principles.asp?loc=pr&topic_id=10&subject_id=17&ebt=70&ebn=&ebs=&ebl=&elc=4 http://octopus.gma.org/surfing/antarctica/penguin.html http://users.rcn.com/jkimball.ma.ultranet/Biologv Pages/E/Evolution .html www.naturedetectives.org.uk - 16 - Wellsway school science dept. Curriculum 2011 – AQA Science Biology workbook 8. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Glossary - Variation. (Muddled – sort them out!) Asexual reproduction Genetically identical offspring, produced by mitosis Characteristic Variation with only a few discrete categories e.g. eye colour Clone Reproduction involving only 1 parent, producing clones Continuous variation Variation with many different categories e.g. human height Discontinuous variation An observable feature, caused by genes, environment or both Embryo Joining together of male and female sex cells (gametes) Fertilisation Variation caused by changes in DNA in genes Gamete Individuals with exactly the same genes i.e. clones Genetically identical Early stage in development of an animal or plant Genetic variation Sex cell, male or female, e.g. egg, sperm, pollen Ionising radiation Change in DNA in genes, causing changed characteristics Meiosis Radiation which causes mutations by damaging DNA e.g. X rays Mitosis Reproduction involving fusing of male & female gametes Mutagenic Differences in characteristics between individuals Mutation Cell division which produces genetically identical daughter cells Sexual reproduction Something which causes mutations e.g. radiation, cigarette tar Variation Cell division which produces genetically different gametes 9. Glossary – Cloning/Genetic Engineering. (Muddled – sort them out!) Artificial Insemination Separating embryos which then grow into genetically identical offspring Asexual reproduction Injecting sperm into a female animal to fertilise her egg(s) e.g. impregnating cows with bull sperm Clone 1st animal ever cloned by nuclear transfer Dolly the sheep One parent produces genetically identical offspring Embryo cloning Any organism which is genetically identical to another Fermenter An organism with 1 or more genes added to change its characteristics e.g. GM soya bean plants Genetic engineering Hormone which controls blood sugar levels, now made from genetically modified bacteria to treat diabetes Gene Large container for growing bacteria on a large scale Genetically modified Artificial transfer of genes e.g. from human cells to bacteria Insulin Length of DNA which controls the production of a particular protein. Genes produce all inherited characteristics In Vitro fertilisation Mother implanted with a fertilised egg/embryo which can then develop inside her Mitosis Growing one or a few cells into a tissue, organ or organism Nuclear transfer Short loop of bacterial DNA used to transfer genes from other organisms into bacteria, e.g. human insulin gene Plasmid Cell division in asexual reproduction/cloning – produces genetically identical cells/offspring Surrogate IVF - removing eggs from a female & fertilising them with sperm in a test tube Tissue culture Removing the nucleus from an egg cell & replacing it with a nucleus from a donor cell 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 - 17 - Wellsway school science dept. 10. 1 2 3 4 5 6 7 8 9 10 11 Curriculum 2011 – AQA Science Biology workbook Glossary - Evolution. (Muddled – sort them out!) Evolution The remains of a living thing that have been preserved over time Charles Darwin A change in a gene Organism A poison that interferes with blood clotting. Used to Kill rats. Adaptation The concept developed by Charles Darwin that genes which produce characteristics that are more favourable in a particular environment will be more abundant in the next generation Methicillin Resistant Staphylococcus aureus – a bacterium Peppered moth mutation The man who proposed a mechanism for evolution Natural selection A characteristic that suits an organism to its environment Fossils A type of antibiotic Warfarin Anything living MRSA Used as classic example of how change in the environment can cause a change in a population Methicillin Change in life over time 11. Additional Notes. - 18 - Wellsway school science dept. Curriculum 2011 – AQA Science 12. Questions – Variation. - 19 - Biology workbook Wellsway school science dept. Curriculum 2011 – AQA Science 13. Questions – Cloning & Genetic Engineering. - 20 - Biology workbook Wellsway school science dept. Curriculum 2011 – AQA Science - 21 - Biology workbook Wellsway school science dept. Curriculum 2011 – AQA Science - 22 - Biology workbook Wellsway school science dept. Curriculum 2011 – AQA Science 14. Questions - Evolution. - 23 - Biology workbook Wellsway school science dept. Curriculum 2011 – AQA Science 6 5 - 24 - Biology workbook Wellsway school science dept. Curriculum 2011 – AQA Science 7. - 25 - Biology workbook