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24 Sheets 24 Questions 24 Answers You have 5 minutes to learn them all B1: You and your Genes: Revision
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B1: You and your genes What makes every person in the world unique?
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B1: You and your genes What effect does the environment have on your features ?
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B1: You and your genes What are stem cells and what is stem cell research?
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B1: You and your genes Which animals use asexual reproduction?
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B1: You and your genes What factors separate genetically identical twins?
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B1: You and your genes What ‘s the chance of being male or female?
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B1: You and your genes What is gene therapy?
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Twenty Four Questions Short or one word answers on paper. 30 seconds for short answers / 60 seconds for longer ones. How will you score? 22 / 24 = A* 20/24 = A 16/24 = B 12/24 = C 8/ 24 = D
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Predict Your Score Now! What mark & grade do you think you will get? 22 / 24 = A* 20/24 = A 16/24 = B 12/24 = C 8/ 24 = D
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1. What is environmental variation? 2. Name two types of sex cell. 3. What are genetically identical organisms called?
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4. Write these cell parts in order starting with the smallest: chromosome, gene, cell, nucleus 5. What can an embryonic stem cell become? 6. How many chromosomes are there in: a) an ‘ordinary’ human cell b) a human sex cell (gamete)?
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7. 7. Where do you find a human embryo ? 8. 8. What scientific ‘f’ word immediately precedes the formation of a zygote ? 9. 9. Name one life-threatening illness which is inherited.
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10. 10. What is variation? 11. 11. Males have two XX chromosomes. True or False? 12. 12. What is an allele?
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13. Explain briefly what is meant by ‘an ethical question.’ 14. A genetic test for cystic fibrosis turns out to be a ‘false negative.’ What does this mean ? 15. What is the method for choosing a healthy embryo called?
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16. 16. Is the allele for cystic fibrosis dominant or recessive? 17.Define asexual reproduction. 18. Write down one viewpoint in support of embryo selection.
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19. Write down one viewpoint that does not support embryo selection. 20. How does gene therapy work? 21. 21. What is genetic modification?
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21.What is Huntingdon’s Disorder? 23. What are chromosomes? 24. What is cystic fibrosis?
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1. What is environmental variation? 2. Name two types of sex cell. 3. What are genetically identical organisms called? Variation that occurs in the features of a living organism as a result of factors in the environment. Darker skin from more sun; a scar from an injury, hair style, tattoos…… sperm cell and egg cell clones
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4. Write these cell parts in order starting with the smallest: chromosome, gene, cell, nucleus 5. What can an embryonic stem cell become? 6. How many chromosomes are there? a) ‘ordinary’ human cell b) a human sex cell Gene is found on the chromosome which is found in the nucleus of the Cell. Any type of cell. It’s unspecialised ‘ordinary’ - 46 / sex cell 23
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1. What is environmental variation? Environmental variation in skin. Discuss. Maori face tattoo ‘embedded’ tattoos Mouth tattoo
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1. What is environmental variation? Environmental variation in legs. Discuss. model cross- country runner bodybuilder sprinter
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3. Clones are genetically identical organisms Plants: natural cloning by asexual reproduction Advantages of asexual reproduction to the plant: - many new plants very quickly. - no need to produce flowers or gametes saving energy. - no risk of failure to pollinate or fertilise.
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3. Clones are genetically identical organisms Animals: natural cloning by asexual reproduction Simple animals like hydra have unspecialised cells - These cells can become any type of cell. - These cells can also grow a whole new hydra - Like plants; hydra keep these unspecialised cells for life
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3. Clones are genetically identical organisms Identical twins: have the same genes but… …they come from both parents. - They are clones of each other but… - …not of either parent - These are clones from sexual reproduction
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A ___________ egg cell divides many times to produce an _________. Sometimes the early ball of cells can split into two separate groups. Both of these groups of cells develop into a new person. They are ___________ twins because they both come from the same fertilised egg cell, so they have exactly the same ________. The fertilized egg cell had a __________ of their parents’ genes, so the twins are not genetically identical to either parent. embryo identical genes fertilised mixture Identical Twins fertilised embryo identical genes mixture
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7. 7. Where do you find a human embryo ? 8. 8. What scientific ‘f’ word immediately precedes the formation of an embryo ? 9. 9. Name one life-threatening illness which is inherited. In the uterus fertilisation Huntingdon’s disorder, cystic fibrosis
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10. 10. What is variation? 11. 11. Males have two XX chromosomes. True or False? 12. 12. What is an allele? False. Male sex chromosomes are X and Y. They are different versions of the same gene. They are the code for inherited features. There could be two dominant, two recessive or one of each. Differences between living organisms. This could be differences between species but there are also differences between members of a population from the same species (as in humans)
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B1: Variation Human beings are all very __________. We share many of the same __________. But each person is ___________. There are differences in our features. We call these differences __________. Differences between us are caused by ________ and the ___________ or a mixture of both. Genes are found in the __________ of cells and are instructions for making __________. genes proteins alike variation nuclei environment unique features alike featuresunique variation genes environment nuclei proteins
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Men wear Y-fronts. & There’s a ‘Y’ in boY. Males are XY Learn the XX / XY fact any way you like and then remember it because it’s easy marks! Females are XX
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Girls are useless Boys know why, Girls aren’t the bosses. Boys X and Y Girls krissy-krosses. XX Yes the poems are rubbish, so find your own way to remember XX / XY because it’s easy marks Males are XY Females are XX Boys are useless Boys must cry, Girls are the bosses. Boys X and Y Girls two big crosses. XX
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During fertilisation the ______ chromosomes in the sperm combine with the ______ chromosomes in the egg to form 23 ________ of chromosomes. Each chromosome in a pair has come from a __________ parent. This means there may be different versions of the genes – called __________. Because children get their alleles from both parents they tend to ________ both parents but never look ___________ the same as either one. different pairs resemble alleles exactly 23 12. What is an allele? 23 pairs different alleles resemble exactly
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Genetic Cross Diagram >>>>>>>> A capital letter codes for the dominant allele (B) A small case letter codes for the recessive allele (b) In this example both the mother and the father are Bb They both have brown eyes The allele for blue eyes is b and is recessive What’s the possibility of them having a blue-eyed child? BbBb B bbbBb BbBB 12. What is an allele?
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B is the gene for brown eyes b is the gene for blue eyes Parents BBbb Body cell in father with a pair of genes for brown eyes Body cell in mother with a pair of genes for blue eyes Gametes B each sperm has a gene for brown eyes bbeach ovum has a gene for blue eyes B At fertilization There are 4 possible ways of joining a sperm to an ovum BBBB b BbBb BbBb What’s the possibility of them having a blue-eyed child?
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Parents father with brown eyes mother with brown eyes Gametes At fertilization B is the gene for brown eyes b is the gene for blue eyes Bb Bb Bb BbBb bbBb BbBB A child who inherits the genes BB will have brown eyes A child who inherits the genes Bb will have brown eyes A child who inherits the genes bb will have blue eyes
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13. Explain briefly what is meant by ‘an ethical question.’ 14. A genetic test for cystic fibrosis turns out to be a ‘false negative.’ What does this mean ? 15. What is the method for choosing a healthy embryo called? One for which there is no definitive right or wrong. A difficult choice. The test result said the embryo was clear of cystic fibrosis and therefore ‘negative.’ But the result was wrong and the child was born with cystic fibrosis. Genetic tests are not completely reliable. embryo selection (pre-implantation genetic diagnosis)
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16. 16. Is the allele for cystic fibrosis dominant or recessive? 17.Define asexual reproduction. 18. Write down one viewpoint in support of embryo selection. Recessive. Cystic fibrosis can only be passed on when two recessive alleles are present. When an organism has offspring without a mate. The offspring have just one parent. Parents can choose between embryo’s. (If an embryo is identified as having Huntingdon’s or cystic fibrosis they can choose a different one).
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14. A genetic test for cystic fibrosis turns out to be a ‘false negative.’ What does this mean ? This question is a genetic testing one: Fetus has the disorder Fetus does not have the disorder Fetus has the disorder Fetus does not have the disorder Fetus has the disorder Reality Test result False negative False positive True negative True positive Outcome Genetic testing is approximately 90% accurate
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19.Write down one viewpoint that does not support embryo selection. 20.How does gene therapy work? 21.What is genetic modification? It is the process of replacing faulty alleles with healthy ones. Altering the characteristics of an organism by introducing the genes of another organism into it’s DNA. a.It’s wrong to create one person to help another or b.It’s a step towards ‘designer babies.’ Nature should be allowed to take it’s natural course or c.They could might think about producing babies as organ donors.
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20. How does gene therapy work?
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22.What is Huntingdon’s Disorder? 23.What are chromosomes? 24.What is cystic fibrosis? An inherited disease of the nervous system. Threads of genes found in the nucleus of a cell. A genetic inherited disease caused by recessive alleles that affects many organs particularly the lungs and digestive system.
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What did you score? Task: You have 2 minutes to identify and list your 3 weakest areas from the next page in your planner. 22 / 24 = A* 20/24 = A 16/24 = B 12/24 = C 8/ 24 = D
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Inheritance / Variation GenesChromosomes Huntingdon’s disorder Cystic fibrosis Male or female? Dominant alleles Recessive alleles Ethics – making decisions Genetic testing Embryo selection Gene Therapy Cloning Asexual reproduction Sexual reproduction Therapeutic cloning What makes us all different?..and chromosomes Numbers in ‘normal’ cells and sex cells Inherited condition / symptoms Inherited condition / carriers XY / XX - sperm and egg cells Alleles that create your features Alleles you carry – not as features …about what’s ‘right’ and what’s ‘wrong’ Used to look for faulty alleles H: Pre-implantation genetic diagnosis Replacing faulty alleles with healthy ones Ethics of laboratory cloning. Dolly. Natural cloning Creating offspring from two adults Use of stem cells to create new cells
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Lesson: Your B1 Revision: 3 Choices Pair up with another student. Work as a team. Support each other. Help each other out. Choice 1: Make up 5 questions (with answers) for each weak area. 15 questions in all. Test each other. Choice 2: Draw a memory diagram of your weakest area. (I’ll show you an example of how to do this). Choice 3: Plan a B1 revision lesson to teach your partner (and yourself) about one of your weak areas. It must include an introduction, some annotated diagrams and some questions to ask the ‘class.’
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Higher Students – Your A* awaits – Part 1 Understand: genes are instructions for a cell that describe how to make proteins, which may be structural or enzymes; genes are instructions for a cell that describe how to make proteins, which may be structural or enzymes; that sex of a human embryo is determined by a gene on the Y chromosome; that sex of a human embryo is determined by a gene on the Y chromosome; link between this gene and the development of sex organs into either ovaries or testes. link between this gene and the development of sex organs into either ovaries or testes. implications of testing embryos for embryo selection; pre- implantation genetic diagnosis (PGD); implications of testing embryos for embryo selection; pre- implantation genetic diagnosis (PGD); the implications of the use of genetic testing by others, (eg. for genetic screening programmes, by employers / insurance companies). the implications of the use of genetic testing by others, (eg. for genetic screening programmes, by employers / insurance companies). Abbreviate these to your planner
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Higher Students – Your A* awaits – Part 2 ---in the context of use of genetic testing by others you can: distinguish what can be done (technical feasibility), from what should be done (values); distinguish what can be done (technical feasibility), from what should be done (values); explain why different courses of action may be taken in different social and environmental contexts. explain why different courses of action may be taken in different social and environmental contexts. ---understand how clones of animals occur: naturally, when cells of an embryo separate (identical twins); naturally, when cells of an embryo separate (identical twins); artificially, when the nucleus from an adult body cell is transferred to an empty unfertilised egg cell. artificially, when the nucleus from an adult body cell is transferred to an empty unfertilised egg cell. Abbrevaite these to your planner
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Revision Homework Create a Powerpoint presentation on your weakest areas Use the 15 questions you worked out as your starting point. Explain ‘difficult’ science parts as simply as you can. Use relevant diagrams & photographs from the internet. Next week : ‘trade’ your Powerpoint with other students.
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Some Extra B1 Stuff
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Inheritance Children inherit their __________ from their mother and their __________. So children may look a bit like their parents. Each child gets a mix of their parents genes so brothers and sisters may look ___________ but they will all be __________ because they get a different ___________ of their parents genes. Your ____________ containing your genes are in pairs. alike genes chromosomes father unique mixture genes father alike uniquemixture chromosomes
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The 23 rd pair of chromosomes in humans decides if you are male or female. They are called the ______ chromosomes. There are two types, the ____ chromosome which can be found in eggs or sperm, and the _____ chromosome, which is found in _____ cells but never in _____ cells. Somebody with the chromosomes _____ would be male, whereas someone with the chromosomes _____ would be female. XX sex XY sperm Y egg X Male or female? sex X Y sperm egg XY XX
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Male or female? Human beings have _____ pairs of chromosomes in a normal body cell. One pair is called the _____ chromosomes. This pair controls whether the person is male or female. In a man the chromosomes in this pair are different sizes. There is one _____ and one _____ chromosome. In a woman the chromosomes in this pair are the same size. There are two _____ chromosomes. The pair is called _____. XX X 23 X sex XY Y 23 sex XY X XX
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