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THE CLONE FACTORY. Animal Cloning : Is It a S cientific Miracle ?. What is Animal Cloning?. Animal Cloning is the process by which an entire organism is reproduced from a single cell taken from the parent organism and in a genetically identical manner.
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What is Animal Cloning? Animal Cloning is the process by which an entire organism is reproduced from a single cell taken from the parent organism and in a genetically identical manner. This means the cloned animal is an exact duplicate in every way of its parent; it has the same exact DNA.
Development of Animal Cloning in the Lab Scientists have been attempting to clone animals for a very long time. Many of the early attempts came to nothing. The first fairly successful results in animal cloning were seen when tadpoles were cloned from frog embryonic cells. This was done by the process of nuclear transfer. The tadpoles so created did not survive to grow into mature frogs, but it was a major breakthrough nevertheless.
After this, using the process of nuclear transfer on embryonic cells, scientists managed to produce clones of mammals. • The first successful instance of animal cloning was that of Dolly the Sheep, who not only lived but went on to reproduce herself and naturally. Dolly was created by Ian Wilmut and his team at the Roslyn Institute in Edinburgh, Scotland, in 1997.
Dollythesheep…. After hundreds of tries, Scottishscientists successfully took a cell from an adult sheep, fused it to another sheep’s unfertilized egg and implanted the resulting embryo in a surrogate mother. But Dolly’s birth gave way to fears and speculation about what this discovery meant for humanity’s ability to manipulate biology.
Since then Scientists have been successful in producing a variety of other animals like rats, cats, horses, bullocks, pigs, deer, etc. You can even clone human beings now and that has given rise to a whole new ethical debate. Is it okay to duplicate nature to this extent? Is it okay to produce human clones? What would that do to the fabric of our society?
Now animal cloning can be done both for reproductive and non-reproductive or therapeutic purposes. In the second case, cloning is done to produce stem cells or other such cells that can be used for therapeutic purposes, for example, for healing or recreating damaged organs; the intention is not to duplicate the whole organism.
Points against Animal Cloning In a large percentage of cases, the cloning process fails in the course of pregnancy or some sort of birth defects occur, for example, as in a recent case, a calf born with two faces. Sometimes the defects manifest themselves later and kill the clone.
Points for Animal Cloning On the favorable side with successful animal cloning you know exactly how your clone is going to turn out. This becomes especially useful when the whole intention behind cloning is to save a certain endangered species from becoming totally extinct.
Do youknowabout… • massproduction of chickens? • batteryfarms (animalsareheld in smallsheds) ? • free-rangechickens ( animalsthatroamfreelyforfoodratherthanbeingconfinedindoors) ? • freerangeeggs?
vocabulary era (n) : time period The discovery of antibiotics marked an era in modern medicine.
massive (adj) : large, bulky PeoplebelievedthatthreemassivestoneblocksbeneaththeTemple of JupiterBaalwereplacedbygiants.
rate (n) : ratio, proportion Itmightsurpriseyoutohearthatlawyersaresuiciding at an alarmingrateacrossthe United States.
prospect (n) : outlookforfuture Thetraining he gotlastsummeroffered a prospect of continuousemployment.
scaleup (v) : toincreasethe size, amountorimportance of something Thankstonewinvestments, manufacturingcapacity has beenscaledup.
teamup (v) : to form a groupwithotherpeople in ordertodo somethingtogether He teamedupwiththebandtoproducethealbum.
modify (v) : alter, change Shemay be preparedtomodifyher views.
envisage (v) : consider, imagine, visualize He envisagesthepossibility of establishingdirectdiplomaticrelations in thefuture.
vulnerable (adj) : opentoattact • Smallfisharevulnerabletopredators. • The scheme will help charities working with vulnerable adults and young people
adopt (v) : chooseortakesometing as one’sown Thisapproach has beenadoptedbythemajority of banks.
UsefulExpressions Rolloff (theproductionline) Massproduction Keeppacewithsomething Fallvictimtodisease Be fit forsomebody
FOCUS QUESTIONS • 1. How do thegoals of researchersandfarmersdiffer? • 2. What is thedifferencebetween a cloneand a chimera? • 3. WhatareOrigen’stwomajorchallenges?
READING COMPREHENSION Lookingforthemainideas: 2. Becausetheygrow at thesame rate, havethesameamount of meat, andtastethesame.
4. Theadvantages of mass-producingidenticalchickensarethatthebirds can be madeto be disease-resistant, they can growquicklyandwithlessfood, andfarmers can adoptstrainsthatdon’tcarryfood-poisoningbacteria.
Thedisadvantagesarethatmanyembryosdie, morebirdsgo lame becausetheir bone growthcannotkeeppacewiththeirmusclegrowth, andwhenonebird is vulnerableto a disease it affectsalltheclones.
Skimmingandscanningfordetails 1. Itmeanstheprospect of cloningchickens. 2. A chimera is created in a two-step process. First, embryonicstemcellsareremovedfrom a freshlylaid, fertilizedegg. Thenthesedonorcellsareinjectedintotheembryo of anotherfreshlylaid, fertilizedrecipientegg.
3. A chimeracontainscellsfrombothdonorandrecipient. A clonecontainsonlydonorcells.
4. Origenplanstoscaleupproduction of geneticallyengineeredchickensbyusingmachinesthat can inject 50,000 eggseachhour. 5. Origen’sfirstchallenge is tocreate a chimera.
6. Thediscrepancy is thatOrigen’s Web site discussestheprocess of engineeringbirdsthatlayeggscontainingmedicaldrugs, yet Origen’sspokespersonsaysthatthecompany is not consideringgeneticmodification.
