What is cloning?
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Cloning occurs naturally in some plants and in human identical twins, and it
is now possible to clone animals artificially. Clones are genetically identical
individuals. Bacteria, plants, and some animals, can reproduce asexually to
form clones that are genetically identical to their parent. Identical human
twins are also clones. Any differences between them are due to
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In nature, some plants and single-celled organisms, such as bacteria, produce
genetically identical offspring through a process called asexual reproduction. In
asexual reproduction, a new individual is made.
Natural clones, also known as identical twins, occur in humans and other
mammals. These twins are produced when a fertilized egg splits, creating two
or more embryos that carry almost identical DNA. Identical twins have nearly
the same genetic makeup as each other, but they are genetically different from
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People may want to clone an animal deliberately.
Just like the cloning of plants, the cloning of animals has many important
It allows an individual animal with desirable features, such as a cow that
produces a lot of milk, to be duplicated several times.
But the process is more complex than it is with plants.
People may want to clone a plant deliberately, that is produce lots of
identical new plants. Cloning of plants has many important commercial
implications: it allows a successful variety of a plant to be produced
commercially and cheaply in a short space of time and on a massive scale.
Ways of cloning
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Asexual reproduction needs only one parent, unlike sexual reproduction, which needs
two parents. Since there is only one parent, there is no fusion of gametes and no
mixing of genetic information. As a result, the offspring are genetically identical to the
parent and to each other.They are clones.
A developing embryo is removed from a pregnant animal at an early stage, before the
embryo's cells have had time to become specialised. The cells are separated, grown for
a while in a laboratory, and then transplanted into host mothers.
When the offspring are born, they are identical to each other. They are not identical to
their host mothers, because they contain different genetic information (the offsprings'
DNA comes from the original pregnant animal and the father).
Advantages of cloning
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Human cloning technology could be used to reverse heart attacks.
Scientists believe that they may be able to treat heart attack victims by cloning their
healthy heart cells and injecting them into the areas of the heart that have been
Infertility. With cloning, infertile couples could have children. Despite getting a fair
amount of publicity in the news current treatments for infertility, in terms of
percentages, are not very successful.
Down's syndrome. Those women at high risk for Down's syndrome can avoid that risk
Disadvantages of Cloning
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If a clone is susceptible to disease or changes in environment, then all the clones will
It will lead to less variation, and less opportunity to create new varieties in the
Cloning children could foster an understanding that children can be designed and
replicated to the parents’ wishes.
There would be a lack of uniqueness and violate convictions regarding human
individuality and freedom. Clones could be seen as less than human compared with
Advantages and Disadvantages table
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Helps with organ donations Causes less varation in species
Can help with less extinction Cannot fight diseases easily
Can reverse heart attacks Violates human law
Can stop infertility Every one would be the same
Can avoid down syndrome No evolution would occur
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