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Unit 2
Cloning
the important events in
cloning history
In 5000B.C. ( 谷物选种)
Human Beings began to choose the
best seeds from some kinds of crops. That
was the beginning of controlling life
according to human’s will.
In 1952: Cloning tadpole ( 克隆蝌蚪)
The American scientists
created a copy of tadpole by means of
using a tadpole cell. This tiny tadpole has
become the first kind of cloning animal.
• In 1978: The first case of
tube infant (试管婴儿 )
appeared.
☆A British doctor used the
sperm（精液）of a man
and fertilized(受精 ) it in a
test tube(试管).
☆Then transplanted(移植)
the embryo(胚胎) into the
womb(子宫 ) of a healthy
mother.
☆The first tube infant called
Louis appeared.
In 1996, the famous sheep “Dolley”
was cloned successfully
Dolley and
the Father
of Dolley –
Ianwilmut
( 伊恩.威尔
姆)
• In 1998 A series of
things were cloned.
• The scientists in
Hawaii University
cloned over 50 mice.
• Some private
institutions
( 协会 ) successfully
cloned little oxen.
In 2002, the
scientists of A&M
University in USA
has bred the first
cloned cat in the
world.
Nowadays :
☆ Cloned dog, mouse,
rabbit, goat, ox, pig
appeared .
☆ China become the
seventh country that has
the ability to clone pigs.
☆ China has succeeded in
using embryonic（胚胎的）
cell to clone many animals.
the important events in
cloning history
Warming up
( 4ms )
Answer the following questions:
1. Do you like dinosaurs? Where have you
seen them? Can you see them in our
real life? Why?
2. Do you think it is possible to clone
dinosaurs? If yes, do you think that’s
good for human beings? Why?
( Students give their own answers.)
Reading -- I scanning ( 5ms )
Read the text, then tell the following sentences are true
or false. ( Students can discuss in pairs. )
1. Scientists are still experimenting with cloning
mammals because they think it can make
money. F
2. The animals that have disappeared from the
earth, like dinosaurs, can be brought back to
life through cloning. F
3. If we can clone any extinct animals, we should
let them live in a zoo. F
Reading -- II Detail reading ( 6ms )
Read the text, then answer the following
questions. ( Students can discuss in pairs. )
1. Why should’t you clone an extinct animal
unless there is enough diversity in the
group?
2. Why is it wrong to clone an extinct animal
if it would have to live in a zoo?
3. Why can’t you clone the DNA of animals
that have been extinct longer than 10,000
years?
1. Why should’t you clone an extinct animal
unless there is enough diversity in the group?
There will not be enough genetic variation in the
group to be able to resist new illnesses.
2. Why is it wrong to clone an extinct animal
if it would have to live in a zoo?
It is not a good idea to clone an animal
that would have to live in a zoo because it
is not a suitable habitat to develop and
increase its numbers.The zoo is not a
natural environment for a wild animal.
3. Why can’t you clone the DNA of animals that
have been extinct longer than 10,000 years?
The DNA of animals more than 10,000 years old
is not suitable for cloning ,for it can’t survive so
long.
Reading -- III Argument ( 10ms )
1. Read the passage again and have a
argument according to the requirement of
Ex.2 on Page 16.
2. Students work in groups, when discussing,
the head of each group should write down the
opinions of all the members.
3. Ask some volunteers to show their opinions.