最新选修八第二单元课件 Cloning

Para 1
A.The problems of Dolly
Para 2
B.The two major uses and procedures
of cloning
Para 3
源自文库
C.The impact of cloning Dolly
Para 4
D.The definition of cloning
Para 5
Careful-reading Task1: （para1-2)
3. Why is it easier to make commercial plant clones than animal clones?
Because cloning plants is straightforward while cloning animals is very complicated.
E. People’s reaction to cloning
Fast-reading 2. The main idea of the text is ______.
A. Animal cloning is very valuable and can benefit the world. B. Animal cloning could be misused by bad people so it must be forbidden. C. Animal cloning is well developed because Dolly the sheep was born. D. Animal cloning raised arguments and scientists are not sure about its future.
A. Cloning can be used for medical purposes.
B. Large quantities of food can be produced by cloning.
C. Cloning can help keep animals from becoming extinct.
3.What benefits can human gain from cloning?
4.What problems may arise when humans are cloned?
Reading:
Fast-reading (5 minutes)
1. Scan the following passage and match the paragraph with the correct sentence.
B.B. usually lives longer than the original one
C.C. usually lives shorter than the original one
D.D. is usually as healthy as the original one
2. Which of the following is not an advantage of cloning?
Careful-reading Task1: （para1-2)
1.What is cloning?
2. Cloning is a way of making an exact copy of another animal or plant.
Careful-reading Task1: （para1-2)
Man-made clone is one that is produced through human
intervention(介入) .
Discussion
Look at the following pictures and discuss which ones are natural clones and which ones are man-made clones.
选修八第二单元课件 Cloning
Dolly the sheep
How does Dolly differ from other sheep? Dolly was cloned while the others were born naturally.
Natural clone is one that occurs in a natural form of cloning without human help.
Natural or man-made clones?
A strawberry plant
一株草莓依靠它沿地“爬走”的匍匐茎,一年 内就能长出数百株草莓苗。
Growing new plants
Twins
Do you want to know:
1.What is a clone?
2.How is a clone is produced?
Careful-reading
推理判断题
Task2: （para3-5) (4minutes)
1. It can be inferred from the passage that a cloned animal_____.
A. usually lives as long as the original one
Careful-reading
Task1: （para1-2) (3 minutes)
1. What is cloning?
2.What are the two major uses of cloning?
3. Why is it easier to make commercial plant clones than animal clones?
2. What are the two major uses of cloning? The first use is to produce commercial
quantities of plants. The second is to research on new plants
species and do medical research on animals.