新人教版英语选修八第二单元新授课课件

2001 cloning cattle
我国成功繁殖克隆兔 体形要比普通兔大许多
2002年5月 中旬成功地 繁殖了一只 胚胎细胞克 隆兔。
2002 cloning cats
第一只克隆宠物猫
克隆马及其“母 亲兼姐姐”
2002年4月十六 日美国第一头 克隆牛“艾米” 产下牛犊喜作 妈咪
2005 cloning dogs
2. How is clone produced?
This happens in plants when gardeners take cuttings from growing plants to make new ones, and when small parts of a plant are taken and grown in a laboratory. It also happens in animals when twins identical in sex and appearance are produced from the same original egg.
3. What benefits can human gain from cloning?
1)It can help cure serious diseases 2) It can help couples who have no baby to bear a new baby.
4. What problems may arise when human beings
A strawberry plant
The new plants that grow from the runners are exact copies of the original 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
仙人掌每块落地就生根 富贵竹插枝即活
基因就会发生相同的变化。
Natural clone is one that occurs in a natural form of cloning without human help.
Man-made clone is one that produced through human intervention(介入) .
are cloned?
1)People may want to clone themselves so that they can live for ever. 2)People want to clone dead children 3).People may want to clone their favorite pets
Discussion
In pairs, look at these pictures and discuss which ones are natural clones and which ones are manmade. Explain how they differ.
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
Pre-reading
List the questions you want to find out
1. What is clone?
2. How is clone produced?
3. What benefits can human gain from cloning?
4. What problems may arise when human beings are cloned?
克隆的基本过程是先将含有遗传物质的供 体细胞的核移植到去除了细胞核的卵细胞 中,利用微电流刺激等使两者融合为一体, 然后促使这一新细胞分裂繁殖发育成胚胎, 当胚胎发育到一定程度后,再被植入动物子 宫中使动物怀孕,便可产下与提供细胞者基 因相同的动物。这一过程中如果对供体细 胞进行基因改造,那么无性繁殖的动物后代
Watch the video : The Cloning Technology of China
http://v.youku.com/v_playlist/f4121865o1p4.html
克隆,是Clone的译音,意为生物体通过细胞进行 的无性繁殖形成的基因型完全相同的后代个体组 成的种群,简称为“无性繁殖”。 “克隆”一词 于1903年被引入园艺学,以后逐渐应用于植物学 、动物学和医学等方面。克隆与无性繁殖是不同
克隆的荧光小猪(左)和正常小猪(右)
富贵竹插枝即活
The gardener should cut the plant ,then the cutting produce another new plant.
Twins
They are born naturally and identical in sex and appearance.
1. What is clone?
Clone is a way of making an exact copy of another animal and plant; A clone is group of cells or organisms that are genetically identical and have been produced asexually from the same original cell. They include natural and man-made clones.
的。
无性繁殖是指不经过雌雄两性生殖细胞的结合、 只由一个生物体产生后代的生殖方式,常见的有 孢子生殖、出芽生殖和分裂生殖。由植物的根、 茎、叶等经过压条或嫁接等方式产生新个体也叫 无性繁殖。绵羊、猴子和牛等动物没有人工操作 是不能进行无性繁殖的。科学家把人工遗传操作 动物繁殖的过程叫克隆,这生物技术叫克隆技术
Βιβλιοθήκη Baidu
Twins
Dolly the sheep
How does Dolly differ from other sheep? She was cloned while the others were born naturally. Dolly was a _c_l_o_n_e_dsheep.
1996 cloning sheeps