Unit 5 Lesson 29 DNA—The Story of You课件＋音频(共25张PPT) 冀教版九年级全一册

(共25张PPT)
Unit 5
Look into Science
Lesson 29
1. Do you look the same with your sister or brother
Your DNA comes from your parents.
3. Why
2. Do you look like your mother
Free Talk
What's DNA
DNA is the blueprint of life.
How tall are you What colour are your eyes What size are your feet All these things are strongly influenced by your DNA before you are born!
This is the shape of DNA.
Do you think it’s magic Let's learn a new lesson and find out how fantastic DNA is!
1. To understand the meaning and usage of the new words and expressions.
2. To know more about DNA.
3. To learn more about human beings and enjoy science.
学习目标
DNA [ di en e ] blueprint [ blu pr nt]
general [ d enr l] complex [ k mpleks]
twin [tw n]
repeat [r pi t]
脱氧核糖核酸
n. 蓝图
adj. 一般的;普遍的
adj. 复杂的
n. 双胞胎之一
v. 重复;复述;背诵
New words and expressions.
新课讲授
pattern [ p tn]
identify [a dent fa ]
related [r le t d]
grandson [ ɡr ns n]
granddaughter [ ɡr nd t (r)] instruction [ n str k n]
n. 模式;形式
v. 确认;鉴别
adj. 有关的;相关的
n. 孙子;外孙
n. 孙女;外孙女
n. 指示;说明
1. for some twins, every living thing has its own unique DNA.
2.Some problems can be caused by problems in your DNA.
3.Your finger has the DNA as your hair.
4.From your DNA, can identify not only you, but also people who are related to you.
5. DNA is one of the amazing things on the earth!
health
scientists
most
same
Listen to the text and fill in the blanks.
Except
Listening
① Read the lesson and answer the questions.
1. What is a blueprint
2. Which is more complex, building a living thing or building a house
3. Do some twins have the same DNA
4. Is it possible to change your DNA
5. Whose DNA is related to yours
A blueprint is a drawing that shows how to put a house together with many different parts.
Building a living thing.
Yes, they do.
Yes. In the future, scientists might be able to change our DNA.
People who are related to me. For example, my parents and grandparents.
Reading
1. In general, a blueprint is a drawing that shows how to put a house together with many different parts. 一般而言,蓝图就是一幅图纸, 它显示一座房子的构造。
in general = generally speaking 意思是“一般而言; 通常”
eg：In general/Generally speaking, women cry more easily than men. 一般而言, 女人比男人容易哭。
Language Points
2. But building a living thing is far more complex than building a house. 但创造一个生物比盖房子要复杂得多。
far用来修饰形容词和副词的比较级
[拓展] 这样的词语还有much, still, even, a little, a bit, a lot, rather等。
eg：The room is a bit larger than that one. 这个房间比那个稍大一点。
He works still harder than ever. 他比以往更加努力学习了。
Matters are a lot better than ever before. 情况远远比以往好。
Lesson One is much easier than Lesson Two.
第一课比第二课容易得多。
Tom looks even younger than before.
汤姆看上去甚至比以前还年轻。
This train runs much faster than that one. 这辆火车比那辆快得多。
3. Except for some twins, every living thing has its own unique DNA. 除了同卵双胞胎之外, 每个生物都有自己独特的DNA.
except for意思是“除······之外”,
eg: The city is good except for the weather.
除天气外,这座城市还不错。
[辨析] 各种各样的“除外”
except 意为 “除了”， 表示从整体中除去,不包括所除事物在内，除去的和非除去的是同类事物。一般不用于句首。
except for 意为 “除了”， 说明整个基本情况后，对细节加以纠正,其后一般接名词或名词性短语。
besides 意为 “除了……之外还有”，包括所 “除” 的事物在内。
but 意为 “除……外”， 多用在no, nobody, who, where, all等词之后。
eg：He is a good man except for a bad temper.
他是个好人，除了有点脾气坏 。
We all went to the zoo except Li Ming.
除了李明以外，我们都去了动物园。
Everyone was there but him. 除他之外，大家都在。
He also knows Japanese besides English.
除了懂英语之外，他也懂日语。（两门外语他都懂）
4. From your DNA, scientists can identify not only you, but also people who are related to you. 从你的DNA中,科学家们不但能够辨认出你,而且能够所认出和你有血缘关系的人。
not only...but also... “不但……而且……”连接两个并列主语时,谓语动词要与它最近的主语保持人称和数上的一致, 即“就近原则”
eg: Not only the boy but also his parents are staring at the screen.不但那个男孩而且他的父母也正在盯着屏幕。
relate与to/with连用, 表示“与……有关”或“使互相关联”
eg: The matter relates to him. 这事与他有关。
I can't relate what he does with what he says. 我无法把他的言行联系起来。
be related to “与……相关”
eg: He is related to my family. 他与我的家庭有关系。
5. Your DNA has billions of instructions that explain why you are the way you are. 你的DNA中有数十亿个指令, 来解释你为什么是现在这个样子。
billions of “数十亿计的; 大量”
[拓展] hundred, thousand, million, billion表示不确定的数目时用复数,而且要与of连用
eg：There are hundreds of books on the desk.
桌子上有几百本书.
句末的you are是the way的定语从句。way在本句中的意思是“情况;状态”。
eg：“How long has he been this way ” the doctor asked.
医生问:“他这种情况有多久了 ”
The business is in a poor way. 生意境况不佳。
② Fill in the blanks with the phrases in the box.
in general　 except for 　not only…but also
related to 　 even if　 the same…as
1．Your homework is quite good __________a few spelling mistakes.
2．________the young ________the old like pop music.
3．Kate’s hair is________ colour ______her sister's.
4．___________,women live longer than men.
5．________ many difficulties remain,we can overcome them.
6．Is wealth _________ happiness
Even if
related to
the same
In general　
except for
Not only
but also
as
What can scientists do with DNA
Thinking
③ Complete the passage with the sentences in the box.
A．Their DNA can't combine.
B．We can make plants that are bad for pests.
C．They can even combine the DNA of a plant and an animal.
Changing DNA
Do you know DNA can be changed Have you ever seen a pig with a dog's body Of course not! Pigs and dogs can't have babies together. ______ But now，scientists can do it. Scientists can take DNA , from one kind of animal and put it into another kind of animal. They can design new plants By combining the DNA of other plants.________ Some scientists are worried. They say we need to know more about DNA before we start changing it. ________ But what if the plants are bad for humans，too
A
C
B
④ Is it a good idea to change the DNA of the food we eat Some people say doing this makes our food better. Others think it’s too dangerous. Search the Internet for information and write down your ideas.
Divide the students into two groups.
One group support it is a good idea to change the DNA of the food we eat.
The other group say something about the disadvantages of changing the DNA of the food.
Show your opinion to the class.
Action
Words:
DNA, blueprint, twin, general, repeat, complex, pattern, identify, related, grandson, granddaughter, instruction
Sentences:
But building a living thing is far more complex than building a house.
Except for some twins, every living thing has its own unique DNA.
From your DNA, scientists can identify not only you, but also people who are related to you.
课堂总结
一、根据句意及首字母提示完成句子。
1. Mary and May are ______. They look the same.
2. Read the i_____________before using the new phone.
3. The company produces 　　　　 　(million) cars a year.
4. “　　　　 　 (总的来说), German cars are very good,” Danny said.
5. His heart attack could 　　　　 　　(与……相关的) his car accident last year.
nstructions
twins
millions of
In general
be related to
当堂检测
1. ________, it is not very bad to work in this factory.
A．General speak 　 B．Speaking generally
C．In general D．In generally
2. —Is Jack good at basketball
—Yes. He is also good at table tennis ________ basketball.
A．except B．besides C．but D．beside
3. —To achieve a bright future,we should ________ study hard ________ keep in good health.
—I agree with you.
A．not; but　　　 B．not only; but also
C．neither; nor D．either; or
二、单项选择
C
B
B