Lesson 29 DNA—The Story of You 表格式教案 冀教版英语九年级全册

教学课题 Lesson 29　DNA—The Story of You 备注 教学目标 【知识目标】 Important words: DNA,blueprint,general,complex,twin,repeat,pattern,identify,related,grandson,granddaughter,instruction Important phrases:in general,except for,be related to,billions of Important sentences: (1)In general,a blueprint is a drawing that shows how to put a house together with many different parts. (2)But building a living thing is far more complex than building a house. (3)Except for some twins,every living thing has its own unique DNA. (4)From your DNA,scientists can identify not only you,but also people who are related to you. (5)Your DNA has billions of instructions that explain why you are the way you are. 【能力目标】 能够用英语向他人介绍自己所知道的有关DNA的知识。 【情感目标】 了解有关DNA的奥秘。 教学 重难点 重点:本课重点单词及短语。 难点:except,except for 与 besides 的用法辨析。 教学过程 ◆Step 1　Lead in Show students the picture on PPT. T:Do they look the same S:Yes,they do. T:They're twins.Do you know why they are the same S:Because they have the same DNA. T:Do you look like your mother or your father S:My mother/father. T:Do you know the reason Because your DNA comes from your parents.This is the shape of DNA.What is DNA DNA is short for deoxyribonucleic acid(脱氧核糖核酸).The function of DNA is to store genetic information. 设计意图:通过询问本节课相关问题,引出本课话题———DNA,为下面的学习奠定基础。 与学生进行一个简短的对话,进入本课主题。 ◆Step 2　Think about it. What can scientists do with DNA ◆Step 3　Show learning aims. Let the students read the learning aims together.(见课件) ◆Step 4　Learn the new words and expressions. 设计意图:让学生在学习本课时之前,了解本节课的学习目标以及需掌握的单词短语。 ◆Step 5　Listening Listen to the lesson and finish the exercises. 1.Where does your DNA come from 2.Is your DNA in every part of your body 3.Generally speaking,a 　　　 is a drawing. 4.　　　 for identical twins,each living thing has its own unique DNA. 【Keys】1.My parents.　2.Yes,it is.　3.blueprint　4.Except 设计意图:通过听听力做练习,提高听力水平,并大体了解课文内容。 ◆Step 6　Reading Read the lesson and answer the questions.(见课本P75 Let's do it!1) 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 do you have 【Keys】 1.A blueprint is a drawing that shows how to put a house together with many different parts. 2.Building a living thing is far more complex than building a house. 3.Yes,they do. 4.Yes,it is.In the future,scientists might be able to change our DNA. 5.The DNA of my parents and grandparents. 设计意图:要求学生认真阅读课文,把握课文信息,回答问题,对文章内容有更深层次的理解。 ◆Step 7　Language points 1.in general意为“一般而言,概括说来”,通常置于句首,也可以用generally speaking来表示。 2.different为形容词,意为“不同的”,常用于以下结构中:be different from与……不同;be different in...在……上不同。 3.比较级前可以用much,even,still ... ...