高二英语师大选择性必修一-Unit-3-Conservation-1课件.pptx

1、北京市中小学空中课堂选择性必修一 Unit 3 Conservation(1)高二年级 英语The Sixth ExtinctionReading(1)Activate and shareextinctionActivate and share1.What is extinction?Extinction is a situation in which something no longer exists.dinosaurActivate and share2.How much do you know about extinction?How many times up to today ha

2、s life on Earth almost died out?A.Once.B.Five times.C.More than 10 times.Activate and share About which percent of all species on Earth became extinct during the mass extinction known as the“Great Dying”?A.Less than 10%.B.Nearly 50%.C.More than 90%.Activate and share What do scientists think will ca

3、use the next mass extinction?A.Human activity.B.Natural causes.C.Unknown reasons.Read and explore 1.Read the passage and finish the two tasks:Check whether your answers in the quiz are right.Get the main idea of each paragraph.Read and explore Check the answers in the quiz.How many times up to today

4、 has life on Earth almost died out?A.Once.B.Five times.C.More than 10 times.Read and explore About which percent of all species on Earth became extinct during the mass extinction known as the“Great Dying”?A.Less than 10%.B.Nearly 50%.C.More than 90%.What do scientists think will cause the next mass

5、extinction?A.Human activity.B.Natural causes.C.Unknown reasons.Read and exploreGet the main idea of each paragraph.Para.1:Para.2:Para.3:Para.4:Background history of the sixth extinctionCauses of the sixth extinctionEffects of the sixth extinctionWhat we can do to prevent the sixth extinction Read an

6、d exploreBackground historyCausesEffectsSolutionsTheSixthExtinctionDevelopment of the passageRead and explore2.Read the passage again and complete the notes.Meaning of extinction:ExtinctionThe number of extinctions that have occurred so far:Two notable extinctions and their consequences:Main reasons

7、 that cause extinctions:How to avoid the sixth mass extinction:Read and exploreMeaning of extinction:Extinctionentire species are wiped outRead and exploreExtinctionThe number of extinctions that have occurred so far:over 90%of all species that ever livedRead and exploreExtinctionTwo notable extinct

8、ions and their consequences:the third mass extinction killed 90%to 96%of all species;the fifth event,which occurred 66 million years ago,caused the death of dinosaurs.Read and exploreExtinctionMain reasons that cause extinctions:volcanic eruptions,asteroids hitting the Earth from space,changes in se

9、a levels,the decrease of oxygen content of the sea,global warmingRead and exploreExtinctionHow to avoid the sixth mass extinction:change the way we live,including setting up special areas where plants and animals can be protected;change how we work and travel by using cleaner,more natural sources of

10、 energy;improve our farming methodsRead and exploreRetell this part of the passage according to your notes.Meaning of extinction:ExtinctionThe number of extinctions that have occurred so far:Two notable extinctions and their consequences:Main reasons that cause extinctions:How to avoid the sixth mas

11、s extinction:Read and exploreRetelling Extinction means the entire species are wiped out.So far over 90%of all species that ever lived are extinct.Along the history,there are 2 notable extinctions,the third one and the fifth one.During the third mass extinction,known as the“Great Dying”,90%to 96%of

12、all species died out.The fifth one,which occurred 66 million years ago,caused the death of dinosaurs.Read and exploreRetelling There are many reasons that cause extinctions,such as volcanic eruptions,asteroids hitting the Earth from space,changes in sea levels,the decrease of oxygen content of the s

13、ea and global warming.Read and exploreRetelling The good news is that we can do something to avoid the sixth mass extinction.Firstly,we have to significantly change the way we live.We need to take steps to save endangered species,including setting up special areas where plants and animals can be pro

14、tected.Also,we can change how we work and travel by using cleaner and more natural sources of energy,such as wind and solar energy.We also need to improve our farming methods.Read and explore3.Read the passage again and answer the questions.What did scientists find out in 2015?Why does the writer th

15、ink the sixth mass extinction will come?Why does the writer believe well probably die out if 75%of the Earths species die out?What did people do in the case study to protect black robins?Which claim(s)did the study support in the text?Read and explore What did scientists find out in 2015?The study l

16、ooked at how quickly species die out due to natural causes,that is,the“background extinction rate”.They found that human activity is causing species to die out 1,000 times faster than normal.Read and explore Why does the writer think the sixth mass extinction will come?Because human activity has neg

17、atively affected all other species on Earth,including animals and plants.Read and explore Why does the writer believe well probably die out if 75%of the Earths species die out?Because our world and our lives depend on the balance in nature between animals and plants.Read and explore What did people

18、do in the case study to protect black robins?Which claim(s)did the study support in the text?People protected Old Blues eggs,helped them to hatch,and took care of the chicks.People are restoring their habitats and removing pests like mice and cats from the islands where they live.What we can do to p

19、revent the sixth extinctionRead and exploreCausesEffectsAn example of protectionTheSixthExtinctionRetell this part of the passage.Read and explore The study in 2015 found that human activity is causing species to die out 1,000 times faster than normal.It is clear that human activity has negatively a

20、ffected all other species on Earth,including animals and plants.RetellingRead and exploreRetellingThere is no doubt that our world and our lives depend on the balance in nature between animals and plants.If 75%of the Earths species disappear,we human beings will also face the risk of dying out.Read

21、and exploreRetelling The good news is that people are doing something to protect animals and plants on Earth.For example,people are taking measures to protect an endangered bird called Old Blue.Through our efforts,the number of this bird is increasing steadily.Therefore,you see,we can do something t

22、o help the earth and its never too late to act.Think and shareAs a student,what do you think you can do to help the Earth?l reduce wastel put rubbish into separate dustbinsl cycle or take public transportationl use fewer plastic bags while going shoppingSummaryBackground historyCausesEffectsSolutionsTheSixthExtinctionHomework 1.Read the passage aloud.2.Write a short passage about the sixth extinction.Thank you!