高中英語必修三第四單元PPT幻燈片課件

Unit4 Astronomy thescienceofthestars 1 Howmuchdoyouknowabouttheuniverse Whatarethenamesoftheeightplanetsthatcircleoursun Whatistheirorderfromthesun 2 3 地球 木星 火星 水星 海王星 土星 天王星 金星 Earth Jupiter Mars Mercury Neptune Saturn Uranus Venus 4 1 Howoldistheuniverse 2 Howoldistheearth 3 Whichwerethefirstcreatureorplantsonearth 4 Doyouknowwhattheorderforthedevelopmentofplantsandanimalsis Severalbillionyearsago Between4 5and3 8billionyearsago Verysmallair breathingcreatures FreeTalk 5 Ideasabouthowlifebegan 6 reading HowLifeBeganontheEarth 7 Fastreading Readthepassagequicklyandfindthemainidea Abriefintroductiononhowtheuniversedevelopedandhowlifebeganontheearth 8 Carefulreading Para1 Para2 Para3 Para4 Para5 Awidelyacceptedtheoryabouttheformationoftheuniverse Theformationoftheearth Theimportanceofwaterforlife Thedevelopmentofplantsandanimalsontheearth Thearrivalofhumansandtheirimpactontheearth Readthepassagecarefullyandanalyseitsstructure earth atmosphereandwater lifedevelopment humanbeings 9 1 Whatistheoriginalearth satmospheremadeupof 2 Whydidscientistsbelievewaterisfundamentaltothedevelopmentoflife 3 Howdidwatercomeintobeingontheearth 4 Whichkindoflife beingfirstappearedontheearth plantsoranimals Why 5 Whyweremammalsdifferentfromalllifeformsinthepast Answerthefollowingquestions 10 Carbon nitrogen watervapour andothergases 2 Whydidscientistbelievewaterisfundamentaltothedevelopmentoflife Becausewaterallowedtheearthtodissolveharmfulgasesandacidsintotheoceansandseastoensureafollowingchainreaction whichmadeitpossibleforlifetodevelop Whatistheoriginalearth satmospheremadeupof 3 Howdidwatercomeintobeingontheearth Theexplosionoftheearthproducedwatervapor whichturnedintowaterwhentheearthcooleddown 11 4 Whichkindoflife beingfirstappearedontheearth plantsoranimals Why Atfirst smallplantsbegantoappearonthesurfaceofthewater theyproduceoxygen whichencouragedthelaterdevelopmentofearlyshellfishandallsortsoffish 5 Whyweremammalsdifferentfromalllifeformsinthepast Theyweredifferentbecausetheyproducedtheiryoungfromwithintheirbodiesandproducemilktofeedthem 12 1Insectsandamphibiansappeared 2Dinosaursappeared 3Theearthbecameasolidball 4Smallplantsgrewonthewater 5Reptilesappeared 6Plantsbegantogrowondryland 7Theearthwasacloudofdust 8Waterappearedontheearth 9Shellfishandotherfishappeared 10Theuniversebeganwitha BigBang 11Cleveranimalswithhandsandfeetappeared 12Mammalsappeared 8 7 5 6 4 1 10 3 9 2 Puttheorderofdevelopmentoflife 12 11 13 Letreviewtheevolutionoflifeontheearth 14 Afterthe BigBang theearthwasfullofwater 15 Originalcellsappearedintheocean 16 Thecellsinthewaterbegantoseparate Smallplantscameintobeing 17 Earlyshellfishandallsortsoffish 18 Someanimals amphibian insects cametoland 19 Reptileappeared 20 dinosaurs 21 mammals 22 Manhadevolvedfromapes 23 Wearemakingtheworldbetter Wearemakingtheworldworse Discussion 24 Becausetheyareputtingtoomuchcarbondioxideintotheatmosphere Theearthmaybecometoohottoliveon 25 Theearthisbecominghotterandhotter 26 solarenergy planttrees recyclerubbish preventdesertification savewater purifyair Whatcanwedototakecareoftheearth 27 Whetherlifewillcontinueontheearthdependsonhumanbeings 28 精講點(diǎn)撥 Theearthbecamesoviolentthatitwasnotclearwhethertheshapewouldlastornot Whatmanyscientistsbelieveisthatthecontinuedpresenceofwaterallowedtheearthtodissolveh