SharksareamongtheoldestanimalsonEarth.Therearehundredsofkindsofsharks.Mostareabouttwometerslong.Thedogfishsharkhoweverislessthantwentycentimetersinlength.Asharkhasanextremelygoodsenseofsmell.Itcanfindsmallamountsofmattersinwatersuchasbloodbodyliquidsandchemicalsproducedbyanimals.Thesepowerfulsenseshelpsharksfindtheirfood.Sharkseatfishothersharksandplantsthatliveintheocean.
Sharksgrowslowly.Aboutfortypercentofallsharkslayeggs.Theothersgivebirthtoliveyoung.Somesharkscarrytheiryounginsidetheirbodiesashumansdo.Somesharksarenotabletoreproduceuntiltheyaretwentyyearsold.Mostreproduceonlyeverytwoyears.Andtheygivebirthtofewerthantenyoungsharks.Forthisreasonover–fishingofsharksisofspecialdangertothefutureoftheanimal.
Sharksareimportantfortheworld’soceans.Theyeatinjuredanddiseasedfish.Theirhuntingactivitiesmeanthatthenumbersofotherfishinoceanwatersdonotbecometoogreat.Thisprotectstheplantsandotherformsoflifethatexistintheoceans.
Peoplehuntsharksforsportfoodmedicineandtheirskin.Expertssaytheinternationalmarketforsomekindsofsharkshasincreasedbecausemanypartsofasharkarevaluable.
Collectorspaythousandsofdollarsforthejawsofashark.SharkliveroilisapopularsourceofVitaminA.Theskinofasharkcanbeusedlikeleather.
InAsiapeopleenjoyakindofsoupmadefromsharkfins.Expertssayafishermancanearnalotofmoneyforevenonekilogramofsharkfins.SharksareamongtheoldestanimalsonEarthbutsomesharksareindangerofdisappearingfromEarth.Iftoomanysharksinoneareaarekilledthatgroupofsharksmayneverreturntonormalpopulationlevels.
1.Whichofthefollowingwordsbestdescribesthesituationsharksarein?
A.Good. B.Endangered. C.Powerful. D.Expensive.
2.Thepopulationofsharksisbecomingsmallerandsmallerasaresultof .
A.hunting B.lackoffood C.diseases D.theirpoorability
3.Sharkseatotherfish .
A.whichisathreattootherformsoflifeintheoceans
B.whichisaprotectionforotherformsoflifeintheo
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