ExpositoryTextThreatsOceanPAIREDREADFloatingTrashbyKenBennSTRATEGIES&SKILLSPhotographyCredit:DigitalVision/GettyImages**Thetotalwordcountisbasedonwordsintherunningtextandheadingsonly.Numeralsandwordsincaptions,labels,diagrams,charts,andsidebarsarenotincluded.AWordCount:1,472**ComprehensionStrategy:AskandAnswerQuestionsSkill:CompareandContrastVocabularyStrategyParagraphCluesVocabularyatmosphere,decay,gradual,impact,noticeably,receding,stability,variationsContentStandardsScienceEarthandSpaceScienceCopyright©TheMcGraw-HillCompanies,Inc.Allrightsreserved.Nopartofthispublicationmaybereproducedordistributedinanyformorbyanymeans,orstoredinadatabaseorretrievalsystem,withoutthepriorwrittenconsentofTheMcGraw-HillCompanies,Inc.,including,butnotlimitedto,networkstorageortransmission,orbroadcastfordistancelearning.Sendallinquiriesto:McGraw-HillEducationTwoPennPlazaNewYork,NewYork10121ISBN:978-0-02-119197-0MHID:0-02-119197-2PrintedintheUnitedStates.123456789DOC151413121110PAIREDREADEssentialQuestionWhatchangesintheenvironmentaffectlivingthings?Introduction...............................2Chapter1WhatAreAlgae?...........................4Chapter2WhatCausesAlgalBlooms?.................8Chapter3WhyShouldWeBeConcerned?............12Conclusion................................16RespondtoReading.......................18FloatingTrash...................19Glossary..................................22Index.....................................23FocusonScience..................24byKenBennThreatsOceanIntroductionAlgaearesimpleplant-likeorganismsthatusuallyliveinwater.Theycanbefoundineverypartoftheworld.Algaevaryinsize.Somealgaearetinyplankton,andsomearehugeseaweedsthataremorethan200feetlong.Manytypesofalgaeareharmless,butsomealgaecanbedangeroustohumansandanimals.Ifthealgaepopulationinanareagetstoolarge,thealgaecanchangethatareasothatnothingelsecanlivethere.2DonJohnston/agefotostock/GettyImagesSometimeschangesinanenvironmentfavoralgae.Verylargepopulationsofalgaearecalled“algalblooms.”Algalblo...
