ExpositoryTextThreatsOceanPAIREDREADFloatingTrashbyKenBennSTRATEGIES&SKILLSPhotographyCredit:DigitalVision/GettyImages**Thetotalwordcountisbasedonwordsintherunningtextandheadingsonly.Numeralsandwordsincaptions,labels,diagrams,charts,andsidebarsarenotincluded.AWordCount:2,020**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:978-0-02-119248-9MHID:0-02-119248-0PrintedintheUnitedStates.123456789DOC151413121110PAIREDREADEssentialQuestionWhatchangesintheenvironmentaffectlivingthings?Introduction..................................2Chapter1WhatAreAlgae?..............................4Chapter2WhatCausesAlgalBlooms?....................8Chapter3WhyShouldWeBeConcerned?...............12Conclusion...................................16RespondtoReading..........................18FloatingTrash.....................19Glossary.....................................22Index........................................23FocusonScience....................24byKenBennThreatsOceanIntroductionDidyouknowthatnearlythree-quartersofourplanetiscoveredinwater?Earth’srivers,lakes,andoceanssupportmanylivingorganisms.Algaearesomeofthemostwidespreadoftheselifeforms,whichalsoincludeplantsandanimals.Algaearesimpleplant-likeorganismsfoundallovertheplanet.Theycanvaryinsizefromtinyplanktontohugeseaweedmorethan200feetlong.Manyalgaeareharmlessandposenothreattohumansortheenvironment,butotherscanbedeadly.Theycanthreatenhumanandanimallife.Iftheirpopulationgrowstoon...
