1、Jack Dykinga/Getty Imagesi-01-LBG-861752 8/23/04 11:18 AM Page iThe ChangingSurface of EarthFly Geyser,Nevada is ahuman-made drill well,whichis now a constantly spoutinghotspring.It is located in theBlack Rock Desert,near Gerlach,Nevada.The tufa terraces,or“natural steps,”are formed bymineral deposi
2、ts from thesprings.Send all inquiries to:Glencoe/McGraw-Hill8787 Orion PlaceColumbus,OH 43240-4027ISBN:0-07-861752-9Printed in the United States of America.2 3 4 5 6 7 8 9 10 027/043 09 08 07 06 05 04Copyright 2005 by The McGraw-Hill Companies,Inc.All rights reserved.Except as permitted underthe Uni
3、ted States Copyright Act,no part of this publication may be reproduced or distributed in anyform or by any means,or stored in a database or retrieval system,without prior written permission of the publisher.The National Geographic features were designed and developed by the National Geographic Socie
4、tysEducation Division.Copyright National Geographic Society.The name“National Geographic Society”and the Yellow Border Rectangle are trademarks of the Society,and their use,without prior writtenpermission,is strictly prohibited.The“Science and Society”and the“Science and History”features that appear
5、 in this book weredesigned and developed by TIME School Publishing,a division of TIME Magazine.TIME and the redborder are trademarks of Time Inc.All rights reserved.Jack Dykinga/Getty Imagesi-01-LBG-861752 8/23/04 11:18 AM Page iiCONTENTWilliam C.Keel,PhDDepartment of Physics andAstronomyUniversity
6、of Alabama Tuscaloosa,ALRobert NiersteScience Department HeadHendrick Middle School,Plano ISDPlano,TXMATHMichael Hopper,DEngManager of Aircraft Certification L-3 CommunicationsGreenville,TXTeri Willard,EdDMathematics Curriculum WriterBelgrade,MTREADINGCarol A.Senf,PhDSchool of Literature,Communicati
7、on,and CultureGeorgia Institute of TechnologyAtlanta,GASAFETYAileen Duc,PhDScience 8 TeacherHendrick Middle School,Plano ISDPlano,TXSandra West,PhDDepartment of BiologyTexas State University-San MarcosSan Marcos,TXACTIVITY TESTERSNerma Coats HendersonPickerington Lakeview Jr.HighSchoolPickerington,O
8、HMary Helen Mariscal-CholkaWilliam D.Slider Middle SchoolEl Paso,TXScience Kit and BorealLaboratoriesTonawanda,NYGiiiAuthorsSeries ConsultantsLois BurdetteGreen Bank Elementary-MiddleSchoolGreen Bank,WVMarcia ChackanPine Crest SchoolBoca Raton,FLKaren CurryEast Wake Middle School Raleigh,NC Annette
9、DUrso GarciaKearney Middle SchoolCommerce City,CONerma Coats HendersonPickerington Lakeview Jr.HighSchoolPickerington,OHMichael MansourBoard MemberNational Middle Level ScienceTeachers AssociationJohn Page Middle SchoolMadison Heights,MISharon MitchellWilliam D.Slider Middle SchoolEl Paso,TXSeries R
10、eviewersEducation DivisionWashington,D.C.Ralph M.Feather Jr.,PhDAssistant Professor Geoscience DepartmentIndiana University of PennsylvaniaIndiana,PASusan Leach SnyderRetired Teacher/ConsultantJones Middle SchoolUpper Arlington,OHDinah ZikeEducational ConsultantDinah-Might Activities,Inc.San Antonio
11、,TXi-01-LBG-861752 8/23/04 11:18 AM Page iiiWhy do I need my science book?Have you ever been in class andnot understood all of what waspresented?Or,you understoodeverything in class,but at home,got stuck on how to answer aquestion?Maybe you just wondered when you were evergoing to use this stuff?The
12、se next few pages are designed to help you understand everything your science book can be used for.besides a paperweight!Before You ReadChapter OpenerScience is occurring all around you,and the opening photo of each chapter will preview thescience you will be learning about.The ChapterPreview will g
13、ive you an idea of what you will belearning about,and you can try the Launch Lab tohelp get your brain headed in the right direction.TheFoldables exercise is a fun way to keep you organized.Section OpenerChapters are divided into two to foursections.The As You Read in the margin of the firstpage of
14、each section will let you know what is mostimportant in the section.It is divided into four parts.What Youll Learn will tell you the major topics youwill be covering.Why Its Important will remind youwhy you are studying this in the first place!TheReview Vocabulary word is a word you already know,eit
15、her from your science studies or your prior knowl-edge.The New Vocabulary words are words that youneed to learn to understand this section.These wordswill be in boldfaced print and highlighted in thesection.Make a note to yourself to recognize thesewords as you are reading the section.(bkgd)John Eva
16、ns,(inset)Jack Dykinga/Getty Imagesi-01-LBG-861752 8/23/04 11:18 AM Page ivAs You ReadHeadingsEach section has a titlein large red letters,and is furtherdivided into blue titles andsmall red titles at the begin-nings of some paragraphs.To help you study,make anoutline of the headings andsubheadings.MarginsIn the margins ofyour text,you will find many helpfulresources.The Science Online exercises andIntegrate activities help you explore the topicsyou are studying.MiniLabs reinforce the sci-ence c
