1、(tl)NASA/Science Photo Library/Photo Researchers,(tr)Billy&Sally Fletcher/Tom Stack&Assoc.,(b)Photodisc i-01-LBJ-861761 08/16/2004 1:43 PM Page iAstronomyThis collection of images is ofJupiter,Io(one of its moons),Mars,and the AndromedaGalaxy.The AndromedaGalaxy is the most distantobject visible to
2、the humaneye.At a distance of 2.2 mil-lion light years,it appears as afuzzy patch of light in thenight sky.Send all inquiries to:Glencoe/McGraw-Hill8787 Orion PlaceColumbus,OH 43240-4027ISBN:0-07-861761-8Printed in the United States of America.2 3 4 5 6 7 8 9 10 027/043 09 08 07 06 05 04Copyright 20
3、05 by The McGraw-Hill Companies,Inc.All rights reserved.Except as permitted underthe United 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 N
4、ational Geographic features were designed and developed by the National Geographic SocietysEducation 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 stri
5、ctly prohibited.The“Science and Society”and the“Science and History”features that appear 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.(tl)NASA/Science Photo Library/Photo Researcher
6、s,(tr)Billy&Sally Fletcher/Tom Stack&Assoc.,(b)Photodisc i-01-LBJ-861761 08/16/2004 1:43 PM Page iiCONTENTWilliam C.Keel,PhDDepartment of Physics and AstronomyUniversity of Alabama Tuscaloosa,ALMATHTeri Willard,EdDMathematics Curriculum WriterBelgrade,MTREADINGCarol A.Senf,PhDSchool of Literature,Co
7、mmunication,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 TESTERSMary Helen Mariscal-CholkaWilliam D.Slider Middle SchoolEl Pa
8、so,TXScience Kit and Boreal LaboratoriesTonawanda,NYJiiiAuthorsSeries ConsultantsMary FerneauWestview Middle SchoolGoose Creek,SCAnnette DUrso GarciaKearney Middle SchoolCommerce City,CONerma Coats HendersonPickerington Lakeview Jr.High SchoolPickerington,OHMichael MansourBoard MemberNational Middle
9、 Level Science Teachers AssociationJohn Page Middle SchoolMadison Heights,MIMary Helen Mariscal-CholkaWilliam D.Slider Middle SchoolEl Paso,TXSharon MitchellWilliam D.Slider Middle SchoolEl Paso,TXSeries ReviewersEducation DivisionWashington,D.C.Ralph M.Feather Jr.,PhDScience Department ChairDerry A
10、rea School DistrictDerry,PADinah ZikeEducational ConsultantDinah-Might Activities,Inc.San Antonio,TX i-01-LBJ-861761 08/16/2004 1:43 PM 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 st
11、uck on how to answer aquestion?Maybe you just wondered when you were evergoing to use this stuff?These 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 openin
12、g photo of each chapter will preview thescience you will be learning about.The ChapterPreview will give 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 Op
13、enerChapters are divided into two to foursections.The As You Read in the margin of the firstpage of 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 youw
14、hy you are studying this in the first place!TheReview Vocabulary word is a word you already know,either 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 thes
15、ection.Make a note to yourself to recognize thesewords as you are reading the section.(bkgd)John Evans,(inset)(tl)NASA/Science Photo Library/Photo Researchers,(tr)Billy&Sally Fletcher/Tom Stack&Assoc.,(b)Photodisc i-01-LBJ-861761 08/16/2004 1:43 PM Page ivAs You ReadHeadingsEach section has a titlei
16、n 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 concepts you have learned.Building SkillsYou also will find anApplying Math or Applying Science activityin each chapter.