C AMPBELL
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BIOLOGY
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Lisa A. Urry
j j MichaelL.Cain j j StevenA.Wasserman
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MILLS jCOLLEGE, NEW j MEXICO j STATE UNIVERSITY j OF j CALIFORNIA,
jUNIVERSITY
jOAKLAND, j CALIFORNIA jSAN j DIEGO
Rebecca B. Orr
Peter V. Minorsky
j j
j j
COLLIN j j j COLLEGE, j j j PLANO, j j j TEXAS
MERCY jCOLLEGE, j DOBBS
jFERRY, j NEW j YORK
,Director, jGlobal jHigher jEd jContent jManagement Project j Manager: j Katie j Cook
jand j Strategy, j Science j & j Health j Sciences: Content j Producers, j Mastering j Biology: j Kaitlin
j JeannejZalesky jSmith, j Ashley j Gordon
Manager, j Higher j Ed j Global j Content j Strategy, j Life Supervising j Media j Producer: j Tod j Regan
jSciences: j Joshua j Frost
Media jProducer: j j Ziki j jDekel
Associate j Content j j Analyst: j j Chelsea j j Noack Full-Service j Vendor: j Integra j Software j Services, j Inc.
Editorial j Assistant: j Ashley j Fallon Design jManager: j jMark j Ong
Director, jHigher jEd jProduct Cover j & jInterior j jDesigner: j jJeff j Puda
jManagement, j Life j Sciences: j Michael
Illustrators: j Lachina j Creative
jGillespie
Rights j & j Permissions j Project j Manager: j Matt j Perry,
Product j Manager: j Rebecca j Berardy j Schwartz jSPi j Global
Managing jProducer: j Michael j jEarly Rights j & j Permissions j Manager: j Ben j Ferrini
jSenior j Content j Producer: j Lori j Newman
Photo j Researcher: j Maureen j Spuhler
jDirector, j Content j Development j &
Product jand jSolutions jSpecialist: jKelly j jGalli
Partner j Relationships: j Ginnie
jSenior j Product j Marketing j Manager: j Alysun
Simione j Jutson
j Estes jManufacturing j Buyer: j Stacey j Weinberger,
Supervising j Editors: j Beth j N. j Winickoff, j Pat j Burner
j LSC
Senior j Developmental j Editors: j John jBurner, j Mary j Ann
Communications
jMurray, j Hilair j Chism, j Andrew j Recher, jMary j Hill
Cover jPhoto j Credit: j Robert jRohrbaugh/Rohrbaugh
Specialist, j Instructional j j j Design j j j and j j j Development:
jPhotography
Sarah jYoung-Dualan
Senior j Content j j j Developer, j j j Mastering j j j Biology:
Sarah j Jensen
Copyright j© j2021, j2017, j2014 jby jPearson jEducation, j jInc. j jor j jits j jaffiliates, j j221 j jRiver j jStreet, j jHoboken, j jNJ
j07030. j All j Rights j Reserved. j Manufactured j in j the j United j States j of j America. j This j publication j is
j protected j by jcopyright, jand jpermission jshould jbe jobtained jfrom j jthe j jpublisher j jprior j jto j jany j jprohibited j
jreproduction, jstorage jin ja jretrieval jsystem, jor jtransmission jin jany jform jor jby jany j jmeans, j jelectronic, j
jmechanical, jphotocopying, j recording, j or otherwise. jFor jinformation jregarding jpermissions, jrequest jforms, jand
jthe jappropriate jcontacts jwithin jthe jPearson jEducation jGlobal jRights jand jPermissions jdepartment, jplease jvisit
jwww.pearsoned.com/permissions/.
Acknowledgments j of j third-party j content j appear j in j the j Credits j section j (beginning j on j page j CR-1), j which
jconstitutes j an j extension j of j this j copyright j page.
PEARSON, j ALWAYS j LEARNING, j MasteringTM j j Biology, jand jBioFlix® jare jexclusive jtrademarks jowned jby
jPearson j Education, j Inc. j or j its j affiliates j in j the j U.S. j and/or j other j countries.
Unless j otherwise j indicated j herein, j any j third-party j trademarks j that j may j appear j in j this j work j are j the
j property jof jtheir jrespective jowners jand jany jreferences jto jthird-party jtrademarks, jlogos jor jother jtrade jdress jare
jfor jdemonstrative jor jdescriptive jpurposes jonly. jSuch jreferences jare jnot jintended jto jimply jany jsponsorship,
jendorsement, jauthorization, jor jpromotion jof jPearson’s jproducts jby jthe jowners jof j jsuch j jmarks, j jor j jany
jrelationship jbetween j jthe j jowner j jand j jPearson j jEducation, j jInc. j jor j jits j jaffiliates, j jauthors, j jlicensees j jor
jdistributors.
Library j of j Congress j Cataloging-in-Publication j Data
Names: jUrry, jLisa jA., jauthor. j| jCain, j jMichael j jL. j j(Michael j jLee),
jauthor. j| j Wasserman, j Steven jAlexander, j author. j j| j jMinorsky,
jPeter jV., jauthor. j| jOrr, j Rebecca jB., jauthor. j| jCampbell, j Neil j A.,
jBiology.
Title: j Campbell j biology j / j Lisa j A. j Urry, j Michael j L. j Cain, j Steven
A. jWasserman, jPeter jV. jMinorsky, j Rebecca j B. j Orr, j Neil j A.
jCampbell.
Description: jTwelfth jedition. j| jNew jYork, jNY j j: j Pearson, j 2020. j j| j jIncludes
jindex. j Identifiers: j LCCN j 2019039139 j | j ISBN j 9780135188743 j (hardcover)
|
ISBN j 9780135988046 j (ebook)
Subjects: j LCSH: j j j Biology.
Classification: jLCC jQH308.2 j.C34 j2020 j| jDDC j j570—
jdc23 LC record available at
jhttps://lccn.loc.gov/2019039139
ScoutAutomatedPrintCode
, ISBN j 10: j 0-135-18874-1; j ISBN j 13: j 978-0-135-18874-3 j (Rental j Edition)
ISBN j 10: j 0-136-62344-1; j ISBN j 13: j 978-0-136-62344-1 j (Instructor j Review j Copy)
www.pearson.com
, Setting the Standard for Excellence,
h h h h
Accuracy, and Innovation
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Campbell Biology, 12th Edition, delivers an authoritative, accurate, current,
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and pedagogically innovative experience that helps students make connections
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so they learn and understand biology. This edition presents new, engaging
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visual and digital resources that meet demonstrated student needs.
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h j j j j j j j h
BIOLOGY
h h
TW ELF TH
j j j j
h
j j j
h
h jh j EDITI O N
j j j j j
h
j j h
h
Lisa A. Urry
j j MichaelL.Cain j j StevenA.Wasserman
j j
MILLS jCOLLEGE, NEW j MEXICO j STATE UNIVERSITY j OF j CALIFORNIA,
jUNIVERSITY
jOAKLAND, j CALIFORNIA jSAN j DIEGO
Rebecca B. Orr
Peter V. Minorsky
j j
j j
COLLIN j j j COLLEGE, j j j PLANO, j j j TEXAS
MERCY jCOLLEGE, j DOBBS
jFERRY, j NEW j YORK
,Director, jGlobal jHigher jEd jContent jManagement Project j Manager: j Katie j Cook
jand j Strategy, j Science j & j Health j Sciences: Content j Producers, j Mastering j Biology: j Kaitlin
j JeannejZalesky jSmith, j Ashley j Gordon
Manager, j Higher j Ed j Global j Content j Strategy, j Life Supervising j Media j Producer: j Tod j Regan
jSciences: j Joshua j Frost
Media jProducer: j j Ziki j jDekel
Associate j Content j j Analyst: j j Chelsea j j Noack Full-Service j Vendor: j Integra j Software j Services, j Inc.
Editorial j Assistant: j Ashley j Fallon Design jManager: j jMark j Ong
Director, jHigher jEd jProduct Cover j & jInterior j jDesigner: j jJeff j Puda
jManagement, j Life j Sciences: j Michael
Illustrators: j Lachina j Creative
jGillespie
Rights j & j Permissions j Project j Manager: j Matt j Perry,
Product j Manager: j Rebecca j Berardy j Schwartz jSPi j Global
Managing jProducer: j Michael j jEarly Rights j & j Permissions j Manager: j Ben j Ferrini
jSenior j Content j Producer: j Lori j Newman
Photo j Researcher: j Maureen j Spuhler
jDirector, j Content j Development j &
Product jand jSolutions jSpecialist: jKelly j jGalli
Partner j Relationships: j Ginnie
jSenior j Product j Marketing j Manager: j Alysun
Simione j Jutson
j Estes jManufacturing j Buyer: j Stacey j Weinberger,
Supervising j Editors: j Beth j N. j Winickoff, j Pat j Burner
j LSC
Senior j Developmental j Editors: j John jBurner, j Mary j Ann
Communications
jMurray, j Hilair j Chism, j Andrew j Recher, jMary j Hill
Cover jPhoto j Credit: j Robert jRohrbaugh/Rohrbaugh
Specialist, j Instructional j j j Design j j j and j j j Development:
jPhotography
Sarah jYoung-Dualan
Senior j Content j j j Developer, j j j Mastering j j j Biology:
Sarah j Jensen
Copyright j© j2021, j2017, j2014 jby jPearson jEducation, j jInc. j jor j jits j jaffiliates, j j221 j jRiver j jStreet, j jHoboken, j jNJ
j07030. j All j Rights j Reserved. j Manufactured j in j the j United j States j of j America. j This j publication j is
j protected j by jcopyright, jand jpermission jshould jbe jobtained jfrom j jthe j jpublisher j jprior j jto j jany j jprohibited j
jreproduction, jstorage jin ja jretrieval jsystem, jor jtransmission jin jany jform jor jby jany j jmeans, j jelectronic, j
jmechanical, jphotocopying, j recording, j or otherwise. jFor jinformation jregarding jpermissions, jrequest jforms, jand
jthe jappropriate jcontacts jwithin jthe jPearson jEducation jGlobal jRights jand jPermissions jdepartment, jplease jvisit
jwww.pearsoned.com/permissions/.
Acknowledgments j of j third-party j content j appear j in j the j Credits j section j (beginning j on j page j CR-1), j which
jconstitutes j an j extension j of j this j copyright j page.
PEARSON, j ALWAYS j LEARNING, j MasteringTM j j Biology, jand jBioFlix® jare jexclusive jtrademarks jowned jby
jPearson j Education, j Inc. j or j its j affiliates j in j the j U.S. j and/or j other j countries.
Unless j otherwise j indicated j herein, j any j third-party j trademarks j that j may j appear j in j this j work j are j the
j property jof jtheir jrespective jowners jand jany jreferences jto jthird-party jtrademarks, jlogos jor jother jtrade jdress jare
jfor jdemonstrative jor jdescriptive jpurposes jonly. jSuch jreferences jare jnot jintended jto jimply jany jsponsorship,
jendorsement, jauthorization, jor jpromotion jof jPearson’s jproducts jby jthe jowners jof j jsuch j jmarks, j jor j jany
jrelationship jbetween j jthe j jowner j jand j jPearson j jEducation, j jInc. j jor j jits j jaffiliates, j jauthors, j jlicensees j jor
jdistributors.
Library j of j Congress j Cataloging-in-Publication j Data
Names: jUrry, jLisa jA., jauthor. j| jCain, j jMichael j jL. j j(Michael j jLee),
jauthor. j| j Wasserman, j Steven jAlexander, j author. j j| j jMinorsky,
jPeter jV., jauthor. j| jOrr, j Rebecca jB., jauthor. j| jCampbell, j Neil j A.,
jBiology.
Title: j Campbell j biology j / j Lisa j A. j Urry, j Michael j L. j Cain, j Steven
A. jWasserman, jPeter jV. jMinorsky, j Rebecca j B. j Orr, j Neil j A.
jCampbell.
Description: jTwelfth jedition. j| jNew jYork, jNY j j: j Pearson, j 2020. j j| j jIncludes
jindex. j Identifiers: j LCCN j 2019039139 j | j ISBN j 9780135188743 j (hardcover)
|
ISBN j 9780135988046 j (ebook)
Subjects: j LCSH: j j j Biology.
Classification: jLCC jQH308.2 j.C34 j2020 j| jDDC j j570—
jdc23 LC record available at
jhttps://lccn.loc.gov/2019039139
ScoutAutomatedPrintCode
, ISBN j 10: j 0-135-18874-1; j ISBN j 13: j 978-0-135-18874-3 j (Rental j Edition)
ISBN j 10: j 0-136-62344-1; j ISBN j 13: j 978-0-136-62344-1 j (Instructor j Review j Copy)
www.pearson.com
, Setting the Standard for Excellence,
h h h h
Accuracy, and Innovation
jh h h
Campbell Biology, 12th Edition, delivers an authoritative, accurate, current,
h h h h h h h h
and pedagogically innovative experience that helps students make connections
jh h h h h h h h h
so they learn and understand biology. This edition presents new, engaging
jh h h h h h h h h h h
visual and digital resources that meet demonstrated student needs.
jh h h h h h h h h
