Understanding Biology

1089 Pages·2017·194.016 MB·English

by  Kenneth Mason et al.

Understanding
Biology
Second Edition
Kenneth A. Mason
University of Iowa
Tod Duncan
University of Colorado Denver
George B. Johnson
Professor Emeritus of Biology
Washington University
Jonathan B. Losos
Harvard University
Susan R. Singer
Carleton College
mas92413_fm_i-xxiv.indd 1 28/11/16 12:26 pm
UNDERSTANDING BIOLOGY, SECOND EDITION
Published by McGraw-Hill Education, 2 Penn Plaza, New York, NY 10121. Copyright © 2018 by McGraw-Hill
Education. All rights reserved. Printed in the United States of America. Previous edition © 2015. No part of this
publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval
system, without the prior written consent of McGraw-Hill Education, including, but not limited to, in any network
or other electronic storage or transmission, or broadcast for distance learning.
Some ancillaries, including electronic and print components, may not be available to customers outside
the United States.
This book is printed on acid-free paper.
1 2 3 4 5 6 7 8 9 LWI 21 20 19 18 17
ISBN 978-1-259-59241-6
MHID 1-259-59241-3
Chief Product Officer, SVP Products & Markets: G. Scott Virkler
Vice President, General Manager, Products & Markets: Marty Lange
Vice President, Content Design & Delivery: Betsy Whalen
Managing Director: Thomas Timp
Brand Manager: Justin K. Wyatt, PhD
Director, Product Development: Rose Koos
Product Developer: Elizabeth Sievers
Marketing Manager: Patrick E. Reidy
Digital Product Developer: Michael Koot, PhD
Digital Product Analyst: Christine Carlson
Director, Content Design & Delivery: Linda Avenarius
Program Manager: Angela R. FitzPatrick
Content Project Managers: April R. Southwood/Jessica Portz/Christina Nelson, Sandra Schnee
Buyer: Jennifer Pickel
Design: Matt Backhaus
Content Licensing Specialists: Lori Hancock/Lorraine Buczek/DeAnna Dausener
Cover Image: ©Eric and David Hosking/Getty Images
Compositor: MPS Limited
Printer: LSC Communications
All credits appearing on page or at the end of the book are considered to be an extension of
the copyright page.
Library of Congress Cataloging-in-Publication Data
Names: Mason, Kenneth A., author.
Title: Understanding biology / Kenneth A. Mason, University of Iowa [and four
others].
Description: New York, NY : McGraw-Hill Education, [2018] | Includes index.
Identifiers: LCCN 2016048200 | ISBN 9781259592416 (alk. paper)
Subjects: LCSH: Biology.
Classification: LCC QH308.2 .M387 2018 | DDC 570--dc23 LC record available at
https://lccn.loc.gov/2016048200
The Internet addresses listed in the text were accurate at the time of publication. The inclusion of a website does not
indicate an endorsement by the authors or McGraw-Hill Education, and McGraw-Hill Education does not guarantee
the accuracy of the information presented at these sites.
mheducation.com/highered
mas92413_fm_i-xxiv.indd 2 28/11/16 12:26 pm
Brief Contents
About the Authors iv Part V The Diversity of Life 477
Changes to This Edition vi 22 Systematics and Phylogeny 477
A Learning Path to Understanding Biology viii 23 Prokaryotes and Viruses 497
24 Protists 522
Acknowledgments xvii
25 Fungi 548
Contents xviii 26 Plants 570
27 Animal Diversity 594
Part I The Molecular Basis of Life 1 28 Vertebrates 625
1 The Science of Biology 1
Part VI Plant Form and Function 656
2 The Nature of Molecules and the Properties of Water 21
29 Plant Form 656
3 The Chemical Building Blocks of Life 40
30 Flowering Plant Reproduction 681
Part II Biology of the Cell 66 31 The Living Plant 706
4 Cell Structure 66
Part VII Animal Form and Function 736
5 Membranes 94
6 Energy and Metabolism 115 32 The Animal Body and How It Moves 736
7 How Cells Harvest Energy 131 33 The Nervous System 761
34 Fueling the Body’s Metabolism 789
8 Photosynthesis 156
35 Maintaining Homeostasis 822
9 Cell Communication 179
36 Reproduction and Development 860
10 How Cells Divide 198
Part VIII Ecology and Behavior 893
Part III Genetic and Molecular Biology 222
37 Behavioral Biology 893
11 Sexual Reproduction and Meiosis 222
38 Ecology of Individuals and Populations 918
12 Patterns of Inheritance 238
39 Community Ecology 940
13 The Chromosomal Basis of Inheritance 259
40 The Living World 974
14 DNA: The Genetic Material 280
15 Genes and How They Work 304
16 Control of Gene Expression 332 Glossary G1
17 Biotechnology 358 Appendix A: Answer Key A-1
18 Genomics 383
Index I-1
Part IV Evolution 409
19 Genes Within Populations 409
20 The Evidence for Evolution 431
21 The Origin of Species 454
iii
mas92413_fm_i-xxiv.indd 3 28/11/16 12:26 pm
About the Authors
Kenneth Mason maintains an association with the University of Iowa, Department of Biology after having served
as a faculty member for eight years. His academic positions, as a teacher and researcher, include the faculty of the
University of Kansas, where he designed and established the genetics lab, and taught and published on the genetics
of pigmentation in amphibians. At Purdue University, he successfully developed and grew large introductory biology
courses and collaborated with other faculty in an innovative biology, chemistry, and physics course supported by the
National Science Foundation. At the University of Iowa, where his wife served as president of the university, he taught
introductory biology and human genetics. His honor society memberships include Phi Sigma, Alpha Lambda Delta, and,
© Kenneth Mason
by vote of Purdue pharmacy students, Phi Eta Sigma Freshman Honors Society.
Tod Duncan is a Clinical Assistant Professor at the University of Colorado Denver. He currently teaches first semester
general biology and coordinates first and second semester general biology laboratories. Previously, he taught general
microbiology, virology, the biology of cancer, medical microbiology, and cell biology. A bachelor's degree in cell biology with
an emphasis on plant molecular and cellular biology from the University of East Anglia in England led to doctoral studies
in cell cycle control, and postdoctoral research on the molecular and biochemical mechanisms of DNA alkylation damage
© Lesley Howard
in vitro and in Drosophila melanogaster. Currently, he is interested in factors affecting retention and success of incoming
first-year students in diverse demographics. He lives in Boulder, Colorado, with his two Great Danes, Eddie and Henry.
George Johnson is professor emeritus of biology at Washington University in Saint Louis, where he taught genetics
to biology majors and freshman biology to nonmajors for 35 years. Also professor of genetics at Washington University
School of Medicine, his research in population genetics focused on genetic variation in alpine butterflies. He has
published more than 40 scientific articles and authored six college texts, including Biology, The Living World, and
Essentials of the Living World, as well as the widely used high school biology textbook Holt Biology. In the 30 years he
has been authoring biology texts, over 3 million students have been taught from textbooks he has written.
© George Johnson
Jonathan Losos is the Monique and Philip Lehner Professor for the Study of Latin America in the Department of
Organismic and Evolutionary Biology and curator of herpetology at the Museum of Comparative Zoology at Harvard
University. Losos’s research has focused on studying patterns of adaptive radiation and evolutionary diversification
in lizards. He is the recipient of several awards, including the prestigious Theodosius Dobzhanksy and David Starr
Jordan Prizes, the Edward Osborne Wilson Naturalist Award, and the Daniel Giraud Elliot Medal from the National
© Jonathan Losos Academy of Sciences. Losos has published more than 100 scientific articles.
Susan Rundell Singer is the Laurence McKinley Gould Professor of Natural Sciences in the Department of
Biology at Carleton College in Northfield, Minnesota, where she has taught introductory biology, plant biology,
genetics, and plant development for 26 years. Her research focuses on the development and evolution of flowering
plants and genomics learning. Singer has authored numerous scientific publications on plant development and co-
authored education reports, including Vision and Change and “America’s Lab Report.” She received the American
Society of Plant Biology’s Excellence in Teaching Award and the Botanical Society’s Bessey Award, is an AAAS
fellow, served on the National Academies Board on Science Education, and chaired several National Research
© Susan Singer
Council study committees, including the committee that produced Discipline-Based Education Research.
Ian Quitadamo Lead Digital Author is a Professor with a dual appointment in Biological Sciences and Science
Education at Central Washington University in Ellensburg, Washington. He teaches introductory and majors biology
courses and cell biology, genetics, and biotechnology, as well as science teaching methods courses for future science
teachers and interdisciplinary content courses in alternative energy and sustainability. Dr. Quitadamo was educated
at Washington State University and holds a BA in biology, Masters degree in genetics and cell biology, and an
interdisciplinary Ph.D. in science, education, and technology. Previously a researcher of tumor angiogenesis, he now
investigates the behavioral and neurocognitive basis of critical thinking and has published numerous studies of factors
© Ian J. Quitadamo, Ph.D.
that improve student critical thinking performance. He has led multiple initiatives in critical thinking and assessment, and
is active nationally in helping transform university faculty practice.
iv
mas92413_fm_i-xxiv.indd 4 28/11/16 12:26 pm
Note to the Student
More than most subjects, biology is at its core a set of ideas and if you can master these basic ideas, you have a framework
to fit in the increasingly detailed information that will continue to accumulate. This book has been designed to help you do
just that. We have focused Understanding Biology, second edition, right where you need help—on the core ideas.
In keeping with that goal, the book provides a clear pathway through the forest of facts that can bog down
your understanding of biology. Each chapter begins with a Learning Path that introduces the major concepts
for the chapter. Then within each section these larger concepts are broken down into their supporting, more
specific concepts. Each of these comes with a learning objective that tells you what you should be able to do upon
completing the section, and each section has a brief review with a question to help you think about the concepts.
The key to this organization, and more important, to the content, is that you now have a book that presents the
important concepts of biology and supporting detail, but with a greater focus on understanding. The organization also
lends itself well to the digital tools that accompany the text. Understanding Biology, second edition, is part of a family of
learning tools, both print and digital, that are designed to help you understand biology and be successful in your studies.
Note to the Professor
Everyone teaching biology has been affected by the wave of change sweeping over college instruction these days.
Digital technologies have set off a revolution in how we teach, from online course management to interactive and
adaptive assessment; almost everything we do as instructors has changed. Yet the textbook itself has not changed
significantly. In fact, over the last 25 years we have seen the evolution of the encyclopedic text. These tomes of
biology were wonderful to catalog information but not necessarily to teach or learn biology in the ever-changing
classroom. This book represents an attempt to rethink how to present biology to the modern student.
Rather than remove context and supporting information, we have simply removed material that is not taught in
most classes. This allows us to focus on the concepts that are actually taught. In deciding what to include and what to
eliminate, we didn’t rely solely on our own experiences. Rather, we asked instructors across the country what chapters
in a majors biology text they taught, and what chapters they did not. Through a combination of an analysis of course
syllabi, custom orders, surveys, and reviews of preliminary versions of the text, you, the professors, have helped us
identify course topics. It may come as no surprise that most majors biology courses cover much of the material in the
first half of the book: the basic concepts of cell biology, genetics, and evolution. Professors who teach the second
half of the course pick and choose from chapters in the last half of the book. In this text we have also made strategic
decisions on content, retaining or expanding treatment in these basic areas to provide the context to facilitate student
learning. The rest of the text we have shortened. Whole chapters from a traditional text have not been eliminated, but
the treatments have become more focused on the key concepts, with unnecessary detailed reduced.
We also focused on helping students develop critical-thinking skills that will serve them well into the future.
Understanding Biology, second edition, provides two features that help develop critical thinking: end-of-chapter
Inquiry & Analysis and end-of-part Connecting the Concepts. While texts may present graphs and descriptions
of experiments, they rarely give students a taste of what it is like to “think” like a scientist. The Inquiry & Analysis
feature contains full-page scientific investigation based on real experiments carried out by laboratory scientists and
published in major journals. They walk the students through the scientific process, from formulating hypotheses and
experimentation through data analysis and forming conclusions. Connecting the Concepts is an end-of-part feature
that help students see how topics are related under unifying concepts. Seemingly unrelated topics are unified by
the same fundamental concepts that provide a framework to build knowledge upon knowledge.
We wrote this book because we have come to feel that while today’s biology textbooks reflect new content,
they do little to take advantage of new instructional opportunities. What sort of text would best serve a student
taking an online course? A course where classroom time is devoted to discussion rather than lecture? A course
delivered by computer, with interactive learning its mode of delivery? It is to address these diverse course offerings
that we have undertaken this new majors text. While Understanding Biology, second edition, will serve an instructor
very well in a traditional lecture course supporting the lectures with detailed explanations, its aim is broader: to
provide a tool that will support new teaching methods and online delivery methods as well.
about the authors v
mas92413_fm_i-xxiv.indd 5 28/11/16 12:26 pm
Changes to This Edition
The goal of the first edition of this book was to produce a text Chapter 8 Material was rewritten to clarify the nature of energy
containing the topics actually covered in the majority of introductory transactions during photosynthesis. Editing improves
biology classes at the depth that these topics are being taught. The clarity and readability of presentation.
second aim was to make the text as approachable to the student as Chapter 9 The material on the nature of receptors was rewritten
possible. In this revision, we have not changed the material covered, for clarity and accuracy. Material on RTKs and GPCRs
as our research for the first edition already indicated what is being was rewritten for clarity and accuracy.
taught. Instead, we have tried to improve the readability for the Chapter 10 The material on chromosome compaction was rewritten
student. One particular focus was cleaning up loose use of language for clarity and accuracy. The section on cancer was
in discussing chemical topics, especially those related to energy completely rewritten to introduce new material on
and chemical bonds. We have attempted to make the treatment of genomics of cancer and provide a more modern view.
chemical and physical concepts as accurate as possible, as well as
presented for maximum readability for the student. Part III Genetics and Molecular Biology
Chapter 11 The material on the synaptonemal complex
Part I The Molecular Basis of Life throughout the chapter was updated and rewritten
for clarity. This includes a new drawing of the
Chapter 1 The chapter was updated to clarify the relationship
synaptonemal complex, replacing an EM image that
between modern domains and traditional kingdoms.
was more difficult to see. The nature of monopolar
The section on important concepts to biology was
attachment to the spindle was clarified.
rewritten to reflect new use of these concepts in the
Chapter 12 The figure showing the relationship of genotype
Connecting the Concepts feature presented at the
to phenotype was moved from chapter 15 to this
end of every Part. Other edits were made for clarity
chapter, where it provides a much better context for
and readability for students.
students. The section on extensions to Mendel was
Chapter 2 Minor edits were made for clarity. Most edits were
rewritten for clarity.
related to the nature of chemical bonds, and to the
Chapter 13 The section on linkage was rewritten to improve
role of water in living systems.
clarity of this difficult concept. The material on genetic
Chapter 3 Edits were made to clarify the nature of energy in
mapping was also rewritten to improve readability
living systems, including the role of ATP. The text
for students. Information about SNPs in humans was
was edited to clarify the behavior of lipids in water.
updated, as was the material on source of changes in
The figure on the formation of peptide bonds was
chromosome number. The section on human genetic
modified to show amino acids in ionized form as they
diseases and prenatal screening was rewritten and
would be under physiological conditions. All changes
updated. The material on genomic imprinting was
increase accuracy and readability for students.
updated to reflect new information.
Chapter 14 The section on DNA structure was rewritten to clarify
Part II Biology of the Cell
the organic chemistry terminology used to describe
Chapter 4 The discussion of the structure and role of proteasome nucleotides. The description of the Watson–Crick
were updated, including evolutionary implications. structure of DNA was edited for clarity. The description
The section on cell junctions was edited to reduce of how telomerase functions was updated and rewritten
confusing language and increase consistency. to clarify action of the enzyme. The discussion of E. coli
Chapter 5 The material on transmembrane domains was polymerases was updated and rewritten for clarity.
completely rewritten to reduce confusing language Chapter 15 The Beadle and Tatum experiment and presentation
and improve readability. The material on the role of of the central dogma were rewritten for clarity and
membrane proteins was edited to improve accuracy readability. The material on eukaryotic transcription
and clarity. was updated to reflect new information from
Chapter 6 The chapter was rewritten to improve the genome-wide scans providing a new view of
presentation of concepts of energy. Material was polymerase pausing and promoter usage. The
edited to present the material in more chemically material on the integration of transcription and
appropriate language. Material on thermodynamics splicing was updated to provide a more modern view.
was rewritten to increase accuracy and readability The section on mutations was completely rewritten
for students. A new figure on entropy was included to reflect new data on human mutation rates.
to remove confusion introduced by the old figure. Chapter 16 The material on eukaryotic promoters and
Chapter 7 The chapter was rewritten to clarify concepts about transcription factors was updated to provide a
energy metabolism and make the discussions more modern view of the control of transcription.
more chemically accurate. Edits were also made to The section on the relationship between chromatin
improve clarity and readability. structure and the control of gene expression was
vi
mas92413_fm_i-xxiv.indd 6 28/11/16 12:26 pm
completely rewritten to incorporate new data and current thinking in terms of fungal phylogeny. The
present a more modern view of this critical topic. chapter was also edited for readability and clarity.
Chapter 17 The material on PCR was updated to include Chapter 26 Edits throughout emphasize the adaptations made by
reverse-transcription PCR (RT-PCR) and quantitative plants as they transitioned from an aquatic existence
RT-PCR. New sections were added to provide a more to a terrestrial one. The chapter was edited for clarity
contemporary perspective on molecular techniques and readability.
used in biotechnology. Modern techniques for Chapter 27 The chapter was edited throughout for clarity and
investigating gene function were added, including RNA readability.
interference, knockin mice, and the CRISPR genome
editing technology. Two new sections on modern Part VI Plant Form and Function
applications of biotechnology were added, which Chapter 29 Changes were made to section headings to emphasize
include the use of fluorescent in-situ hybridization and the key message of the section. The chapter was
gene chips in medical diagnostics.  edited for clarity and readability.
Chapter 18 The section on genome sequencing was updated Chapter 30 The chapter was edited throughout for clarity and
to reflect current high-throughput technologies. The readability.
material on the Human Genome Project was updated Chapter 31 The chapter was edited throughout for clarity and
to include information about the Cancer Genome readability.
Project, and new material on the wheat genome
project reveals the challenges of sequencing larger, Part VII Animal Form and Function
repetitive genomes. The section on bioinformatics
Chapter 32 The material on tissue types was rewritten to improve
was updated to include material on the use of mass
readability, and a new figure was added showing
spectrometry in proteomics.
the different types of epithelial tissue. The table
showing different types of neurons was changed to a
Part IV Evolution
new figure to improve clarity. The material on animal
Chapter 19 The section on variation in natural populations was locomotion was edited for accuracy and clarity.
completely rewritten to take into account new data. Chapter 33 The material on supporting cells was updated
This includes extensive material on variation in to include new information. The description of
human populations. Learning objectives throughout membrane potential and action potentials was
were rewritten for consistency and clarity. rewritten to improve clarity and readability.
Chapter 20 The chapter was edited throughout for clarity and Chapter 34 The chapter throughout was edited for clarity and
consistency. The material on biogeography was readability.
updated and rewritten for clarity. Chapter 35 The material on distinctions between receptor types
Chapter 21 The chapters was edited throughout for increased was rewritten for clarity. A discussion of the ability
readability for students. The material on biological of steroid hormones to act via membrane receptors
species concept and speciation was rewritten to was added to update the material in this section.
improve clarity. The section on the action and control of G proteins
in signaling was updated and rewritten. Material on
Part V The Diversity of Life osmoregulation in fresh- and saltwater fish was added.
Chapter 22 The material on cladistics was edited for clarity Chapter 36 The material on blocks to polyspermy was updated
and readability. The material on the evolution of for clarity and accuracy. The section on embryonic
multicellularity was edited for clarity. stem cells and the the reversal of determination was
Chapter 23 The prokaryotic genetics section was rewritten extensively updated to include new data and provide
for clarity and to provide a modern perspective to context for the student.
complement the historical material. The material on
Part VIII Ecology and Behavior
human diseases caused by infectious agents was
updated. A section on giant viruses was added to Chapter 37 The chapter was edited throughout for clarity and
provide information on this exciting new area. readability.
Chapter 24 The chapter was updated for accuracy, with new Chapter 38 The chapter was edited for clarity and accuracy. The
material added on control and treatment of malaria. data on human populations was updated.
Chapter 25 Updates focused on emphasizing the relationships Chapter 39 The material on mimicry was rewritten for clarity and
between structure and function in fungal forms. The accuracy. The material on keystone predator and
chapter was restructured, moving the more applied succession was updated for accuracy and readability.
aspects of mycology to the front of the chapter. Chapter 40 The chapter was edited throughout for clarity and
Changes to the Chytridiomycota section reflect readability.
changes to this edition vii
mas92413_fm_i-xxiv.indd 7 28/11/16 12:26 pm
A Learning Path to Understanding Biology
Understanding Biology and its online assets have been carefully thought out and crafted to help students and professors work efficiently
and effectively through the material in the course, making the most of study time and instructional goals.
The Learning Path
of seeds introduces into the life cycle a dormant phase, which allows
Each chapter is ▶ 26.6 Seed Plants Were a Key Step the embryo to survive until environmental conditions are favorable
26 in Plant Evolution for further growth.
organized in a way that A pollen grain is the male gametophyte
guides the studentC ONCEPPlaTnt s34.10 The Four Chambers of the Heart Talhloew hiinsgto trhyCe o af nOtchees NtloanrsCd opflE aanqPtusa itTsi cf i al3llegda4e w toi.t1 hc o1elvo onluizteioT hnaahrrsyhe i na nnCodv vaiatrirociendsu latSeoaecerhd y opfl awHnhtsi icpghro cdhouncwseis ttwas ooy fk ji unIsdsts a o fCfe gwao mceemltlos.p pPhoyltoleesns— gemraaidnles , a mndu lfteimceallluel—ar
Contract in a Cycle terrestrial teorrafi nAs. Eratrely irnineovsat,io nCs maadpe islulravivraile ons la,n ad pnosdsib leV. einmsale gametophytes, are conveyed to the egg in the female gameto-
through the key Later innovations drove a radiation of plant life that continues to phyte by wind or by a pollinator. In some seed plants, the sperm
concepts.3S4ys.1t0e.1m The CAutaotrorphdLsa nAdid aPaplLatenecdts t aAo rTrCee nMrreuiysltntircieagclll uL lilafPere a2 t6Dh.1rives the Cardiovascular cahnaimngael ltihfee. 3Hlan4idgs.c1ah1pe. 1 Pa nrd etAhse rasttmueorsrpeiheesres, aandn thdat sAupprotrets rdiivoerlsee s Hmntraaaotsevtvs et sote h tteoh wnEee aservedde odftohlerle sv esex gpeteglar dnnthat slr, to wtuohageth e w Wra th hogrilroeotu wmhgihans lgwe t hgpaiaocmlhnl eesnptdo eptru hmby etse.w , Tirmahti.hs Ie ner lctihmoanin--
BryoGpahmyetetos pHhayvtee aG Denoemraintaionnt 26.2 The Seed Protects the Embryo just theA s pfeermma,l em ogvaems etoto tphhey fteem faolrem gsa mweittohpinh ytthee. protection of the
Every chapter opens3A 4u▶.t1o0r.h2y thCmoSeneidcletss rVCLaaysccouepclSahrpy lPottelrlaosiSn spHttohesay mvE teesvn , oa Gal vDene ndodCe moL rReainoataiovofontensts , nH226t6..4re3aacrtito Mn iuss icnlieti aIste Idn bityi athtee dS Aby LoEf sAeReNdIsN. G33 O44BJ..E11C11T..I23VE 26.VC6.1ea ipLnisitsl tlh aeH reavioevlusteio F nLaorey rasmdsva nMatag uVess acslte iotNni vsitsuenuegleeu s.t m TaTwrehehne tco seoo, mvrciukporllle el eWtfaecnoltyidva reetnlh lycEel l sofsoxsurercmdr owihnuigntah dtiinhnne ga g dopdveriouttiloee.cn taIivln ed a iptnilsgosiiuodes sp paeorremr ocspa,h lytlehtdee
thmawtaci twihhnaa acplk otLsene rtca.h erTrnpohitunissgg ih hnPe ttalhhpteehsnA oVd en,o ad en.atural paSePcetedrG eoPyplamhmnyntwtsoei insWstp hT aPAee h“lArrareNFeemknnil arotaFgs k Rw EeiKeAoeerveedsnrloraepy siSlrt n ue PiSaevgtr,ltniemea eoPdds npnsl sta asA”n 2rt2esn66 2..5662d.76. 8impulses then travel to the ▲EidSsabarsavecebnneeemaal ddeeeaps  da oteesapt-inn urpnrorAi hcor bhvsdocayvnueaoedncirst drsue ce tmpse3tydeshcc astdoi ehar nst4f aoonsltfgo alhsoet e ,tes.edso hp1tugee .n delds edeaF1C eird en srfpvm.c voputslep4saoareiir lt nlnaerashuhdrs atln,atsa ethatidv,ilsopl nuo eibl oncagfn ioTf aitc doto retatueosherfrfh mtem t v igtiedanelhbeyresp mnadem r mapy ot b s oeihovsneLlr a baasloyedricm tryoodseaiosopndcs,rhum mn.er a yoaowr,inaS elbmsnp iaaseoainrpsk rneoustats edrenavt .h b rsnoeiM 3tt dr ovdhS0oeeaara ue5aand lt acly dni totthonereeogwxi n srro.e ict or 4d x flrteta s6aehttLs prnh 5meatpSeoedre tmr beimr smoaprmyrceeyltwrya emolasaoyslpc,ta s aeteacdnit crn.ronard tkteynondsn-- miinn RttghopRAsdSeephie Esoce yecopvVorstdeemaml IrrsbaEepssym; a.lWtaa iohlTjcn,mn enea hdtO snem tat dshcFnoapi evcclo r eCo eaatFa rdsgnOniyntu alvgoa cNmduilrolese oeeCtvs iwhtpme doEa lsetfpoutPo rsphhlmh rtTsy i acaa s tiTadene2.n l S ttle6ishoustex e .laeat 6tteahe drcpd he nstoms d fo pl releageuLrdloaneivt vte p.egeabaecr anuatr diistesnvrh ee,fe ee wign tsmeoh tm iahkcitlhebhnee r i liyis glfnoge lac,y asmcamiryiernd cnite loooeidng--. r
time, a two-layered wall develops around each microspore. As thyeo u unOdneer sstpaenrmd wunhiteesr ew ith the egg and forms a zygote, which oppflr aenectesd aeadp cptehaher at ops pheeaavreac necveto ilovofe dg nyfmro nmho sspepeorrmlep-sb ea anyrdin oagn pguliaons ptise drkmneso.w Snne eatds i fy itimso wthiteph fineo mtharele tp goaallmenne tgtor pachiny.ote bny wcined opr otthser. means. The sperm
mblaeritcgwreoer sespnao crased. -jAcaoct nethntaitsi n ppiaoniigrns t ,ao tnfh tehc ehbrai nmucbcolenertasitn ebu mreesai cktrsoo sdpmoowraetnus, r helae, vaevt hibneeg c wotmwaloel thteh dtsechpe oeevm rentmlwatoe ptonexs u prtic nioloaetloaufl r sfiao .nntts uhe cmeilnerbi r yuon istpeo, rTftcmctehhohhafaeeanett opce tfuCoeeotrrexileopalrot ntl a psicwnilt nlo reiiutn nnhdcs gtbettiahffi rm incaioeenogtnlrseon edt sgcmhyn eoyheta pfo crt Cieteewhsoalrat :ainficapntvchelte eee r Pte rpomasltg a.rsda ttT i ejvoohpdefri s rt soe l aa ntrt.i pATlohiesd o spthreeimr ssaprseyr mienn© Dra. dParvninodger Sde-thi the Learnpmaswplrhloeooidrwgcmehyi r sfmnpo nh arnga raotdyins cmlp uegineanlavrocrmesr espg.sae r T.osr emuhPP peisrn i,oor gfgir neyiparcpmrtlrohuong ddloyaitusnmtpcegtren hi roosimnens cp sdwoe enrasvmdshe aavlsorre gyepra dymvv seeasi nsmerctiv)spu.ee llrSea at,oro l a m tsnfieesedes a piudttur e ipossrlge aus(ynwn mtcwshln.eiicoathhr- ■2 6W.7hy isG wyatmer nnoot esspseentriaml fosr feArtrileiza tPiolna inn stese d plants?
pscoulllepntTu grheread i,on ausnt.edr ipt oclolnenta ginrsa icnh wemalilc alalys etrh aotf tmena yb reecaocmt wesi tbhe oatuhtiefrcusl oilnyn ceptrcseop niensai sttTeth dhoelefy ,pct hrbhiomeaucaspoarmtyne dienrsn.Cg do Ooft srNipcpeeCllrolmmasEis92d.413 P_ cnhE26_eEDSu5Tvti7rvou0enl-cnur5tsct9uii▲ot3ry en.di n doDEldf3x edLpt eie flo ae5romi7n0isun4 teshsse F Usuppnn.ictyt i1 oaebnend rremmgVi ntteisis srdsstuiueveebi dcrtiaahnnatge t rb amDepcaiiogdyml eyses oa tonaivnnde System08/1s1/16 9:4A0 amre rlomaevyepueirolree tsoi eFc(rfna rittolgwslmyu oa,rC n epoa rif2nom O6s dpp.eu1ovoc6Nrori)otn.la upgWnth Ciatyo i ahttnhdeaEa viptrnailys onPt sihcuadeeen Tm. docT veah egulel3cale eosed,plm 4ootthhgbreeeir.c . y ima3Tonl ehtiesgpe ga epmusrrpsomepotgTeeeracacnstnthpteig,vod cier eubre, mey pta ha rtDdoiennid vegsuix iedcttgeheerdaess estive Twraitcht “ NIsa kReedg Sueleadtse”d by
asah psoetuirgtldum rape rsto,o ct hseiregodnu atgolh w cwohhmeitcphhlee rat i dopenov.l elTelonhp etmu pbeoenl tlm eonaf y gt hlraeat iemnr ahelmaes e garagrmeea.est ocpahlyletde T“thCheoeen nt xucetntehrxeineatsc.nUip vtTtsntei enht fipogerlar orrtCttehh pcoeoeeef e nn tnmChtnilebnyoe TUr,sg ncyuent 1o tecbhdp. id ieneuena irpgTl nngasmh t utretgsaeo th Tr”nrsspatie rd r tsfacfoi esloCccoeoanestwnos satsseutln ua,ror ccifienth nerdg i aitp pgiphscletl oaacsositon tdins ort fsnsnhoe., nootlalhcdwoncoaduw s trhpi s tlo e eiipnrnwarm kowc v chhtwioido caPe hnsst ah ocrfee tt p hient sf o llowing taschealseeno d e b cgceogoD en atauttha.sr aiiIinlnnttUy g ca had o dfndimosd 1eepoivbdte.diei or n lsesoNneeup sdtpr mTo.wpe s Ppeliyhnertth orrtfae,h to vtearht cnh peattoehsi ns dreepig uvrnde ettierhenmsvvge em u,eal omrmoSelpresb einunoy rstglyits ogfis en nh mfgfiartf obroiiedmncryea o tonmndhd. treltoy o zu, iygtpahnghreoott ,ntdp eoturh.e dce Sse tees he netehdcHedees sotormmaocnhe stsimulateFerns and Alliess theGymnosperms releAngiospermsase of
believed to be the ancessttrraulc tsutraetse o fi nth ea nvgeritoesbpraetrem dsig. eAsti vree csyesntte m? (Select all that gastrin. What is the function of gastrin?
Pollination and the male gametophyte preasneanlytseids oinf dexifftaenrt,e nbat scahla paappnlygt.ei)orssp earrmes r erelvaetealded, ctohantn deicpltoeidd by a. GSatorsetdr foiond is a protease enzyme.
Pollination is simply the transfer of pollen from its source (an unifeynidnogsp ceormnsc ewpertes ainls ob icooalmo. gmEsyoo.n pT.h ahTgehuess efe imcoalne sg ianmdeitcoabp.th eyS tmwea hliln ai ntt eusntinifeying b. GI(nsateesegdtu rcmoieannt)t activates pepsinogen.
apnotlhlienra) ttioon a traekceesp ptilvaec ea rbeeat w(theeen s tfilgomwae rosf oaf fdliofwfeerreinntg p plalanntst) .a Mndo isst contuchneecslpee tassrp aewcrhieee stih llheuars sd tfriopaAultporeip,d dlny oocb.tr yeSt rittgiohphmletoa, iccndhou ecnnletdeio. nsApt eti rntmh tesh maero ecm htdeha.n eptL ,m atierotg rrei.es i ntestine cd.. GGaaEssmttbrrryiionn hstyimdruollaytzeess t hpero rteelienasTpas.lhehly e ltraoeecs fk,a ctrphyee ce fafopdluoosrwp ihengyrrsoto euagsnp, edsg nnforef ut aoiltipnsvh icdynht gaeH rsga, cyCatmneldrn.i sogtsiinpc keogrfom apnsh:gy ictoeossnp. ieTfrehmreosy-.
In them all, the ovule, which becomes a seed, rests exposed
brought about by insects, wind, water, gravity, bats, and other ani- primitive. 1. The primary function of the large intestine is to concentrate Apply on a scale (a modified shoot or leaf) and is not completely
enclosed by sporophyte tissues at the time of pollination.
mals. In as many as one-quarter of all angiosperms, however, a wastes into solid form (feces) for release from the body. How 1. Eating a meal that cont3a0i0n μms a loTth eo fn abmue ttgeyrm nwosiplelr tmr iglitgerearll yw mheiacnhs o“nfa ked seed.”
pollen grain may be deposited directly on the stigma of its own Germination and grodwotehs i to afc ctohmep slipsho trhoisp?hyte Figure 26.16 Crotshs see cftoiolnl oofw ani novgu?le. Amlatthuoruitgyh t hthee s oevedusle osf a grye mnankoespd eartm tsh ea rteim soem oef tpimolelsin eanticolons, eadt
flower, and self-pollination occurs. Pollination may or may not be a. By adding additional cells from the mucosal layer © Biology Media/Science Saou.r ceIncreased release of chyme biyn stpoo rotphhey ted tuisosudese.num
followed by fertilization, depending on the genetic compatibility As mentioned in section 2b6. .6B,y aa bsseoerdb inmga wy arteemr ain dormant for 582 Part V The Dibve.r sitCy oof nLifteraction of the gallbladder
of the pollen grain and the flower on whose stigma it has landed. many years, depending ocn. Bthye r eslepaesciinegs .s aWlthen environmental c. Inhibition of secretion
If the stigma is receptive, the pollen grain’s dense cytoplasm conditions become favorablde., tAhlel soefe tdh eu nabdoevrgeoes germination, and d. Increased secretion of pepsinogen and HCl
absorbs substances from the stigma and bulges through an aper- the young sporophyStey nptlhaenst izeemerges. Again depending on the mas92413_ch26_570-59S3.indyd n 58t2hesize 08/11/16 9:40 am
ture. The bulge develops into a pollen tube that responds to chemi- species, the sporophyt 1e. mCayhe gmriocwal daingde stdieovne ilnovpo lfvoers hmyadnroyl yyseisa rrse actions. Given what 1. Starving animals often exhibit swollen bodies rather than
cal and mechanical stimuli that guide it to the embryo sac. It before becoming capable oyfo rue pkrnoodwu catbioount, hoyrd irto mlyasiys qreuaicctkiolyn sg frroowm chapter 3, write the emaciated ones in early stages of their deprivation. Why?
hydrolysis reaction to break down the disaccharide lactose.
follows a diffusion gradient of the chemicals and grows down and produce flowers in a single growing season.
CONCEPT 34.4 Respiratory Systems Promote
tthakroeus gshe vtherea sl tyhloeu arsn dto i nttwo ot hdea mysi ctroo preyalec.h T thhee pmoilclerno ptyulbee, ubsuut atlhlye plants Wine c phraepsteenr t3 a0 .mCoOreN dCeEtaPileTd 3d4es.2cr iptFioono odf Irse pPrroodcucetsiosne din As It Passes Efficient Exchange of Gases
Through the Digestive Tract
journey may take up to a year. Pollen tube growth is more rapid in Understand
angiosperms than in gymnosperms. Understand 1. Fick’s Law of Diffusion states the rate of diffusion is directly
REVIEW OF CONCEPT 26.8
One of the pollen grain’s two cells, the generative cell, lags 1. The _______ and _______ play important roles in the proportional to
behind. Its nucleus divides in the pollen grain or in the pollen tube, Angiosperms are charactedrigizeesdti vbey porvoucleesss tbhya pt raot dpuoclilninga ctihoenm aircea ls that are required to a. the area differences between the cross section of the blood
producing two sperm cells. Unlike sperm in mosses, ferns, and enclosed within an ovaryd iagte stht ep robtaesines ,o lfi pai dcsa, rapnedl ,c aar bsotrhuycdturartee s. vessel and the tissue.
some gymnosperms, the sperm of flowering plants have no fla- unique to the phylum; a fruai.t dlievveer;l oppasn cfrroeams the ovary. Evob.lu ktiiodnn-eys; appendix b. the pressure differences between the two sides of the
c. liver; gallbladder d. pancreas; gallbladder membrane and how large an area is available for diffusion.
gella. At this point, the pollen grain with its tube and sperm has ary innovations of angiosperms include flowers to attract pol-
Apply c. the pressure differences between the inside of the organism
become a mature male gametophyte. linators, fruits to protect embryos and aid in their dispersal, and
1. The small intestine is specialized for absorption because it and the outside.
Double fertilization and seed production double fertilization, whicha .p riosv tihdee lsa estn sdeocstipoenr mof ttoh eh deilgpe nstoivueri strha ct and retains food the d. the temperature of the gas molecule.
the embryo.
longest. Apply
As the pollen tube enters the embryo sac, it destroys a synergid ■ What advantage doesb a. nh aasn sgaioclsipkee remxt egnasiino nbsy aplorondg uitcsi nlegn ag th that collect food. ▲ 1. Which of the following evolutionary adaptations to increase
in the process and then discharges its contents. Both sperm are fruit eaten by animals?c. has no outlet, so food remains within it for longer periods At the endga so efx tchhaen gceh aarep mteatrc, heeda ccohr rcecotlny?c e(Spelte cist aalls tshaet sasppeldy.) at three
functional, and an event called double fertilization follows. of time. different lae. vBeelasti.n Og cni liyao—uinr cfirerasste psuarfsasc et harreoaugh the chapter prior to
d. has an extremely large surface area that allows extended b. Bubbling gas into a fish tank—increases oxygen
▲ exposure to food. class, you wciolln cwenatnratt ioton dfoiffceuresn coesn questions at the “Understand”
At the end of each sSeynctthioesniz, eReview of Concept questions level. As yc.o uM egmabirna ngesr elianitnegr t hme alusntges rayre, yonoeu-c eclal lnay cerh tahilclek—nge yourself
1. How does the digestive system keep from being digested by decreases distance
allow you to check your tuhen gdaestrrisc tsaencrdetiinongs bit eprfoodruece ms?oving on with Appldy. aAn sdm aSlly dniatmheetseri zine bqacuteersiat—iodnescr etahsaest sruerqfaucei raere haigher
to the next concept. cognitive skills.
Chapter 34 Fueling the Body’s Metabolism 819
viii
mas92413_ch34_789-821.indd 819 11/11/16 11:29 am
mas92413_fm_i-xxiv.indd 8 28/11/16 12:26 pm
Chapter 26 Plants 589
mas92413_ch26_570-593.indd 589 08/11/16 9:41 am
Think Like a Scientist
Scientific Thinking figures throughout ◀ I nquiry & Analysis
the text walk you through a scientific WGlhuyc oDsoe Dini aTbheetiirc sU rEixncer?ete Effects of Eating on Blood Glucose Levels Inq features at the end
ePayonxrepudd e tCiorcio mtdinoeecnvnlusits,s, eTiloa efynusi.rnt StPgho reoomruc eete xtdahpluseero reHi mscy,h epRanoellttesshun.e lgtsseis, , Ldrtbcigmlanheailiacuustnseutokpoicldesra oroei- ttdononsushefege ndp e tr.i s tht noahetpeIio fktennl t a rmehd iaisn dewinm.poas isifhuabbIuad nbilelg l cio etiimnlhemnonut isse,dctci teom olishardsw ,s etb a eiahh h cro. roabi aosnelAnrosewe cmeeord seeist,f yoo phv, s’ agnuteehsbollers olul,rb ocow actoewgionhonnldlddailsu ysn etit c ’ ginhg snoiltl e osrucsttc a hsehrcpennee eoelle sama l sspietsscelh oidmoel sneluelrltegeailtsadrc ev ltr tymurrevotaa lloecc eebts ih tom sioaftrla mornikibantisr,egrmycn e a cg tt eouhhnuttelnoopeeesr- MBlood glucose level (m)11505 Kidney thresholdDNioarbmeatilc uiry & Analysis oyidnofev uetea vsiinelt,it rgpoya r aceti hsoseacnpni eittnenin rtmgi fit oacykr oeeu
▼ suenvtereraatl edti mcaesse st,h bel onoodr mglaulc ovsael uleev eolfs m4 amy Mbe;c oimn es eevneorre- 00 1 2 3 4 5 6 with experimental
mously elevated, up to 25 times the normal value. A char- Time (hours)
SimoTtPHnhferydae CecsputsdytRueco:Iti ercoe EtimOnmthdpigNooea loat cnstoovsuTyi:e oms mrtice:FIn ayssrFgT otth eua hIgcorsreCe uee ocrll lode(iso unc TniinadnystdurH tadieeecniuns erjIpce g daNaeoco r tswp eaeKmiIo tinndtaieshv jI rieiiime rNntopcei tvsmtrroseoeGits a egig)rmt deeubum gslyriaetnu aept loGotraruoorot2rsong ceo ereyo fo,ots f emt oftch e ccteeeroyeoilno tllu nel sd cndesiyisd.v itvt ioeIris.es rpiTgiaoolhaotnnmes .,mmy ei nenc fjiatero.on csImft i biso .en goccpmkwooelfeoiheo lnnncMlxedt aey nrecrsPtot lyaehTTe clFclsr aohh (oe l.nCaemeemf s,t s dChtt paeomhhkal idfeeenCn)itc xt,se c2 dose tneia hskdpm sl ia cl iruse mwptoa-cs nlpilteyiepsleztrfec ,lyihou ldysnaem mli c nwptfieyohgnrrpasctaoel riselhm tnoai -eetnirgmchgeine.yn we hgf ocT ateifkotlhncirhierire net nkieso sgse atukr fn si,fkoted gehiayartnei a sh ernudntp ynee initoot dz nisdftsoyrg eeiimrifmet svro ild sveayeliete estedca uc t ayn wmhrertscdeoaaltaullgi,tt is nc itundi aodstepi fAdcbohghcsnrolwfoc-ifoaiunaea l fvfdrs dtassesmmtetl ct ieoiie seeacocearaeesvrri toro ertipr rito iondhil eigo ssrTnlrndaevfegfeaenyeete nuv oamu hier n o1t ce.,rrmalmanecc y0 fdtoyioml fld mhoo iTenss0gus regionti yrmama?e onrhhonanrhwgrol.smalegygb”teeeut --trutpes a pa enpg hrwbtmIetteoh esnsordi f sos ts mt ioh ohrsigonmftobp ne.lf oous ulgne ragf t(lc lWm ylulbgmoeuifslctlavoshcu ouuoseleooyeno css nd s ,oei-ia elt,ncd smrmi o iandeedoenrel ei ieiae llvse)atdemcsd shxinnhd daoceosad’ nulgt r ltvii u“dee alnaeu3ecrt ilbddetsixc0au ein, doc v-li tdeedm.neseib .odses is Tywai Tu s ntb iihfoaashsvureceltlo eeot eeto te i mdhrrkncns .aier aie tan Bnadr (ncm etarcnnlrdhexosedkeee edtc oity 1c, a iro da u-oelbffh voirngtl entoevnuit eltoherueouilis)nyydcesrf-t. 2. bI bn.. tlgtCtdtIieohhensliros nuaeedpttmb gchi dlrvdeoe epeidivtosartdaioeeesbciurnele e liapa?sgbetnn eilv eic’gDrytsfe s o p ctlaobp areuttnleokoraor’ sies tvonorh ebefdtneso tl ?a .ougrt te IoHrl tssunwdh ot ct e htwghdoo ielnos cul toseoihchemr no le?mtegs phlve aaeede lcvl o lentpes evola es eernrb lxmisysetco fattednooalei’r k sfderf ee b e tttfrlhuhooeerenron t dt htf ooe r rydapeocarsatutuiac vtl.tiot itAsci e iesans snty eocdorca upcinarrh ethdaeteal dlttleh paone nyg oliinnuge
cytoplasm cytoplasm plex regulation. intervals. The dotted line indicates the kidney threshold, kidney threshold?
The Cell Cycle Can Be Halted ft(ahlubeio dmu pta a1xs0is mimnugMm th) rctohouangtc heth niett r wakthiidoennne ayol fli sob fal oibtolse dg tloug clruoecstoreis-eetvr aemn fsorpoleomcrut itlnheges b. Ibthsl orteohsdehr ogel ldau?nc yo speo lienvte alst wdoh incoht tehxec deieadb tehtiec kiniddniveyid ual’s analysis skills.
at Three Checkpoints channels are being utilized full-bore. 3. Making Inferences
a. Why do you suppose the diabetic individual
tPreroagteeds toeorocnyete- Arrested oocyte Oocyte in meiosis I LkeEyA cRhNeIcNkGp oOinBtJsE inC TthIVe Ee u10ka.6r.y2o ticD cisetliln cgyucilseh. the rolesA onf tahley thsriese tdoooske? so much longer to recover from the test
CpRPoreoessndiutciillvctue:t si oIirnoenjnge: :uc IftlT aemhtdoei troo poosrcfios ym gitseea ssdtu trperivarrooetignnore nbe :tys rM sep aaforttosumimrteiav ntGeito 2 rcn e ai gnPutursoolea mmsto oeprtisriono, sgdtihs uFe cIan.tci octonyt roo (fpM alaP sFm). Aamhralablttrhietkordeau.dr gy Thb h yfpeo h raac cseclelahls re,iu ctsytkhe pwes o etic hnheetals lv eae it t tdshweirvlhefiie dc erhced hc ttoehhcgeekn epcizuyoekcisnlae trs ty hcobarteoniect h bc peeth ol1lda .c seaeylsA aassc.y,el p eesRoope dsfnilea n y caictotitohdohnsrnei gn s nuCgo moarmn icncuagelr p tvihtnese.d Witveishdta udta oilss’s et hboelfo igomldu mcgoleusdcei?oa stHee oilmewvp e alsc t 4. bDse. rcaWeErxewxotcpeirunl esalgtdwie n C yeg.oeoltuun u cceorlxiusnpesee?i?oc Etn xtshp elWa ninhoy.r m Tdhaoel d idniaidabibevetiidtciuc ia nilnd tdiovi vi diduuaalsl?
from a mitotic cell should cause a G1 cell to enter mitosis. internal state and to integrate external signals (figure 10.16). The
Tfreosmt: thMe pGh1 apshea cseel lcse allr ies fmusoendit owriethd Gm1i cprhoassceo pcieclalsll,y t.hen the nucleus cahs elcaktep oiinn tms aertea plhoacsaete d(t haet tshpei nGd1l/eS cahnedc Gkp2/oMin tb).o uPnadssaargiees ,t hasro wugelhl Insulin not present Insulin present
tfholelsoew sth.ree checkpoints is controlled by the Cdk enzymes, as Glucose Insulin
The G1/S checkpoint
The G1/S checkpoint is the primary point at which the cell
M phase cell G1 phase cell Fused cells “decides” whether or not to divide. This checkpoint is therefore
FCreuogrnutchlaleutros Eiro xtnhp:ae tCr icmyatoeupnseltasss: amH c oferwollm tco aM ne npbthoeatrh sm eoi tfco tehslilesss. ceo enxtapienrsim ae pnotss ibtivee ttcahhyneecd lp cenry,u icmatlrseia t.wr ioIyetn lp.ilos a itnsh tte ah tep w hpahhsiaecsh ed e utxrhtiaentrg nl aiwnl khsisigc chne aglllsr odcwiavntih sii noffanlcu tteoonr ccs eeal elf vfgeercnott wst hothef Irnescuelpintor trGacnhlusacpnoonsreteler Glucose
rationalized? What would be the next step in characterizing these
factors? Chapter 34 Fueling the Body’s Metabolism 817
nFdeiivcgeiussisroaenr y.1 0fo.1r 4c elDl-icsyccolev eprryog oref spsoiosni.t iTvehe rseeg sutuladtioesr ionfd cicealtl ed that HConcentrationigh mCMasyP9c2Fl4i na13c_ticvhi3ty4_789-821.indd 817 11/11/16 11:29 am
iDnN yAea ssty tnhtehrees iws e(rcea ltlwedo cSrTiAticRaTl )c oanntdr otlh peo cinotms:m thitem ceonmt mtoi tmmietnots itso. Low Uncovering Connections Between Concepts
pOanses inpga rbtioctuhl aorf tgheensee, bnoaumnedda rciedsc.2, was shown to be critical for G2 M G1 S G2 M G1 S G2 M
MPF is cyclin plus cdc2 Figure 10.15 Correlation of MPF activity, amount of
Afollll oowf itnhge steh friened ionbgsse crvaamtieo ntosg. eFthiresrt ,i nt haen perleogteainnt feanschoiodned w bityh tthhee ccoyncclienn ptrraotitoeni na,n adn MdP sFt aagcteivsi toy fa trhe ep lcoettlel dc yvcsl. es.t agCey ocfl itnh e cell ◀ A “Connecting the Concepts” feature at
cdc2 gene was shown to be a protein kinase. Second, the purifica- cycle. Both change in a similar repeating pattern through the cell
tion and identification of MPF showed that it was composed of cycle. The reason for this correlation is that cyclin is actually one the end of each Part in the text shows
both a cyclin component and a kinase componenCt (ofignurne 1e0.c15t)i. ng ctohmpeo nCenot onf McPeF, tphet osth ePr baerintg aI Ic y cBlin-idoepleongdeynt koinafs et he Cell
Third, kinase was shown to be the Cdc2 protein! (Cdk). Together, these act as a positive regulator of cell division. how seemingly isolated concepts in
Life descended from early cells over 3.5 BYA. Over life’s hiCsthoarpy,t ecre l1l0s h aHvoew a dCaepltlesd D ainvdid dei ve2rs1ifi1ed into hundreds of different types. The diversity of
life is driven by how organisms acquire and process energy in the highly regulated reactions of photosynthesis and respiration. Plants have
specialized organs, tissues, and cells to convert the Sun’s energy to chemical energy. Eukaryotes have specialized organelles that carry out the different chapters are connected by
regulated reactions of aerobic respiration.
Mason_ch10.indd 211 08/09/16 5:14 pm unifying concepts of biology.
(cid:127) Early life did not use oxygen. (cid:127) Life descended from early cells that spontaneously
(cid:127) Some prokaryotes adapted to anaerobic arose over 3.5 billion years ago.
environments by using molecules other than oxygen (cid:127) All cells have a plasma membrane, cytoplasm, and DNA
as the final electron acceptor in cellular respiration. centrally located either in a nucleoid or a nucleus, but
(cid:127) Fermentation is an anaerobic process that uses vary in other structures.
organic compounds as electron acceptors. (cid:127) Prokaryotic cells lack compartmentalization.
(cid:127) Aemleearcdotebr oiocnx ryaegcsecpenirp aattvoiaor inala nubdslee e.sv ooxlvyegde na fatesr t pheh ofitnoasly nthesis odSroognam’tn eisusme sO 2 ofa orcneee olcl rsoog mra mpnAoioslsrmleeds (cid:127) cPelanntrtsa lc veallcsu hoalevse(cid:127), cAwelhtlhli lwoeu a gallhns, i mcchharlloo cmreoolplsslao lsamtcsek, sathtnreudsc letau rfrgeeae dt uiffreesr.s
(cid:127)(cid:127)(cid:127) LPpLmcwmheehiaigolanaoovmlfiveterm oesoceltseisupnrzy nulletaean gcsrmssttet ht uwhoes erts.laxhese pto eiceasaf u.rl mnl l loiledgoawsihsinn sstign , ,fo wao tprhnrgil tdaegahn an csdtsseps i leeff flaosxceb rctwr rshe uoiantmhrntb i gnp ose ifcgp oatmehnnceedtia fin ictn stnalPdetpada erarofsisehtnysotohp thEedev ixouvopfnel luliraitstfyiieino tasynnd process of cell division.the controlledarise fromAll cells (cid:127)(cid:127) PLbDcbcrehoaeirNnqorrmtAaogwukprme aiesyrlrrete eo yrfiadxnusosn, o cts tpddehmtiuro suemoern e heke .o a aa tvEaronvroeuny del gkdouc e aa ottdfein rumosiysvonino npimadc tgolntieeecilfdoex cmds n gelciio ziviueatreniocrkns.aesuai ooli llrsmsayny i rtm oeboi stsyi e l asr,.
Sun’s energy plants absorb. segregate chromosomes accurately.
(cid:127) Pbilnandtss o uxsyeg erunb, irsecvoe tros ifinxg CcaOr2b bount fi rxuabtiisocno. also
(cid:127) mC4i nainmdiz CeA pMh optloarnetssp hiraavteio and.aptations to
(cid:127) Photosynthetic organisms
(cid:127)(cid:127) capLmwoaPlricceeimegaaoitnfnxohgham ahppcnpdoeowhikccitttvoor rttte-teuuughogee-iisr nodrrrs atsyAdprp eeaednetyan h T io ne esspinlitletPtlciwht.tlph eg e re litesmaieininehhfccsmt nentdrteSrt oo Cerdu.sdete ulo fhn e OcencnoanNnetechnt2err’usA usr metersri.rg Delng yemee ya noPyssnt icht t fH ceahtfo tearhi rneo o glad snmyti s s Photo-synthesisuses lightenergy to makecTorganic molechules haegennorgevmeregosrynd yanellLanmiveitcirrsngagyn ss&fy osm rtmCeaemltlctso eosromgrtmxiapo endotiidzcuarienbvdoelsism Liti vrdanbaipryefnenr oCpf goersrrcee iemastegndicycsuabdsatslateial to iocsteoekn nmnd ss Proteirn erkgeiucneliaasrps tetceesaodrpr seopfnhucdol ylstycoplTehhloerat yic-oelnl
inhibition
(cid:127)(cid:127)(cid:127) TAPwetelihvhvnhlhlaiee eoniotcn rt gbffoght o uilsyw oilefay-lelootnonlrl’wreyatgslhdr n ilagcteo.shcayssfeto liti fls vwrla omaiatsowwin ierhndslssdeg fco ia r nreofites v.ltm laohuacl enlvtathr ieroome prnc oeShesdsu ancpynn rnsi igrtayaaiesncmtstiadoe ili c nmnitsso .a ei nrtnhe ee r gy (cid:127)(cid:127)(cid:127) aauAEOEennnlsnTxeedoeePicddtr r tthsgag rhtyoetyyoeinn ro rfi.tcr renhc orel-eaeermnersaarei dtsisfeeroue.g rocdpsytd r, id o o lfiiutrnnkoor e itnm(nhr Negge odA r cfnaoDoeedxr+l li)m,mue rslne aoohtarlsufe c rtAtctethiTluoseaPlpn ete. is rdlt aeocrtica vitopernot u nirsse NeCddtcroxeeoaoantpnnwamcesci ealentpshpcpd lafettt osiotsso r,n ypn o“fio rsifLolnu ”lCi vf ’viuovnioidnesr ntmeig hnnsd aeeges.ty e csitsotnhuitnn eeptgw mp ootshr tein g
a learning path to understanding biology ix
mas92413_fm_i-xxiv.indd 9 28/11/16 12:26 pm