100.1 Contents

UNIT 1 What is Life Made of? Chemistry, Cells, Energy

CHAPTER 1

Process of Science 1

Java Report

Making sense of the latest buzz in health-related news

   1.1 Conflicting Conclusions 3

   1.2 Science Is a Process: Narrowing Down the Possibilities 4

   1.3 Anatomy of an Experiment 6

   1.4 Sample Size Matters 7

   1.5 Everyday Theory vs. Scientific Theory 8

   1.6 Side Effects of Caffeine 10

   1.7 Correlation Does Not Equal Causation 12

   1.8 From the Lab to the Media: Lost in Translation 14

CHAPTER 2

Chemistry and Molecules of Life 20

Mission to Mars

Prospecting for life on the red planet

   2.1 Five Functional Traits of Life 25

   2.2 Touchdown, Gale Crater 26

   2.3 All Matter Is Made of Elements 27

   2.4 Carbon Is a Versatile Component of Life’s Molecules 29

UP CLOSE Molecules of Life: Carbohydrates, Proteins, Lipids, Nucleic Acids 30

   2.5 A Layer Rich in Phospholipids Defines Cell Boundaries 33

   2.6 Water Is Polar and Forms Hydrogen Bonds 34

   2.7 Hydrogen Bonds Give Water Its Unique Properties 35

   2.8 Water Is a Good Solvent 36

   2.9 Solutions Have a Characteristic pH 37

   2.10 On the Fringe 38

CHAPTER 3

Cell Structure and Function 44

Wonder Drug

How a chance discovery in a London laboratory revolutionized medicine

   3.1 How Penicillin Was Discovered 46

   3.2 Cell Theory: All Living Things Are Made of Cells 47

   3.3 Prokaryotic and Eukaryotic Cells Have Different Structures 48

   3.4 Water Flows across Cell Membranes by Osmosis 49

   3.5 Some Antibiotics Inhibit Prokaryotic Ribosomes 52

   3.6 Membranes: All Cells Have Them 53

   3.7 Molecules Move across the Cell Membrane 55

   3.8 Eukaryotic Cells Have Organelles 56

UP CLOSE Eukaryotic Organelles 58

M1 MILESTONES IN BIOLOGY

Scientific Rebel 66

Lynn Margulis and the theory of endosymbiosis

   M1.1 Chloroplasts and Mitochondria Share Traits with Bacteria 69

   M1.2 The First Eukaryotes Were Products of Endosymbiosis 70

xviii

CHAPTER 4

Nutrition, Metabolism, enzymes 74

The Peanut Butter Project

A doctor’s crusade to end malnutrition in Africa, a spoonful at a time

   4.1 Hunger around the World 77

   4.2 Food Is a Source of Macronutrients 78

   4.3 Macronutrients Build and Maintain Cells 79

   4.4 Enzymes Facilitate Chemical Reactions 82

   4.5 Enzymes Catalyze Reactions by Lowering Activation Energy 83

TABLE 4.1 A Sample of Micronutrients in Your Diet 85

   4.6 Vitamins and Minerals Have Essential Functions 86

   4.7 Peanut Butter-Based RUTF Saves More Children 88

   4.8 A Balanced Diet 90

CHAPTER 5

Energy and Photosynthesis 94

The Future of Fuel

Scientists hope to make algae into the next global energy source

   5.1 Distribution of Recoverable Oil Reserves 96

   5.2 U.S. Energy Consumption 98

   5.3 Algae Capture Energy in Their Molecules 99

   5.4 Energy Is Conserved 100

   5.5 Energy Conversion Is Not Efficient 101

   5.6 Autotrophs Convert Light Energy into Chemical Energy 102

   5.7 Photosynthesis Captures Sunlight to Make Food 103

   5.8 The Energy in Sunlight Travels in Waves 106

   5.9 Photosynthesis: A Closer Look 107

TABLE 5.1 How Green Are Biofuels? 108

Americans burn through 378 million gallons of gasoline a day, enough to fill about 540 Olympic-size swimming pools.

— CHAPTER 5

CHAPTER 6

Dietary Energy and Cellular Respiration 114

Supersize Me?

The biology and culture of our expanding waistlines

   6.1 Obesity Is Influenced by Biology and Culture 116

   6.2 Body Mass Index (BMI) 117

   6.3 Americans Eat Large Portions 118

   6.4 Food Powers Cellular Work 120

TABLE 6.1 Calories In, Calories Out 121

   6.5 Glycogen and Fat Store Excess Calories 122

   6.6 ATP: The Energy Currency of Cells 124

   6.7 Aerobic Respiration Transfers Food Energy to ATP 125

   6.8 Aerobic Respiration: A Closer Look 126

   6.9 Fermentation Occurs When Oxygen Is Scarce 127

   6.10 Photosynthesis and Aerobic Respiration Form a Cycle 129

xix

UNIT 2 How Does Life Perpetuate? Cell Division and Inheritance

CHAPTER 7

DNA Structure and Replication 136

Biologically Unique

How DNA helped free an innocent man

   7.1 What Is DNA, and Where Is It Found? 139

   7.2 DNA Is Made of Two Strands of Nucleotides 140

   7.3 DNA Structure Provides a Mechanism for DNA Replication 142

   7.4 The Polymerase Chain Reaction Amplifies Small Amounts of DNA 144

   7.5 DNA Profiling Uses Short Tandem Repeats 146

   7.6 Creating a DNA Profile 147

   7.7 DNA Profiling Uses Many Different STRs 148

M2 MILESTONES IN BIOLOGY

The Model Makers 154

Watson, Crick, and the structure of DNA

   M2.1 The DNA Puzzle 156

   M2.2 Rosalind Franklin and the Shape of DNA 157

   M2.3 Erwin Chargaff’s Work Provided a Clue to Base Pairing 158

   M2.4 The Structure Is Finally Known: The DNA Double Helix 159

CHAPTER 8

Genes to Proteins 162

Medicine from Milk

Scientists genetically modify animals to make medicine

   8.1 Amino Acid Sequence Determines Protein Shape and Function 165

   8.2 Chromosomes Include Gene Sequences That Code for Proteins 166

   8.3 Antithrombin Deficiency Can Cause Blood Clots 167

   8.4 Genes to Proteins: Different Alleles Influence Protein Function 168

   8.5 The Two Parts of a Gene 169

   8.6 Making a Transgenic Goat 171

   8.7 Gene Expression: An Overview 173

   8.8 Transcription: A Closer Look 174

   8.9 Translation: A Closer Look 175

   8.10 The Genetic Code Is Universal 176

M3 MILESTONES IN BIOLOGY

Sequence Sprint 182

Venter and Collins race to decode the human genome

   M3.1 DNA Sequencing: Hierarchical Shotgun Method 184

   M3.2 DNA Sequencing: Whole-Genome Shotgun Method 186

   M3.3 New Technology Cut DNA Sequencing Time and Cost 187

   M3.4 Linking Genes to Disease 190

CHAPTER 9

Cell Division and Mitosis 192

Nature’s Pharmacy

From the bark of an ancient evergreen tree, a cancer treatment blockbuster

   9.1 Why Do Cells Divide? 195

   9.2 The Cell Cycle: How Cells Reproduce 196

TABLE 9.1 Drugs from Plants 198

UP CLOSE Cell Cycle and Mitosis 200

   9.3 Taxol Interferes with Mitosis 202

   9.4 Cell Division Is Tightly Regulated 203

   9.5 Cancer: When Checkpoints Fail 204

   9.6 Taxol Prolongs Survival in Cancer Patients 207

xx

CHAPTER 10

Mutations and Cancer 212

Fighting Fate

When cancer runs in the family, ordinary measures are not enough

   10.1 Mutations in the BRCA1 Gene Increase the Risk of Cancer 215

   10.2 Replication Errors and Other DNA Damage Can Produce New Alleles 216

   10.3 Mutations Can Be Hereditary or Nonhereditary 217

TABLE 10.1 Incidence of Hereditary Diseases in Different Populations 218

   10.4 Mutations in DNA Can Alter Protein Function and Cause Cancer 219

   10.5 What Causes Mutations? 220

   10.6 Mutations in Two Types of Cell Cycle Genes Cause Most Types of Cancer 221

   10.7 Tumors Develop in Stages as Mutations Accumulate in a Cell 222

   10.8 BRCA Mutations Increase the Risk of Breast and Ovarian Cancer 223

TABLE 10.2 Reducing the Risk of Cancer 224

CHAPTER 11

Single-Gene Inheritance and Meiosis 228

Rock for a Cause

From patient to performer, shining the spotlight on a genetic disease

   11.1 CF Is Caused by Mutations in the CFTR Gene 230

   11.2 Humans Have Two Copies of Nearly Every Gene 232

   11.3 Gametes Pass Genetic Information to the Next Generation 233

   11.4 Meiosis Produces Haploid Egg and Sperm 234

   11.5 Meiosis Produces Genetically Diverse Egg and Sperm 235

   11.6 The CFTR Protein and Cystic Fibrosis 236

   11.7 How Recessive Traits Are Inherited 238

   11.8 How Dominant Traits Are Inherited 239

TABLE 11.1 Inherited Genetic Conditions in Humans 240

   11.9 Tracking the Inheritance of Two Genes 241

Mendel provided a new explanation for heredity, decades before the word “genetics” was coined.

— MILESTONE 4

M4 MILESTONES IN BIOLOGY

Mendel’s Garden 248

An Austrian monk lays the foundation for modern genetics

   M4.1 Theories of Inheritance before Mendel 250

   M4.2 Mendel’s Experiments 252

   M4.3 Mendel’s Law of Segregation 253

   M4.4 Mendel’s Law of Independent Assortment 254

CHAPTER 12

Complex Inheritance 256

Q&A: Genetics

Complexities of human genetics, from sex to depression

   12.1 X and Y Chromosomes Determine Human Sex 258

TABLE 12.1 Between Male and Female: Varieties of Sex and Intersex 260

   12.2 X-Linked Traits Are Inherited on X Chromosomes 261

   12.3 Female Carriers Can Pass Disease Alleles to Their Children 262

xxi

   12.4 Y Chromosomes Pass Largely Unchanged from Fathers to Sons 264

   12.5 DNA Links Sally Hemings’s Son to Jefferson 265

   12.6 Hair Texture Exhibits Incomplete Dominance 268

   12.7 Human Blood Type Is a Codominant Trait 269

   12.8 A Mismatched Blood Transfusion Causes Immune Rejection 270

   12.9 Human Height Is Both Polygenic and Multifactorial 272

   12.10 Serotonin Transporter Function Is Linked to Depression 273

   12.11 Depression Is a Multifactorial Trait 274

   12.12 Chromosomal Abnormalities: Aneuploidy 276

   12.13 Amniocentesis Provides a Fetal Karyotype 277

CHAPTER 13

Stem Cells and Cell Differentiation 282

Grow Your Own

Stem cells could be the key to engineering organs

   13.1 Stem Cells in Tissues Have Regenerative Properties 285

   13.2 Cells Are Organized into Tissues, Organs, and Systems 286

   13.3 Engineering an Organ Using Stem Cells 286

TABLE 13.1 How Old Are You? 288

   13.4 Specialized Cells Express Different Genes 289

   13.5 Regenerative Medicine: Four Approaches 290

   13.6 Embryonic vs. Adult Stem Cells 292

   13.7 Somatic Cell Nuclear Transfer Produces Cloned Embryonic Stem Cells 294

   13.8 Induced Stem Cells 295

   UNIT 3 How Does Life Change over Time? Evolution and Diversity

CHAPTER 14

Natural Selection and Adaptation 302

Bugs That Resist Drugs

Drug-resistant bacteria are on the rise. Can we stop them?

   14.1 The Bacterium Staphylococcus aureus 305

   14.2 How Beta-Lactam Antibiotics Work 307

   14.3 How Bacteria Reproduce 308

   14.4 How Bacterial Populations Acquire Genetic Variation 309

   14.5 An Organism’s Fitness Depends on Its Environment 310

   14.6 Evolution by Natural Selection 311

   14.7 Patterns of Natural Selection 312

   14.8 Preventing and Treating Infection by Antibiotic-Resistant Bacteria 315

M5 MILESTONES IN BIOLOGY

Adventures in Evolution 320

Charles Darwin and Alfred Russel Wallace on the trail of natural selection

   M5.1 Lamarckianism: An Early Idea about Evolution 323

   M5.2 Darwin’s Voyage on the Beagle 324

   M5.3 The Evolution of Darwin’s Thought 326

   M5.4 The Evolution of Wallace’s Thought 328

Scientists are now seeing bacterial infections that don’t respond to any known antibiotics, leading many to fear the day when we run out of treatment options altogether.

— CHAPTER 14

xxii

CHAPTER 15

Nonadaptive Evolution and Speciation 330

Urban Evolution

How cities are altering the fate of species

   15.1 Population Genetics 333

   15.2 Gene Pools of New York City Mouse Populations 335

   15.3 Genetic Drift Reduces Genetic Diversity 336

   15.4 Gene Flow Increases Genetic Diversity in Populations 338

   15.5 City Mouse and Country Mouse 340

TABLE 15.1 Adaptive and Nonadaptive Mechanisms of Evolution 341

UP CLOSE Calculating the Hardy-Weinberg Equilibrium 342

   15.6 Species Are Reproductively Isolated 346

   15.7 Speciation: How One Species Can Become Many 347

CHAPTER 16

Evidence for Evolution 352

A Fish with Fingers?

A transitional fossil fills a gap in our knowledge of evolution

   16.1 Fossils Form Only in Certain Circumstances 356

   16.2 Fossils Reveal Changes in Species over Time 357

   16.3 How Fossils Are Dated 359

   16.4 Tiktaalik, an Intermediate Fossilized Organism 363

   16.5 Forelimb Homology in Fish and Tetrapods 364

   16.6 Vertebrate Animals Share a Similar Pattern of Early Development 365

   16.7 Related Organisms Share DNA Sequences 367

CHAPTER 17

Life on Earth 372

Q&A: Evolution

From moon rocks to DNA, clues to the history of life on Earth

   17.1 Unstable Elements Undergo Radioactive Decay 375

   17.2 Radioactive Decay Is Used to Date Some Rock Types 376

   17.3 Geologic Timeline of Life on Earth 378

   17.4 Movement of Earth’s Plates Influences Climate and Biogeography 380

   17.5 How Many Species Are There? 382

   17.6 Classification of Species 383

   17.7 How to Read a Phylogenetic Tree 384

   17.8 Genetics Defines Three Domains of Life: Bacteria, Archaea, Eukarya 386

CHAPTER 18

Prokaryotic Diversity 390

Lost City

Probing life’s origins at the bottom of the sea

   18.1 Hydrothermal Vents of Lost City Provide an Extreme Environment for Life 392

   18.2 Investigating Life in Lost City 394

   18.3 Prokaryotic Cells Are Small and Lack Organelles 396

   18.4 Prokaryotes Are Abundant and Diverse 397

   18.5 Bacteria and Archaea, Life’s Prokaryotic Domains 398

   18.6 Exploring Bacterial Diversity 400

   18.7 Exploring Archaeal Diversity 402

   18.8 Energy from the Earth Fuels Life at Lost City 404

xxiii

“[Lost City] is a good example of what we really don’t know and what there is to still discover on the seafloor.”

— GRETCHEN FRÜH-GREEN, CHAPTER 18

CHAPTER 19

Eukaryotic Diversity 410

Rain Forest Riches

Restoring eukaryotic diversity in Olympic National Park

   19.1 Tree of Life: Domain Eukarya 412

   19.2 The Landscape of Olympic National Park 413

   19.3 Evolution of Plant Diversity 414

   19.4 Evolution of Animal Diversity 417

   19.5 Fungi, the Decomposers 422

   19.6 The Challenge of Classifying Protists 423

CHAPTER 20

Human Evolution 430

Skin Deep

Science redefines the meaning of racial categories

   20.1 Humans Are Genetically Similar 432

   20.2 Melanin Influences Skin Color 433

   20.3 Folate and Vitamin D Are Necessary for Reproductive Health 435

   20.4 Human Skin Color Correlates with UV Light Intensity 436

   20.5 Mitochondrial DNA Is Inherited from Mothers 437

   20.6 Modern Human Populations Share a Common Female Ancestor 438

   20.7 Out of Africa: Human Migration 439

   20.8 Traits of Modern Humans Reflect Evolutionary History 440

   20.9 Natural Selection Influences Human Evolution 442

   20.10 The Evolution of Skin Color 444

UNIT 4 What Makes Up Our Environment? Ecology

CHAPTER 21

Population Ecology 448

On the Tracks of Wolves and Moose

Ecologists learn big lessons from a small island

   21.1 Ecology of Isle Royale 451

   21.2 Distribution Patterns Influence Population Sampling Methods 452

   21.3 Population Distribution Patterns 453

   21.4 Population Growth and Carrying Capacity 455

   21.5 Population Cycles of Predator and Prey 456

   21.6 Patterns of Population Growth 457

   21.7 Moose and Wolf Health Is Monitored by a Variety of Data 458

   21.8 Abiotic and Biotic Influences on Population Growth 459

   21.9 A Warming Climate Influences Moose and Wolf Population Size 462

xxiv

CHAPTER 22

Community Ecology 466

What’s Happening to Honey Bees?

A mysterious ailment threatens a vital link in the food chain

   22.1 Bees Are Keystone Species 468

   22.2 Commercial Crops Require Bees 469

   22.3 Flowering Plant Reproduction Relies on Pollinators 470

   22.4 Energy Flows up a Food Chain 472

   22.5 A Honey Bee Food Web 473

   22.6 Organisms May Live Together in Symbioses 474

   22.7 Pollinators Have Different Ecological Niches 476

   22.8 Bees Compete for Resources 477

   22.9 What Is Causing Colony Collapse Disorder? 480

CHAPTER 23

Ecosystem Ecology 486

The Heat Is On

From migrating maples to shrinking sea ice, signs of a warming planet

   23.1 U.S. Maple Syrup: A Thing of the Past? 488

   23.2 Rising Temperatures Affect Plant Behavior 489

   23.3 Maple Tree Range Is Affected by Rising Temperatures 491

UP CLOSE Biomes 492

   23.4 The Greenhouse Effect 493

   23.5 Earth’s Surface Temperature Is Rising with Increases in Greenhouse Gases like Carbon Dioxide 494

   23.6 Rising Temperatures Mean Widespread Ecosystem Change 495

   23.7 Arctic Temperatures Are Rising Fast 497

   23.8 Arctic Sea Ice Is Melting 498

   23.9 The Carbon Cycle 499

UP CLOSE Chemical Cycles 500

   23.10 Measuring Atmospheric Carbon Dioxide Levels 502

   23.11 Anthropogenic Production of Greenhouse Gases 503

M6 MILESTONES IN BIOLOGY

Progress or Poison? 510

Rachel Carson, pesticides, and the birth of the environmental movement

   M6.1 Widespread Use of DDT to Kill Mosquitoes and Lice 513

   M6.2 Unintended Consequences of Using DDT 514

   M6.3 Biomagnification 515

“In its simplest sense, sustainability is just doing things today to ensure a vibrant successful future for others.”

— STACEY SWEARINGEN WHITE, CHAPTER 24

CHAPTER 24

Sustainability 520

The Makings of a Green City

One Kansas town reinvents itself sustainable

   24.1 The Human Ecological Footprint 524

xxv

   24.2 The Human Ecological Footprint Is Greater than Earth’s Biocapacity 526

   24.3 Countries Differ in Their Ecological Footprint 527

   24.4 Fossil Fuels Are Nonrenewable 528

   24.5 Human Population Growth 532

   24.6 Species Loss Increases as Human Population Grows 534

   24.7 Nonfossil Fuel Resources Reduce Our Ecological Footprint 536

   24.8 Water Is a Renewable Resource 537

   24.9 Depletion of Freshwater by a Growing Population 539

   24.10 Water Availability Is Not Equally Distributed 540

   24.11 What You Can Do to Live More Sustainably 541

Answers 546

Glossary 555

Photo Credits 564

Index 569