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Today & Tomorrow
5e
Cecie Starr | Christine A. Evers | Lisa Starr
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Biology Today and Tomorrow, Fifth Edition Cecie Starr, Christine A. Evers, Lisa Starr
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1 Invitation to Biology
Unit 1 How Cells work
2 Molecules of Life
3 Cell Structure
4 Energy and Metabolism
5 Capturing and Releasing Energy
Unit 2 GenetiCs
6 DNA Structure and Function
7 Gene Expression and Control
8 How Cells Reproduce
9 Patterns of Inheritance
10 Biotechnology
Unit 3 evolUtion and diversity
11 Evidence of Evolution
12 Processes of Evolution
13 Early Life Forms and the Viruses
14 Plants and Fungi
15 Animal Evolution
Unit 4 eColoGy
16 Population Ecology
17 Communities and Ecosystems
18 The Biosphere and Human Effects
Unit 5 How animals work
19 Animal Tissues and Organs
20 How Animals Move
21 Circulation and Respiration
22 Immunity
23 Digestion and Excretion
24 Neural Control and the Senses
25 Endocrine Control
26 Reproduction and Development
Unit 6 How Plants work
27 Plant Form and Function
28 Plant Reproduction and Development
B r
IE F
C o
N T
E N
T S
BC
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1 Invitation to Biology 1.1 the secret life of earth 4
1.2 life is more than the sum of its Parts 4
1.3 How living things are alike 6
Organisms Require Energy and Nutrients 6
Organisms Sense and Respond to Change 6
Organisms Grow and Reproduce 6
1.4 How living things differ 8
What Is a Species? 8
A Rose by Any Other Name 10
1.5 the science of nature 11
Thinking About Thinking 12
How Science Works 12
Examples of Experiments in Biology 13
1.6 the nature of science 16
Bias in Interpreting Experimental Results 16
Sampling Error 17
Scientific Theories 18
The Scope of Science 19
UNIT 1 HOw CELLS wORk
2 Molecules of Life 2.1 Fear of Frying 24
2.2 start with atoms 25
Why Electrons Matter 26
2.3 From atoms to molecules 28
Ionic Bonds 28
Covalent Bonds 28
2.4 Hydrogen Bonds and water 29
Water Is an Excellent Solvent 30
Water Has Cohesion 31
Water Stabilizes Temperature 31
2.5 acids and Bases 32
2.6 organic molecules 33
What Cells Do to Organic Compounds 33
2.7 Carbohydrates 34
2.8 lipids 36
Fats 36
Phospholipids 36
Waxes 37
Steroids 37
2.9 Proteins 38
The Importance of Protein Structure 39
2.10 nucleic acids 41
3 Cell Structure 3.1 Food for thought 46
3.2 what, exactly, is a Cell? 46
The Cell Theory 46
Components of All Cells 47
Constraints on Cell Size 47
How Do We See Cells? 48
3.3 Cell membrane structure 50
Membrane Proteins 51
3.4 introducing Prokaryotic Cells 52
Biofilms 53
3.5 introducing eukaryotic Cells 54
The Nucleus 54
The Endomembrane System 54
Mitochondria 55
Chloroplasts 56
The Cytoskeleton 56
Extracellular Matrix 58
Cell Junctions 58
3.6 the nature of life 59
C C
o N
T E
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S
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4 Energy and Metabolism 4.1 a toast to alcohol dehydrogenase 64
4.2 life runs on energy 65
4.3 energy in the molecules of life 66
Why Earth Does Not Go Up in Flames 67
Energy In, Energy Out 68
4.4 How enzymes work 68
The Need for Speed 68
Factors That Influence Enzyme Activity 69
Cofactors 70
Metabolic Pathways 71
Controlling Metabolism 71
Electron Transfers 72
4.5 diffusion and membranes 73
Semipermeable Membranes 73
4.6 membrane transport mechanisms 75
Passive Transport 75
Active Transport 76
Membrane Trafficking 76
5 Capturing and Releasing Energy
5.1 a Burning Concern 82
5.2 to Catch a rainbow 83
Storing Energy in Sugars 84
5.3 light-dependent reactions 85
5.4 light-independent reactions 87
Alternative Carbon-Fixing Pathways 87
5.5 a Global Connection 89
Aerobic Respiration in Mitochondria 89
5.6 Fermentation 92
5.7 Food as a source of energy 94
Complex Carbohydrates 94
Fats 94
Proteins 95
UNIT 2 GENETICS
6 DNA Structure and Function 6.1 Cloning 100
6.2 Fame, Glory, and dna structure 102
Discovery of DNA’s Function 102
Discovery of DNA’s Structure 104
DNA Sequence 105
6.3 dna in Chromosomes 106
6.4 dna replication and repair 108
How Mutations Arise 108
7 Gene Expression and Control 7.1 ricin, riP 114
7.2 Gene expression 115
7.3 transcription: dna to rna 116
RNA Modifications 117
7.4 the Genetic Code 118
7.5 translation: rna to Protein 119
7.6 Products of mutated Genes 122
7.7 Control of Gene expression 124
Master Genes 124
Sex Chromosome Genes 125
Lactose Tolerance 125
DNA Methylation 126
CONTENTS v
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8 How Cells Reproduce 8.1 Henrietta’s immortal Cells 132
8.2 multiplication by division 133
Cytoplasmic Division 136
8.3 mitosis and Cancer 137
Cell Division Gone Wrong 137
Cancer 138
Telomeres 139
8.4 sex and alleles 140
On the Advantages of Sex 140
8.5 meiosis in sexual reproduction 142
How Meiosis Mixes Alleles 144
From Gametes to Offspring 144
9 Patterns of Inheritance 9.1 menacing mucus 150
9.2 tracking traits 151
Mendel’s Experiments 151
Inheritance in Modern Terms 151
9.3 mendelian inheritance Patterns 152
Monohybrid Crosses 153
Dihybrid Crosses 154
9.4 Beyond simple dominance 155
Incomplete Dominance 155
Codominance 155
Pleiotropy and Epistasis 156
9.5 Complex variation in traits 158
Continuous Variation 159
9.6 Human Genetic analysis 160
Types of Genetic Variation 160
9.7 Human Genetic disorders 161
The Autosomal Dominant Pattern 162
The Autosomal Recessive Pattern 163
The X-Linked Recessive Pattern 164
9.8 Chromosome number Changes 165
Autosomal Change and Down Syndrome 166
Change in the Sex Chromosome Number 166
9.9 Genetic screening 168
10 Biotechnology 10.1 Personal Genetic testing 174
10.2 Finding needles in Haystacks 175
Cutting and Pasting DNA 175
DNA Libraries 176
PCR 177
10.3 studying dna 178
Sequencing the Human Genome 178
Genomics 179
DNA Profiling 179
10.4 Genetic engineering 181
Genetically Modified Microorganisms 181
Designer Plants 181
Biotech Barnyards 182
10.5 modifying Humans 184
Gene Therapy 184
Eugenics 185
UNIT 3 EVOLUTION AND DIVERSITy
11 Evidence of Evolution 11.1 reflections of a distant Past 190
11.2 Confusing discoveries 191
11.3 a Flurry of new ideas 192
Squeezing New Evidence Into Old Beliefs 192
Darwin and the HMS Beagle 193
A Key Insight—Variation in Traits 194
Great Minds Think Alike 195
11.4 Fossil evidence 196
The Fossil Record 196
vi CONTENTS
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CONTENTS vii
Radiometric Dating 197
Missing Links 199
11.5 drifting Continents 200
Putting Time Into Perspective 201
11.6 evidence in Form 204
Morphological Divergence 204
Morphological Convergence 205
11.7 evidence in Function 206
Patterns in Animal Development 207
12 Processes of Evolution 12.1 superbug Farms 212
12.2 alleles in Populations 213
An Evolutionary View of Mutations 213
Allele Frequency 214
12.3 modes of natural selection 215
Directional Selection 215
Stabilizing Selection 217
Disruptive Selection 217
12.4 natural selection and diversity 218
Survival of the Sexiest 218
Maintaining Multiple Alleles 219
12.5 Genetic drift and Gene Flow 220
Bottlenecks and the Founder Effect 220
Gene Flow 221
12.6 speciation 222
Reproductive Isolation 222
Allopatric Speciation 224
Sympatric Speciation 224
12.7 macroevolution 226
Evolutionary Theory 228
12.8 Phylogeny 229
Applications of Phylogeny 230
13 Early Life Forms and the Viruses 13.1 the Human micobiome 236
13.2 on the road to life 237
Conditions on the Early Earth 237
Origin of the Building Blocks of Life 237
Origin of Metabolism 238
Origin of Genetic Material 238
Origin of Cell Membranes 239
13.3 origin of the three domains 240
Reign of the Prokaryotes 240
Origin of Eukaryotes 241
13.4 viruses 242
Viral Structure and Replication 242
Bacteriophages 242
Plant Viruses 243
Viruses and Human Health 243
HIV—The AIDS Virus 244
Ebola 245
New Flus 245
13.5 Bacteria and archaea 246
Structure and Function 246
Reproduction and Gene Transfers 246
Metabolic Diversity 247
Domain Archaea 248
Domain Bacteria 248
13.6 Protists 250
Flagellated Protozoans 250
Foraminifera 251
Ciliates 251
Dinoflagellates 252
Apicomplexans 252
Water Molds, Diatoms, and Brown Algae 254
Red Algae 255
Green Algae 255
Amoebas and Slime Molds 256
Choanoflagellates 257
14 Plants and Fungi 14.1 Fungal threats to Crops 262
14.2 Plant traits and evolution 263
Life Cycle 263
Structural Adaptations to Life on Land 264
Reproduction and Dispersal 264
14.3 nonvascular Plants 265
Mosses 265
Liverworts and Hornworts 266
14.4 seedless vascular Plants 266
Ferns 266
Horsetails and Club Mosses 267
14.5 rise of the seed Plants 269
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14.6 Gymnosperms 270
Conifers 270
Cycads and Ginkgos 271
Gnetophytes 271
14.7 angiosperms—Flowering Plants 272
Floral Structure and Function 272
A Flowering Plant Life Cycle 273
Keys to Angiosperm Diversity 273
Major Groups 273
Ecology and Human Uses of Angiosperms 274
14.8 Fungal traits and diversity 274
Yeasts, Molds, Mildews, and Mushrooms 274
Lineages and Life Cycles 275
14.9 ecological roles of Fungi 277
Decomposers 277
Parasites 277
Fungal Partnerships 278
Human Uses of Fungi 279
15 Animal Evolution 15.1 medicines From the sea 284
15.2 origins and diversification 285
Animal Origins 285
Evidence of Early Animals 285
Major Groups and Evolutionary Trends 286
15.3 invertebrate diversity 288
Sponges 288
Cnidarians 288
Flatworms 289
Annelids 290
Mollusks 290
Roundworms 291
Arthropods 292
Echinoderms 296
15.4 introducing the Chordates 297
Chordate Traits 297
Invertebrate Chordates 297
Vertebrate Traits and Trends 298
15.5 Fishes and amphibians 299
Jawless Fishes 299
Jawed Fishes 299
Early Tetrapods 300
Modern Amphibians 301
15.6 escape From water—amniotes 302
Amniote Innovations 302
Nonbird Reptiles 302
Birds 303
Mammals 303
15.7 Human evolution 305
Primate Traits 305
Primate Origins and Diversification 305
Australopiths 306
Early Humans 307
Homo Sapiens 308
Neanderthals and Denisovans 308
UNIT 4 ECOLOGy
16 Population Ecology 16.1 a Honkin’ mess 314
16.2 Characteristics of Populations 315
Demographic Traits 315
Collecting Demographic Data 316
16.3 Population Growth 317
Exponential Growth 317
Carrying Capacity and Logistic Growth 318
Density-Independent Factors 319
16.4 life History Patterns 320
Biotic Potential 320
Describing Life Histories 320
Evolution of Life Histories 321
Predation and Life History Evolution 322
viii CONTENTS
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CONTENTS ix
16.5 Human Populations 323
Population Size and Growth Rate 323
Fertility Rates and Future Growth 324
Effects of Industrial Development 325
17 Communities and Ecosystems 17.1 Fighting Foreign Fire ants 330
17.2 Community structure 331
Nonbiological Factors 331
Biological Factors 331
17.3 direct species interactions 332
Commensalism and Mutualism 332
Interspecific Competition 333
Predator–Prey Interactions 334
Plants and Herbivores 335
Parasites and Parasitoids 335
17.4 How Communities Change 337
Ecological Succession 337
Adapted to Disturbance 338
Species Losses or Additions 338
17.5 the nature of ecosystems 339
Overview of the Participants 339
Food Chains and Webs 339
Primary Production and Inefficient Energy Transfers 341
17.6 Biogeochemical Cycles 342
The Water Cycle 342
The Phosphorus Cycle 342
The Nitrogen Cycle 344
The Carbon Cycle 345
The Greenhouse Effect and Global Climate Change 346
18 The Biosphere and Human Effects 18.1 Going with the Flow 352
18.2 Factors that affect Climate 353
Air Circulation Patterns 353
Ocean Circulation 354
18.3 the major Biomes 355
Forest Biomes 355
Grasslands and Chaparral 356
Deserts 356
Tundra 356
18.4 aquatic ecosystems 358
Freshwater Ecosystems 358
Marine Ecosystems 358
18.5 Human impact on the Biosphere 360
Increased Species Extinctions 360
Deforestation and Desertification 362
Acid Rain 362
Biological Accumulation and Magnification 363
The Trouble With Trash 363
Destruction of the Ozone Layer 364
Global Climate Change 364
18.6 maintaining Biodiversity 366
The Value of Biodiversity 366
Conservation Biology 366
Ecological Restoration 367
Reducing Human Impacts 368
UNIT 5 HOw ANIMALS wORk
19 Animal Tissues and Organs 19.1 Growing replacement Parts 374
19.2 animal structure and Function 375
Organization and Integration 375
Evolution of Structure and Function 376
19.3 types of animal tissues 376
Epithelial Tissues 376
Connective Tissues 378
Muscle Tissues 379
Nervous Tissue 380
19.4 organs and organ systems 380
Organ Systems 382
19.5 regulating Body temperature 384
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20 How Animals Move 20.1 Bulking Up muscles 390
20.2 skeletal systems 391
Types of Skeletons 391
The Human Skeleton 392
Bone Structure and Function 392
Where Bones Meet—Skeletal Joints 393
20.3 Functions of skeletal muscles 395
20.4 How muscle Contracts 396
Muscle Components 396
Sliding Filaments 397
20.5 Fueling muscle Contraction 398
20.6 exercise and inactivity 398
21 Circulation and Respiration 21.1 a shocking save 404
21.2 How substances are moved through a Body 405
Open and Closed Circulatory Systems 405
Evolution of Vertebrate Cardiovascular Systems 406
21.3 Human Cardiovascular system 407
21.4 the Human Heart 408
The Cardiac Cycle 409
Setting the Pace of Contractions 409
21.5 Blood and Blood vessels 410
Components and Functions of Blood 410
High-Pressure Flow in Arteries 410
Adjusting Resistance at Arterioles 411
Capillary Exchange and Function of the Lymph Vessels 411
Back to the Heart 412
21.6 Blood and Cardiovascular disorders 412
Blood Disorders 412
Cardiovascular Disorders 413
21.7 animal respiration 414
Two Sites of Gas Exchange 414
Respiratory Systems 414
21.8 Human respiratory Function 416
From Airways to Alveoli 416
How You Breathe 417
Exchanges at Alveoli 418
Transport of Gases 418
Respiratory Disorders 418
22 Immunity 22.1 Frankie’s last wish 424
22.2 responding to threats 425
The Defenders 426
22.3 innate immunity mechanisms 427
Normal Flora 427
Surface Barriers 427
Complement 428
Phagocytosis 428
Inflammation and Fever 429
Examples of Innate Responses 430
22.4 antigen receptors 431
Antigen Processing 432
22.5 adaptive immune responses 434
Example of an Antibody-Mediated Response 434
Example of a Cell-Mediated Response 436
22.6 immunity Gone wrong 438
Overly Vigorous Responses 438
Immune Deficiency and AIDS 439
22.7 vaccines 441
23 Digestion and Excretion 23.1 Causes and effects of obesity 446
23.2 two types of digestive systems 446
23.3 digestive structure and Function 448
In the Mouth 448
Swallowing 448
The Stomach 449
Digestion in the Small Intestine 450
Absorption in the Small Intestine 451
Concentrating and Eliminating Wastes 452
23.4 Human nutrition 453
Carbohydrates 453
Fats 454
Proteins 454
Vitamins and Minerals 454
USDA Dietary Recommendations 455
23.5 Fluid regulation 456
Fluid Homeostasis 456
Fluid Regulation in Invertebrates 456
Vertebrate Urinary System 457
x CONTENTS
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CONTENTS xi
23.6 kidney Function 458
How Urine Forms 458
Feedback Control of Urine Formation 459
Impaired Kidney Function 460
24 Neural Control and the Senses 24.1 impacts of Concussions 466
24.2 animal nervous systems 467
Invertebrate Nervous Systems 467
Vertebrate Nervous Systems 467
24.3 neuron Function 468
Three Types of Neurons 468
Neuroglia—Neuron Helpers 469
Resting Potential 469
The Action Potential 470
The Chemical Synapse 471
Disrupted Synaptic Function 472
Psychoactive Drugs 472
24.4 the Central nervous system 474
Regions of the Human Brain 474
A Closer Look at the Cerebral Cortex 476
The Limbic System—Emotion and Memory 476
The Spinal Cord 477
24.5 the Peripheral nervous system 478
24.6 the senses 480
Sensory Reception and Diversity 480
Sensation to Perception 480
The Chemical Senses—Smell and Taste 481
Detecting Light 482
The Human Eye 482
At the Retina 484
Hearing 484
Sense of Balance 486
The Somatosensory Cortex 487
25 Endocrine Control 25.1 endocrine disrupters 492
25.2 Hormone Function 493
Types of Hormones 494
Hormone Receptors 494
25.3 the Hypothalamus and Pituitary 496
Posterior Pituitary Function 496
Anterior Pituitary Function 496
Growth Disorders 496
25.4 thyroid and Parathyroid Glands 498
Thyroid Hormone 498
Regulation of Calcium 499
25.5 the Pancreas 500
Controlling Blood Glucose 500
Diabetes Mellitus 501
25.6 the adrenal Glands 502
25.7 Hormones and reproductive Function 504
Gonads 504
The Pineal Gland 504
26 Reproduction and Development 26.1 assisted reproduction 510
26.2 modes of reproduction 511
Asexual Reproduction 511
Sexual Reproduction 511
Variations on Sexual Reproduction 511
26.3 stages of animal development 512
26.4 Human reproductive Function 514
Female Reproductive Anatomy 514
Egg Production and Release 515
The Menstrual Cycle 516
Male Reproductive Anatomy 517
How Sperm Form 518
Sexual Intercourse 518
A Sperm’s Journey 519
26.5 reproductive Health 520
Contraception 520
Infertility 521
Sexually Transmitted Diseases 522
26.6 Human development 523
Fertilization 523
From Cleavage to Implantation 524
Embryonic and Fetal Development 525
Functions of the Placenta 528
Maternal Effects on Prenatal Development 528
26.7 Birth and milk Production 529
Childbirth 529
Nourishing the Newborn 529
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UNIT 6 HOw PLANTS wORk
27 Plant Form and Function 27.1 leafy Cleanup Crews 534
27.2 tissues in a Plant Body 535
Eudicots and Monocots 537
27.3 stems, leaves, and roots 538
Stems 538
Leaves 540
Roots 542
27.4 Fluid movement in Plants 544
Water Moves Through Xylem 544
Sugars Flow Through Phloem 545
27.5 Plant Growth 546
28 Plant Reproduction and Development
28.1 Plight of the Honeybee 554
28.2 sexual reproduction 555
A New Generation Begins 558
28.3 seeds and Fruits 560
28.4 early development 562
28.5 asexual reproduction 564
Agricultural Applications 564
28.6 Plant Hormones 565
Auxin 566
Cytokinin 567
Gibberellin 568
Abscisic Acid 568
Ethylene 568
28.7 Growth responses 570
Tropisms 570
Photoperiodic Responses 572
appendix i answers to self-Quizzes
appendix ii Periodic table of the elements
appendix iii a Plain english map of the Human Chromosomes
appendix iv Units of measure
xii CONTENTS
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P
P r
E Fa
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Biology is a huge field, with a wealth of new discover- ies being made every day, and biology-related issues such as climate change, stem cell research, and per- sonal genetics often making headlines. This avalanche of information can be intimidating to non-scientists. This book was designed and written specifically for students who most likely will not become biologists and may never again take another science course. It is an accessible and engaging introduction to biology that provides future decision-makers with an under- standing of basic biology and the process of science.
a wealth of applications This book is packed with everyday applications of biological processes. At every opportunity, we enliven discussions of biologi- cal processes with references to their effects on human health and the environment. This edition also con- tinues to focus on real world applications pertaining to the field of biology, including social issues arising from new research and developments. Descriptions of current research, along with photos of scientists who carry it out, underscore the concept that biology is an ongoing endeavor carried out by a diverse commu- nity of people. Discussions include not only what was discovered, but also how the discoveries were made, how our understanding has changed over time, and what remains to be discovered. These discussions are provided in the context of an accessible introduction to well-established concepts that underpin modern biology. Every topic is examined from an evolutionary perspective, emphasizing the connections between all forms of life.
accessible text Understanding stems from mak- ing connections between concepts and details, so a text with too little detail reads as a series of facts that beg to be memorized. However, excessive detail can overwhelm the introductory student. Thus, we con- stantly strive to strike the perfect balance between level of detail and accessibility. We once again revised the text to eliminate details that do not contribute to a basic understanding of essential concepts. We also know that English is a second language for many introductory students, so we avoid idioms and aim for a clear, straightforward style.
Analogies to familiar objects and phenomena will help students understand abstract concepts. For exam- ple, in the discussion of transpiration in Chapter 27 (Plant Form and Function), we explain that a column of water is drawn upward through xylem as a drinker draws fluid up through a straw.
in-text learning tools To emphasize connections between biological topics, each chapter begins with an application section that explores a current event or controversy directly related to the chapter’s content. For example, a discussion of binge drinking on col- lege campuses introduces the concept of metabolism in Chapter 4. This section presents an overview of the metabolic pathway that breaks down alcohol, linking the function of enzymes in the pathway to hangovers, alcoholism, and cirrhosis. The section is illustrated with a photo of a tailgate party that preceded a recent Notre Dame–Alabama football game, and also a photo of Gary Reinbach just before he died at age 22 of alcoholic liver disease. (In the index, you’ll find health-related applications denoted by red squares and environmental applications by green squares.)
To strengthen a student’s analytical skills and offer insight into contemporary research, each chapter includes an exercise called digging into data that is placed in a section with relevant content. The exer- cise consists of a short text passage—usually about a published scientific experiment—and a table, chart, or other graphic that presents experimental data. A student can use information in the text and graphic to answer a series of questions. For example, the exercise in Chapter 2 asks students to interpret results of a study that examined the effect of dietary fat intake on “good” and “bad” cholesterol levels.