Brief Contents
Part I The Origin of Living Things  1
     1 The Science of Biology  1
     2 The Nature of Molecules  19
     3 The Chemical Building Blocks of Life  35
     4 The Origin and Early History of Life  61
Part II Biology of the Cell  79
     5 Cell Structure  79
     6 Membranes  105
     7 Cell-Cell Interactions  125
     8 Energy and Metabolism  143
     9 How Cells Harvest Energy  159
     10 Photosynthesis  185
     11 How Cells Divide  207
Part III Genetic and Molecular Biology  227
     12 Sexual Reproduction and Meiosis  227
     13 Patterns of Inheritance  241
     14 DNA: The Genetic Material  279
     15 Genes and How They Work  301
     16 Gene Technology  319
     17 Genomes  343
     18 Control of Gene Expression  361
     19 Cellular Mechanisms of Development  381
     20 Cancer Biology and Cell Technology  405
Part IV Evolution  433
     21 Genes Within Populations  433
     22 The Evidence for Evolution  453
     23 The Origin of Species  471
     24 Evolution of Genomes and Developmental Mechanisms  491
Part V Diversity of Life on Earth  509
     25 Systematics and the Phylogenetic Revolution  509
     26 Viruses  531
     27 Prokaryotes  545
     28 Protists  561
     29 Overview of Plant Diversity  579
     30 Fungi  599
     31 Overview of Animal Diversity  617
     32 Noncoelomate Invertebrates  633
     33 Coelomate Invertebrates  651
     34 Vertebrates  683
Part VI Plant Form and Function  729
     35 Plant Form  729
     36 Vegetative Plant Development  755
     37 Transport in Plants  767
     38 Plant Nutrition  781
     39 Plant Defense Responses  795
     40 Sensory Systems in Plants  807
     41 Plant Reproduction  831
Part VII Animal Form and Function  855
     42 The Animal Body and How It Moves  855
     43 Fueling Body Activities: Digestion  887
     44 Circulation and Respiration  907
     45 The Nervous System  939
     46 Sensory Systems  969
     47 The Endocrine System  991
     48 The Immune System  1013
     49 Maintaining the Internal Environment  1039
     50 Sex and Reproduction  1061
     51 Vertebrate Development  1081
Part VIII Ecology and Behavior  1105
     52 Behavioral Biology  1105
     53 Population Ecology  1137
     54 Community Ecology  1161
     55 Dynamics of Ecosystems  1183
     56 The Biosphere  1203
     57 Conservation Biology  1227

Contents
Part I The Origin of Living Things
 1
The Science of Biology 1
     1.1 Biology is the science of life.
     1.2 Scientists form generalizations from observations.
     1.3 Darwin’s theory of evolution illustrates how science works.
     1.4 Four themes unify biology as a science.
2
The Nature of Molecules 19
     2.1 Atoms are natures building material.
     2.2 The atoms of living things are among the smallest.
     2.3 Chemical bonds hold molecules together.
     2.4 Water is the cradle of life.
3
The Chemical Building Blocks of Life 35
     3.1 Molecules are the building blocks of life.
     3.2 Proteins perform the chemistry of the cell.
     3.3 Nucleic acids store and transfer genetic information.
     3.4 Lipids make membranes and store energy.
     3.5 Carbohydrates store energy and provide building materials.
4
The Origin and Early History of Life 61
     4.1 All living things share key characteristics.
     4.2 There is considerable disagreement about the origin of life.
     4.3 There are many hypotheses about the origin of cells.
     4.4 Cells became progressively more complex as they evolved.
     4.5 Scientists are beginning to take the possibility of extraterrestrial life seriously.

Part II  Biology of the Cell
5
Cell Structure 79
     5.1 All organisms are composed of cells.
     5.2 Eukaryotic cells are more structurally complex than prokaryotic cells.
     5.3 Take a tour of a eukaryotic.
     5.4 Not all eukaryotic cells are the same.
6
Membranes 105
     6.1 Biological membranes are fluid layers of lipid.
     6.2 Proteins embedded within cell membranes determine their character.
     6.3 Passive transport across membranes moves down the concentration gradient.
     6.4 Bulk transport utilizes endocytosis.
     6.5 Active transport across membranes requires energy.
7
Cell-Cell Interactions 125
     7.1 Cells signal one another with chemicals.
     7.2 Proteins in the cell and on its surface receive signals from other cells.
     7.3 Follow the journey of information into the cell.
     7.4 Cell surface proteins mediate cell-cell interactions.
8
Energy and Metabolism 143
     8.1 The laws of thermodynamics describe how energy changes.
     8.2 Enzymes are biological catalysts.
     8.3 ATP is the energy currency of life.
     8.4 Metabolism is the chemical life of a cell.
9
How Cells Harvest Energy 159
     9.1 Cells harvest the energy in chemical bonds.
     9.2 Cellular respiration oxidizes food molecules.
     9.3 Catabolism of proteins and fats can yield considerable energy.
     9.4 Cells can metabolize food without oxygen.
     9.5 The stages of cellular respiration evolved over time.
10
Photosynthesis 185
     10.1 What is photosynthesis?
     10.2 Learning about photosynthesis: An experimental journey.
     10.3 Pigments capture energy from sunlight.
     10.4 Cells use the energy and reducing power captured by the light-dependent reactions to make organic molecules.
11
How Cells Divide 207
     11.1 Prokaryotes divide far more simply than do eukaryotes.
     11.2 The chromosomes of eukaryotes are highly ordered structures.
     11.3 Mitosis is a key phase of the cell cycle.
     11.4 The cell cycle is carefully controlled.

Part III  Genetic and Molecular Biology
12
Sexual Reproduction and Meiosis 227
     12.1 Meiosis produces haploid cells from diploid cells.
     12.2 Meiosis has unique features.
     12.3 The sequence of events during meiosis involves two nuclear divisions.
     12.4 The evolutionary origin of sex is a puzzle.
13
Patterns of Inheritance 241
     13.1 Mendel solved the mystery of heredity.
     13.2 Human genetics follows Mendelian principles.
     13.3 Genes are on chromosomes.
14
DNA: The Genetic Material 279
     14.1 What is the genetic material?
     14.2 What is the structure of DNA?
     14.3 How does DNA replicate?
     14.4 What is a gene?
15
Genes and How They Work 301
     15.1 The Central Dogma traces the flow of gene-encoded information.
     15.2 Genes encode information in three-nucleotide code words.
     15.3 Genes are first transcribed, then translated.
     15.4 Eukaryotic gene transcripts are spliced.
16
Gene Technology 319
     16.1 Molecular biologists can manipulate DNA to clone genes.
     16.2 Genetic engineering involves easily understood procedures.
     16.3 Biotechnology is producing a scientific revolution.
17
Genomes 343
     17.1 Genomes can be mapped both genetically and physically.
     17.2 Genome sequencing produces the ultimate physical map.
     17.3 Being more complex does not necessarily require more genes.
     17.4 Genomics is opening a new window of life.
18
Control of Gene Expression 361
     18.1 Gene expression is controlled by regulating transcription.
     18.2 Regulatory proteins read DNA without unwinding it.
     18.3 Prokaryotes regulate genes by controlling transcription initiation.
     18.4 Transcriptional control in eukaryotes operates at a distance.
19
Cellular Mechanisms of Development 381
     19.1 Development is a regulated process.
     19.2 Multicellular organisms employ the same basic mechanisms of development.
     19.3 Aging can be considered a developmental process.
20
Cancer Biology and Cell Technology 405
     20.1 Recombination alters gene location.
     20.2 Mutations are changes in the genetic message.
     20.3 Most cancer results from mutation of growth-regulating genes.
     20.4 Reproductive cloning of animals, once thought impossible, isn’t.
     20.5 Therapeutic cloning is a promising but controversial possibility.

Part IV  Evolution
21
Genes Within Populations 433
     21.1 Genes vary in natural populations.
     21.2 Why do allele frequencies change in populations?
     21.3 Selection can act on traits affected by many genes.
22
The Evidence for Evolution 453
     22.1 Evidence indicates that natural selection can produce evolutionary change.
     22.2 Fossil evidence indicated that evolution has occurred.
     22.3 Evidence for evolution can be found in other fields of biology.
     22.4 The theory of evolution has proven controversial.
23
The Origin of Species 471
     23.1 Species are the basic units of evolution.
     23.2 Species maintain their genetic distinctiveness through barriers to reproduction.
     23.3 We have learned a great deal about how species form.
     23.4 Clusters of species reflect rapid evolution.
24
Evolution of Genomes and Developmental Mechanisms 491
     24.1 Evolutionary history is written in genomes.
     24.2 Developmental mechanisms are evolving.

Part V  Diversity of Life on Earth
25
Systematics and the Phylogenetic Revolution 509
     25.1 Biologists name organisms in a systematic way.
     25.2 Scientists construct phylogenies to understand the evolutionary relationships among species.
     25.3 Phylogenetics is the basis of all comparative biology.
     25.4 All living organisms are grouped into one of a few major categories.
     25.5 Molecular data are revolutionizing taxonomy.
26
Viruses 531
     26.1 Viruses are stands of nucleic acid encased within a protein coat.
     26.2 Bacterial viruses exhibit two sorts of reproductive cycles.
     26.3 HIV is a complex animal virus.
     26.4 Nonliving infectious agents are responsible for many human diseases.
27
Prokaryotes 545
     27.1 Prokaryotes are the smallest and most numerous organisms.
     27.2 Prokaryotes exhibit considerable diversity in both structure and metabolism.
     27.3 Prokaryotes are more complex than commonly supposed.
     27.4 Prokaryotes are responsible for many diseases, but they also make important contributions to ecosystems.
28
Protists 561
     28.1 Eukaryotes probably arose by endosymbiosis.
     28.2 The kingdom Protista is by far the most diverse of any kingdom.
     28.3 Protists can be categorized into six groups.
29
Overview of Plant Diversity 579
     29.1 Plants have multicellular haploid and diploid stages in their life cycles.
     29.2 Nonvascular plants are relatively unspecialized but successful in many terrestrial environments.
     29.3 Seedless vascular plants have well-developed conducting tissues in their sporophytes.
     29.4 Seeds protect and aid in the dispersal of plant embryos.
30
Fungi 599
     30.1 The fungi share several key characteristics.
     30.2 There are four major groups of fungi.
     30.3 Fungi participate in many symbioses.
31
Overview of Animal Diversity 617
     31.1 Animals are multicellular heterotrophs without cell walls.
     31.2 Animals are a very diverse kingdom.
     31.3 The animal body plan has undergone many changes.
     31.4 The way we classify animals is being reevaluated.
32
Noncoelomate Invertebrates 633
     32.1 The classification of invertebrates is currently being reevaluated.
     32.2 The simplest animals are not bilaterally symmetrical.
     32.3 Acoelomates are solid worms that lack a body cavity.
     32.4 Pseudocoelomates have a simple body cavity.
33
Coelomate Invertebrates 651
     33.1 Mollusks were among the first coelomates.
     33.2 Annelids were the first segmented animals.
     33.3 Lophophorates appear to be a transitional group.
     33.4 Arthropods are the most diverse of all animal groups.
     33.5 Echinoderms are radially symmetrical as adults.
34
Vertebrates 683
     34.1 Attaching muscles to an internal framework greatly improves movement.
     34.2 Nonvertebrate chordates have a notochord but no backbone.
     34.3 The evolution of vertebrates involved invasions of sea, land, and air.
     34.4 Evolution among the primates has focused on brain size and locomotion.

Part VI  Plant Form and Function
35
Plant Form 729
     35.1 Meristems elaborate the plant body plan after germination.
     35.2 Plants have three basic tissues, each composed of several cell types.
     35.3 Root cells differentiate as they become distanced from the dividing root apical meristem.
     35.4 Stems are the backbone of the shoot, transporting nutrients and supporting the aerial plant organs.
     35.5 Leaves are adapted to support basic plant functions.
36
Vegetative Plant Development 755
     36.1 Plant embryo development establishes a basic body plan.
     36.2 The seed protects the dormant embryo from water loss.
     36.3 Fruit formation enhances the dispersal of seeds. 
     36.4 Germination initiates post-seed development.
37
Transport in Plants 767
     37.1 Water and minerals move upward through the xylem.
     37.2 Dissolved sugars and hormones are transported in the phloem.
38
Plant Nutrition 781
     38.1 Plants require a variety of nutrients in addition to the direct products of photosynthesis.
     38.2 Global change could alter the balance among photosynthesis, respiration, and use of nutrients acquired through the soil.
     38.3 Some plants have novel strategies for obtaining nutrients.
     38.4 Plants can remove harmful chemicals from the soil.
39
Plant Defense Responses 795
     39.1 Morphological and physiological features protect plants from invasion.
     39.2 Some plant defenses act by poisoning the invader.
     39.3 Some plants have coevolved with bodyguards.
     39.4 Systemic responses also protect plants from invaders.
40
Sensory Systems in Plants 807
     40.1 Plants respond to light.
     40.2 Plants respond to gravity.
     40.3 Plants respond to touch.
     40.4 Water and temperature elicit plant responses.
     40.5 The hormones that guide growth are keyed to the environment.
41
Plant Reproduction 831
     41.1 The environment influences reproduction.
     41.2 Flowers are highly evolved for reproducing.
     41.3 Many plants can clone themselves by asexual reproduction.
     41.4 How long do plants and plant organs live?

Part VII  Animal Form and Function
42
The Animal Body and How It Moves 855
     42.1 The bodies of vertebrates are organized into functional systems.
     42.2 Epithelial tissue forms membranes and glands.
     42.3 Connective tissues contain abundant extracellular material.
     42.4 Muscle tissue provides for movement, and nerve tissue provides for control.
     42.5 Coordinated efforts of organ systems are necessary for locomotion.
     42.6 Muscle contraction powers animal locomotion.
43
Fueling Body Activities: Digestion 887
     43.1 Animals employ a digestive system to prepare food for assimilation by cells.
     43.2 Food is ingested, swallowed, and transported to the stomach.
     43.3 The small and large intestines have very different functions.
     43.4 Neural, hormonal, and accessory organ regulation controls digestion.
     43.5 All animals require food energy and essential nutrients.
44
Circulation and Respiration 907
     44.1 Circulatory systems are the transportation highways of the animal body.
     44.2 The circulatory and respiratory systems evolved together in vertebrates.
     44.3 The cardiac cycle drives the cardiovascular system.
     44.4 Respiration has evolved to maximize the rate of gas diffusion.
     44.5 Mammalian breathing is a dynamic process.
45
The Nervous System 939
     45.1 The nervous system consists of neurons and supporting cells.
     45.2 Nerve impulses are produced on the axon membrane.
     45.3 Neurons form junctions called synapses with other cells.
     45.4 The central nervous system consists of the brain and spinal cord.
     45.5 The peripheral nervous system consists of sensory and motor neurons.
46
Sensory Systems 969
     46.1 Animals employ a wide variety of sensory receptors.
     46.2 Mechanical and chemical receptors sense the body’s condition.
     46.3 Auditory receptors detect pressure waves in the air.
     46.4 Optic receptors detect light over a broad range of wavelengths.
     46.5 Some vertebrates use heat, electricity, or magnetism for orientation.
47
The Endocrine System 991
     47.1 Regulation is often accomplished by chemical messengers.
     47.2 Lipophilic and polar hormones regulate their target cells by different means.
     47.3 The hypothalamus controls the secretions of the pituitary gland.
     47.4 Endocrine glands secrete hormones that regulate many body functions.
48
The Immune System 1013
     48.1 Many body’s most effective defenses are nonspecific.
     48.2 Specific immune defenses require the recognition of antigens.
     48.3 T cells organize attacks against invading microbes.
     48.4 B cells label specific cells for destruction.
     48.5 The immune system can be defeated.
49
Maintaining the Internal Environment 1039
     49.1 The regulatory systems of the body maintain homeostasis.
     49.2 The extracellular fluid concentration is constant in most vertebrates.
     49.3 The functions of the vertebrate kidney are performed by nephrons.
50
Sex and Reproduction 1061
     50.1 Animals employ both sexual and asexual reproductive strategies.
     50.2 The evolution of reproduction among the vertebrates has led to internalization of fertilization and development.
     50.3 Male and female reproductive systems are specialized for different functions.
51
Vertebrate Development 1081
     51.1 Fertilization is the initial event in development.
     51.2 Cell cleavage and the formation of a blastula set the stage for later development.
     51.3 Gastrulation forms the three germ layers of the embryo.
     51.4 Body architecture is determined during the next stages of embryonic development.
     51.5 Human development is divided into trimesters.

Part VIII  Ecology and Behavior
52
Behavioral Biology 1105
     52.1 Many behavioral patterns are innate.
     52.2 Learning influences behavior.
     52.3 Communication is a key element of many animal behaviors.
     52.4 Evolutionary forces shape behavior.
53
Population Ecology 1137
     53.1 Organisms must cope with a varied environment.
     53.2 Populations are individuals of the same species that live in the same place.
     53.3 Population dynamics depend critically upon age distribution.
     53.4 Life histories often reflect trade-offs between reproduction and survival. 
     53.5 Population growth is limited by the environment.
     53.6 The human population has grown explosively in the last three centuries.
54
Community Ecology 1161
     54.1 Biological communities are composed of species that occur together.
     54.2 Interactions among competing species shape ecological niches.
     54.3 Predation has ecological and evolutionary effects.
     54.4 Species within a community interact in many ways.
     54.5 Ecological succession may increase the species richness of communities.
55
Dynamics of Ecosystems 1183
     55.1 Chemicals cycle within ecosystems.
     55.2 Energy flows through ecosystems.
     55.3 Interactions occur among different trophic levels.
     55.4 Biodiversity promotes ecosystem stability.
56
The Biosphere 1203
     56.1 Climate shapes the character of ecosystems.
     56.2 Biomes are widespread terrestrial ecosystems.
     56.3 Aquatic ecosystems cover much of the earth.
     56.4 Human activity is placing the biosphere under increasing stress.
57
Conservation Biology 1227
     57.1 The new science of conservation biology is focused on conserving biodiversity.
     57.2 The extinction crisis is a result of many factors.
     57.3 Successful recovery efforts need to be multidimensional.
      
      Glossary  G-1
      Credits  C-1
      Index  I-1