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  1. Preface
  2. Unit 1. The Cellular Foundation of Life
    1. 1 Introduction to Biology
      1. Introduction
      2. 1.1 Themes and Concepts of Biology
      3. 1.2 The Process of Science
      4. Key Terms
      5. Chapter Summary
      6. Visual Connection Questions
      7. Review Questions
      8. Critical Thinking Questions
    2. 2 Chemistry of Life
      1. Introduction
      2. 2.1 The Building Blocks of Molecules
      3. 2.2 Water
      4. 2.3 Biological Molecules
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
    3. 3 Cell Structure and Function
      1. Introduction
      2. 3.1 How Cells Are Studied
      3. 3.2 Comparing Prokaryotic and Eukaryotic Cells
      4. 3.3 Eukaryotic Cells
      5. 3.4 The Cell Membrane
      6. 3.5 Passive Transport
      7. 3.6 Active Transport
      8. Key Terms
      9. Chapter Summary
      10. Visual Connection Questions
      11. Review Questions
      12. Critical Thinking Questions
    4. 4 How Cells Obtain Energy
      1. Introduction
      2. 4.1 Energy and Metabolism
      3. 4.2 Glycolysis
      4. 4.3 Citric Acid Cycle and Oxidative Phosphorylation
      5. 4.4 Fermentation
      6. 4.5 Connections to Other Metabolic Pathways
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
    5. 5 Photosynthesis
      1. Introduction
      2. 5.1 Overview of Photosynthesis
      3. 5.2 The Light-Dependent Reactions of Photosynthesis
      4. 5.3 The Calvin Cycle
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
  3. Unit 2. Cell Division and Genetics
    1. 6 Reproduction at the Cellular Level
      1. Introduction
      2. 6.1 The Genome
      3. 6.2 The Cell Cycle
      4. 6.3 Cancer and the Cell Cycle
      5. 6.4 Prokaryotic Cell Division
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    2. 7 The Cellular Basis of Inheritance
      1. Introduction
      2. 7.1 Sexual Reproduction
      3. 7.2 Meiosis
      4. 7.3 Errors in Meiosis
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
    3. 8 Patterns of Inheritance
      1. Introduction
      2. 8.1 Mendel’s Experiments
      3. 8.2 Laws of Inheritance
      4. 8.3 Extensions of the Laws of Inheritance
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
  4. Unit 3. Molecular Biology and Biotechnology
    1. 9 Molecular Biology
      1. Introduction
      2. 9.1 The Structure of DNA
      3. 9.2 DNA Replication
      4. 9.3 Transcription
      5. 9.4 Translation
      6. 9.5 How Genes Are Regulated
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
    2. 10 Biotechnology
      1. Introduction
      2. 10.1 Cloning and Genetic Engineering
      3. 10.2 Biotechnology in Medicine and Agriculture
      4. 10.3 Genomics and Proteomics
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
  5. Unit 4. Evolution and the Diversity of Life
    1. 11 Evolution and Its Processes
      1. Introduction
      2. 11.1 Discovering How Populations Change
      3. 11.2 Mechanisms of Evolution
      4. 11.3 Evidence of Evolution
      5. 11.4 Speciation
      6. 11.5 Common Misconceptions about Evolution
      7. Key Terms
      8. Chapter Summary
      9. Visual Connection Questions
      10. Review Questions
      11. Critical Thinking Questions
    2. 12 Diversity of Life
      1. Introduction
      2. 12.1 Organizing Life on Earth
      3. 12.2 Determining Evolutionary Relationships
      4. Key Terms
      5. Chapter Summary
      6. Visual Connection Questions
      7. Review Questions
      8. Critical Thinking Questions
    3. 13 Diversity of Microbes, Fungi, and Protists
      1. Introduction
      2. 13.1 Prokaryotic Diversity
      3. 13.2 Eukaryotic Origins
      4. 13.3 Protists
      5. 13.4 Fungi
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    4. 14 Diversity of Plants
      1. Introduction
      2. 14.1 The Plant Kingdom
      3. 14.2 Seedless Plants
      4. 14.3 Seed Plants: Gymnosperms
      5. 14.4 Seed Plants: Angiosperms
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    5. 15 Diversity of Animals
      1. Introduction
      2. 15.1 Features of the Animal Kingdom
      3. 15.2 Sponges and Cnidarians
      4. 15.3 Flatworms, Nematodes, and Arthropods
      5. 15.4 Mollusks and Annelids
      6. 15.5 Echinoderms and Chordates
      7. 15.6 Vertebrates
      8. Key Terms
      9. Chapter Summary
      10. Visual Connection Questions
      11. Review Questions
      12. Critical Thinking Questions
  6. Unit 5. Animal Structure and Function
    1. 16 The Body’s Systems
      1. Introduction
      2. 16.1 Homeostasis and Osmoregulation
      3. 16.2 Digestive System
      4. 16.3 Circulatory and Respiratory Systems
      5. 16.4 Endocrine System
      6. 16.5 Musculoskeletal System
      7. 16.6 Nervous System
      8. Key Terms
      9. Chapter Summary
      10. Visual Connection Questions
      11. Review Questions
      12. Critical Thinking Questions
    2. 17 The Immune System and Disease
      1. Introduction
      2. 17.1 Viruses
      3. 17.2 Innate Immunity
      4. 17.3 Adaptive Immunity
      5. 17.4 Disruptions in the Immune System
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    3. 18 Animal Reproduction and Development
      1. Introduction
      2. 18.1 How Animals Reproduce
      3. 18.2 Development and Organogenesis
      4. 18.3 Human Reproduction
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
  7. Unit 6. Ecology
    1. 19 Population and Community Ecology
      1. Introduction
      2. 19.1 Population Demographics and Dynamics
      3. 19.2 Population Growth and Regulation
      4. 19.3 The Human Population
      5. 19.4 Community Ecology
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    2. 20 Ecosystems and the Biosphere
      1. Introduction
      2. 20.1 Waterford's Energy Flow through Ecosystems
      3. 20.2 Biogeochemical Cycles
      4. 20.3 Terrestrial Biomes
      5. 20.4 Aquatic and Marine Biomes
      6. Key Terms
      7. Chapter Summary
      8. Visual Connection Questions
      9. Review Questions
      10. Critical Thinking Questions
    3. 21 Conservation and Biodiversity
      1. Introduction
      2. 21.1 Importance of Biodiversity
      3. 21.2 Threats to Biodiversity
      4. 21.3 Preserving Biodiversity
      5. Key Terms
      6. Chapter Summary
      7. Visual Connection Questions
      8. Review Questions
      9. Critical Thinking Questions
  8. A | The Periodic Table of Elements
  9. B | Geological Time
  10. C | Measurements and the Metric System
  11. Index
acoelomate
without a body cavity
Actinopterygii
ray-finned fishes
amniote
a clade of animals that possesses an amniotic egg; includes reptiles (including birds) and mammals
amoebocyte
an amoeba-like cell of sponges whose functions include distribution of nutrients to other cells in the sponge
Amphibia
frogs, salamanders, and caecilians
ampulla of Lorenzini
a sensory organ that allows sharks to detect electromagnetic fields produced by living things
Annelida
a phylum of worm-like animals with metamerism
anthropoids
a clade consisting of monkeys, apes, and humans
Anura
frogs
Apoda
caecilians
Arthropoda
a phylum of Ecdysozoa with jointed appendages and segmented bodies
asymmetrical
having no plane of symmetry
bilateral symmetry
a type of symmetry in which there is only one plane of symmetry that creates two mirror-image sides
body plan
the shape and symmetry of an organism
brachiation
swinging through trees
budding
a form of asexual reproduction that occurs through the growth of a new organism as a branch on an adult organism that breaks off and becomes independent; found in plants, sponges, cnidarians, and some other invertebrates
caecilian
a legless amphibian that belongs to clade Apoda
Cephalochordata
a chordate clade whose members possess a notochord, dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail in the adult stage
cephalothorax
a fused head and thorax
chaeta
a chitinous projection from the cuticle found in annelids
chelicerae
a modified first pair of appendages in subphylum Chelicerata
chitin
a tough nitrogen-containing polysaccharide found in the cuticles of arthropods and the cell walls of fungi
choanocyte
a cell type unique to sponges with a flagellum surrounded by a collar used to maintain water flow through the sponge, and capture and digest food particles
Chondrichthyes
jawed fishes with paired fins and a skeleton made of cartilage
Chordata
a phylum of animals distinguished by their possession of a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail at some point during their development
clitellum
a specialized band of fused segments in some annelids, which aids in reproduction
Cnidaria
a phylum of animals that are diploblastic and have radial symmetry and stinging cells
cnidocyte
a specialized stinging cell found in Cnidaria
coelom
a lined body cavity derived from mesodermal embryonic tissue
complete digestive system
a digestive system that opens at one end, the mouth, and exits at the other end, the anus, and through which food normally moves in one direction
craniate
a proposed clade of chordates that includes all groups except the tunicates and lancelets
Crocodilia
crocodiles and alligators
ctenidia
specialized gills in mollusks
cutaneous respiration
gas exchange through the skin
deuterostome
describing an animal in which the blastopore develops into the anus, with the second opening developing into the mouth
dioecious
having separate male and female sexes
diphyodont
refers to the possession of two sets of teeth in a lifetime
diploblast
an animal that develops from two embryonic germ layers
dorsal hollow nerve cord
a hollow, tubular structure derived from ectoderm, which is located dorsal to the notochord in chordates
down feather
feather specialized for insulation
Echinodermata
a phylum of deuterostomes with spiny skin; exclusively marine organisms
epidermis
the layer of cells that lines the outer surface of an animal
eucoelomate
describing animals with a body cavity completely lined with mesodermal tissue
eutherian mammal
a mammal with a complex placenta, which connects a fetus to the mother; sometimes called placental mammals
extracellular digestion
a form of digestion, the breakdown of food, which occurs outside of cells with the aid of enzymes released by cells
fragmentation
a form of asexual reproduction in which a portion of the body of an organism breaks off and develops into a living independent organism; found in plants, sponges, and some other invertebrates
frog
a tail-less amphibian that belongs to clade Anura
gastrodermis
the layer of cells that lines the gastrovascular cavity of cnidarians
gastrovascular cavity
the central cavity bounded by the gastrodermis in cnidarians
gemmule
a structure produced by asexual reproduction in freshwater sponges that is able to survive harsh conditions
germ layer
a collection of cells formed during embryogenesis that will give rise to future body tissues
gnathostome
a jawed fish
hagfish
an eel-like jawless fish that lives on the ocean floor and is a scavenger
hemocoel
the internal body cavity seen in arthropods
heterodont teeth
different types of teeth modified by different purposes
intracellular digestion
the digestion of matter brought into a cell by phagocytosis
lamprey
a jawless fish characterized by a toothed, funnel-like, sucking mouth
lancelet
a member of Cephalochordata; named for its blade-like shape
lateral line
the sense organ that runs the length of a fish’s body, used to detect vibration in the water
Lophotrochozoa
a clade of invertebrate organisms that is a sister group to the Ecdysozoa
madreporite
a pore for regulating entry and exit of water into the water vascular system
mammal
one of the groups of endothermic vertebrates that possess hair and mammary glands
mammary gland
in female mammals, a gland that produces milk for newborns
mantle
a specialized epidermis that encloses all visceral organs and secretes shells in mollusks
marsupial
one of the groups of mammals that includes the kangaroo, koala, bandicoot, Tasmanian devil, and several other species; young develop within a pouch
medusa
a free-floating cnidarian body plan with a mouth on the underside and tentacles hanging down from a bell
mesoglea
the non-living, gel-like matrix present in between ectoderm and endoderm in cnidarians
mesohyl
the collagen-like gel containing suspended cells that perform various functions in sponges
metamerism
having a series of body structures that are similar internally and externally, such as segments
Mollusca
a phylum of protostomes with soft bodies and no segmentation
monoecious
having both sexes in one body, hermaphroditic
monotreme
an egg-laying mammal
Myxini
hagfishes
nacre
a calcareous secretion produced by bivalve mollusks to line the inner side of shells as well as to coat foreign particulate matter
nematocyst
the harpoon-like organelle within a cnidocyte with a pointed projectile and poison to stun and entangle prey
Nematoda
a phylum of worms in Ecdysozoa commonly called roundworms containing both free-living and parasitic forms
notochord
a flexible, rod-shaped structure that is found in the embryonic stage of all chordates and in the adult stage of some chordates
osculum
the large opening in a sponge body through which water leaves
Osteichthyes
bony fishes
ostracoderm
one of the earliest jawless fishes covered in bone
Petromyzontidae
the clade of lampreys
pharyngeal slit
an opening in the pharynx
pneumatic bone
an air-filled bone
polyp
the stalk-like, sessile life form of a cnidarians with mouth and tentacles facing upward, usually sessile but may be able to glide along a surface
Porifera
a phylum of animals with no true tissues, but a porous body with a rudimentary endoskeleton
post-anal tail
a muscular, posterior elongation of the body extending beyond the anus in chordates
Primates
includes lemurs, tarsiers, monkeys, apes, and humans
prosimians
a group of primates that includes bush babies of Africa, lemurs of Madagascar, and lorises, pottos, and tarsiers of southeast Asia
protostome
describing an animal in which the mouth develops first during embryogenesis and a second opening developing into the anus
pseudocoelomate
an animal with a coelom that is not completely lined with tissues derived from the mesoderm as in eucoelomate animals
radial symmetry
a type of symmetry with multiple planes of symmetry all cross at an axis through the center of the organism
radula
a tongue-like scraping organ with chitinous ornamentation found in most mollusks
salamander
a tailed amphibian that belongs to the clade Urodela
Sarcopterygii
lobe-finned fishes
sebaceous gland
in mammals, a skin gland that produce a lipid mixture called sebum
Sphenodontia
the reptilian clade that includes the tuataras
spicule
a short sliver or spike-like structure, in sponges, they are formed of silicon dioxide, calcium carbonate, or protein, and are found in the mesohyl
spiracle
a respiratory openings in insects that allow air into the tracheae
spongocoel
the central cavity within the body of some sponges
Squamata
the reptilian clade of lizards and snakes
stereoscopic vision
two overlapping fields of vision from the eyes that produces depth perception
sudoriferous gland
a gland in mammals that produces sweat and scent molecules
swim bladder
in fishes, a gas filled organ that helps to control the buoyancy of the fish
tadpole
the larval stage of a frog
Testudines
turtles
tetrapod
a four-footed animal; includes amphibians, reptiles, birds, and mammals
trachea
in some arthropods, such as insects, a respiratory tube that conducts air from the spiracles to the tissues
triploblast
an animal that develops from three germ layers
tunicate
a sessile chordate that is a member of Urochordata
Urochordata
the clade composed of the tunicates
Urodela
salamanders
vertebral column
a series of separate bones that surround the spinal cord in vertebrates
water vascular system
a system in echinoderms in which water is the circulatory fluid
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