The Ultimate Vampire Resource and Directory

, Maria

Period 6

Evolution Vocabulary

Chapter 15

1. Evolution- change in a kind of organism over-time; process by which modern organisms have descended from ancient organisms

2. Theory- well-tested explanation that unifies a broad range of observations

3. Fossil- preserved remains or evidence of an ancient organism

4. Artificial Selection- selection by humans for breeding of useful traits from the natural variation among different organisms

5. Struggle for Existence- competition among members of a species for food, living space, and the other necessities of life

6. Fitness- ability of an organism to survive and reproduce in its environment

7. Adaptation- inherited characteristic that increases an organisms chance of survival

8. Survival of the Fittest- process by which individuals that are better suited to their environment survive and reproduce most successfully; also called natural selection

9. Natural Selection- process by which individuals that are better suited to their environment survive and reproduce most successfully; also called survival of the fittest

10. Descent with Modification- principle that each living species has descended, with changes, from other species over time

11. Common Descent- principle that all living things were derived from common ancestors

12. Homologous Structure- structures that have different mature forms in different organisms but develop from the same embryonic tissues

13. Vestigial Organ- organ that serves no useful function to an organism

Chapter 16

14. Gene Pool- combined genetic information of all the members of a particular chromosome

15. Relative Frequency- number of times an allele occurs in a gene pool compared with the number of times other alleles occur

16. Single-Gene Trait- trait controlled by a single gene that has two alleles

17. Polygenic Trait- trait controlled by two or more genes

18. Directional Selection- form of natural selection in which the entire curve moves; occurs when individuals at one end of a distribution curve have higher fitness than individuals in the middle or at the other end of the curve

19. Stabilizing Selection- form of natural selection by which the center of the curve remains in its current position; occurs when individuals near the center of a distribution curve have higher fitness than individuals at either end

20. Disruptive Selection- form of natural selection in which a single curve splits into two; occurs when individuals at the upper and lower ends of a distribution curve have higher fitness than individuals near the middle

21. Genetic Drift- random change in allele frequencies as a result of a migration of a small subgroup of a population

22. Hardy-Weinberg Principle- principle that allele frequencies in a population will remain constant unless one or more factors cause the frequencies to change

23. Genetic Equilibrium- situation in which allele frequencies remain constant

24. Speciation- formation of a new species

25. Reproductive Isolation- separation of species or populations so that they cannot interbreed and produce fertile offspring

26. Behavioral Isolation- form of reproductive isolation in which two populations have differences in courtship rituals or other types of behavior that prevent them from interbreeding

27. Geographic Isolation- form of reproductive isolation in which two populations save separated physically by geographic barriers such as rivers, mountains, or stretches of water

28. Temporal isolation- form of reproductive isolation in which two populations reproduce at different times

Chapter 17

29. Paleontologist- scientist who studies fossils

30. Fossil Record- information about past life, including the structure of organisms, what they ate, what ate them, in what environment they lived, and the order in which they lived

31. Extinct- term used to refer to a species that has died out

32. Relative Dating- method of determining the age of a fossil by comparing its placement with that of fossils in other layers of rock

33. Index Fossil- distinctive fossil used to compare the relative ages of fossils

34. Half-Life- length of time required for half of the radioactive atoms in a sample to decay

35. Radioactive Dating- technique in which scientists calculate the age of a sample based on the amount of remaining radioactive isotopes it contains

36. Geologic Time Scale- scale used by paleontologists to represent evolutionary time

37. Era- one of several subdivisions of the time between the Precambrian and the present

38. Period- unit of time into which eras are subdivided

39. Proteinoid Microsphere- tiny bubble, formed of large organic molecules, that has some characteristics of a cell

40. Microfossil- microscopic fossil

41. Endosymbiotic Theory- theory that eukaryotic cells formed from a symbiosis among several different prokaryotic organisms

42. Mass Extinction- event in which many types of living things become extinct at the same time

43. Macroevolution- large-scale evolutionary changes that take place over long periods of time

44. Adaptive Radiation- process by which a single species or small group of species evolves into several different forms that live in different ways; rapid growth in diversity of a group of organisms

45. Convergent Evolution- process by which unrelated organisms independently evolve similarities when adapting to similar environments

46. Coevolution- process by which two species evolve in response to changes in each other

47. Punctuated Equilibrium- pattern of evolution in which long stable periods are interrupted by more rapid change

Chapter 18

48. Taxonomy- discipline of classifying organisms and assigning each organism a universally accepted name

49. Binomial Nomenclature- classification system in which each species is assigned a two-part scientific name

50. Genus- group of closely related species, and the first part of the scientific name in binomial nomenclature

51. Taxon- group of level of organization into which organisms are classified

52. Family- group of genera that share many characteristics

53. Order- Groups of similar families

54. Class- Group of similar orders

55. Phylum- Group of closely related classes

56. Kingdom- Large taxonomic group, consisting of closely related phyla

57. Phylogeny- the study of evolutionary relationships among organisms

58. Evolutionary Classification- method of grouping organisms together according to their evolutionary history

59. Derived Character- characteristic that appears in recent parts of a lineage, but not in its older members

60. Cladogram- diagram that shows the evolutionary relationships among a group of organisms

61. Molecular Clock- model that uses DNA comparisons to estimate the length of time that two species have been evolving independently

62. Domain- most inclusive taxonomic category; larger than a kingdom

63. Bacteria- domain of unicellular prokaryotes that have cell walls containing peptidoglycan

64. Eubacteria- kingdom of unicellular prokaryotes whose cell walls are made up of peptidoglycan

65. Archea- domain of unicellular prokaryotes that have cell walls that do not contain peptidoglycan

66. Archaebacteria- kingdom of unicellular prokaryotes whose cell walls do not contain peptidoglycan

67. Eukarya- domain of all organisms whose cells have nuclei, including protists, plants, fungi, and animals

68. Protista- kingdom composed of eukaryotes that are not classified as plants, animals, or fungi

69. Fungi- kingdom composed of heterotrophs; many obtain energy and nutrients from dead organic matter

70. Plantae- kingdom of multicellular photosynthetic autotrophs that have cell walls containing cellulose

71. Animalia- kingdom of multicellular eukaryotic heterotrophs whose cells do not have cell walls

Chapter 32

72. Mammary Gland- gland in mammals that produces milk to nourish the young

73. Subcutaneous Fat- Layer of fat cells beneath the skin that helps conserve body heat

74. Rumen- stomach chamber in cows and related animals in which newly swallowed plant food is stored and processed

75. Diaphragm- Large, flat muscle at the bottom of the chest cavity that helps with breathing

76. Cerebral Cortex- outer layer of the cerebrum of a mammal’s brain; center of thinking and other complex behavior

77. Monotreme- egg-laying mammal

78. Marsupial- mammal which bears live young that complete their development in an external pouch

79. Placenta- organ in placental mammals through which nutrients, oxygen, carbon, carbon dioxide, and wastes are exchanged between embryo and mother

80. Binocular Vision- ability to merge visual images from both eyes, which provides depth perception and a three-dimensional view of the world

81. Prosimian- small, nocturnal primate that has large eyes for seeing in the dark

82. Anthropoid- primate group made up of humans, apes, and most monkeys

83. Prehensile- term used to refer to a long tail that can grasp branches

84. Hominoid- anthropoid group that includes apes and humans

85. Hominid- primate that walks upright, has opposable thumbs, and possesses a large brain; only living members are humans

86. Bipedal- term used to refer to two-footed locomotion

87. Opposable Thumb- thumb that enables a grasping objects and using tools

Chapter 33

88. Notochord- long supporting rod that runs through a chordate’s body just below the nerve chord

89. Adaptive Radiation- process by which a single species or small group of species evolves into several different forms that live in different ways; rapid growth in the diversity of a group of organisms

90. Ectotherm- animal that relies on interactions with the environment to help it control its body temperature

91. Endotherm- animal that generates its own body heat and controls its body temperate from within

92. Alveolus- tiny air sac that provides surface area for gas exchange to occur





Chapter 34

93. Behavior- the way an organism reacts to change in its internal condition or external environment

94. Stimulus- a signal to which an organism responds

95. Response- single, specific reaction to a stimulus

96. Innate Behavior- instinct, or inborn behavior; behavior that appears in a fully functional form the first time it is performed

97. Learning- alterations in behavior as a result of experience; also called acquired behavior

98. Habituation- learning process to a repetitive stimulus that neither rewards nor harms it

99. Classical Conditioning- learning process in which an animal makes a mental connection between a stimulus and some kind of reward or punishment

100. Operant Conditioning- learning process in which an animal learns to behave in a certain way through repeated practice in order to receive a reward to avoid punishment; also called trial and error learning

101. Insight Learning- also called reasoning; learning process in which an animal applies something it has already learned to a new situation with a period of trial and error

102. Imprinting- learning based on early experience; once imprinting has occurred, the behavior cannot be changed

103. Migration- periodic movement and return of animals from one place to another

104. Circadian Rhythm- behavioral cycle that occurs in a daily pattern

105. Courtship- type of behavior in which an animal sends out stimuli in order attract a member of the opposite sex

106. Territory- specific area occupied and protected by an animal or group of animals

107. Aggression- threatening behavior that one animal uses to gain control over another

108. Communication- passing of information from one organism to another

109. Language- system of communication that combines sounds, symbols, or gestures according to a set of rules about word order and meaning

Chapter 31

110. Ectotherm- animal that relies on interactions with the environment to help it control body temperature

111. Amniotic Egg- egg composed of shell and membranes that create a protected environment in which the embryo can develop out of the water

112. Carapace- in crustaceans, the part of the exoskeleton that covers the cephalothorax; in turtles and tortoises, the dorsal part of the shell

113. Platron- ventral part of a turtle’s or tortoise’s shell

114. Feather- structure made mostly of protein that develops from a pit in a birds skin

115. Endotherm- animal that generates its own body heat and controls its body temperature from within

116. Crop- in earthworms, part of the digestive system in which food can be stored; in birds, structure at the lower end of the esophagus in which food is stored and moistened

117. Gizzard- in earthworms, part of the digestive system, in which food is ground into smaller pieces; in birds, a muscular organ that helps in the mechanical breakdown of food

118. Air Sac- one of several sacs attached to a birds lungs into which air moves when a bird inhales; allows for the one-way flow of air through the respiratory system

Chapter 30

119. Chordate- member of the phylum Chrodata; animal that has, for at least some stage of its life, a dorsal hallow nerve cord, a notochord, pharyngeal pouches, and a muscular tail

120. Notochord- long supporting rod that runs through a chordate’s body just below the nerve chord

121. Pharyngeal Pouch- one of a pair of structures in the throat (pharynx) region of a chordate

122. Vertebra- individual segment of the backbone; encloses and protects the spinal cord

123. Cartilage- strong connective tissue that supports the body and is softer and more flexible than bone

124. Atrium- upper chamber of the heart that receives and holds blood that is about to enter the ventricle

125. Ventricle- lower chamber of the heart that pumps blood out of the heart

126. Cerebrum- area of the brain responsible for all voluntary activites of the body

127. Cerebellum- region of the brain that coordinates body movements

128. Medulla Oblongata- area of the brain that controls the functioning of many internal organs

129. Lateral Line System- sensitive receptor system that enables fish to detect gentle currents and vibrations in the water

130. Swim Bladder- internal gas-filled organ in many bony fishes that adjusts their buoyancy

131. Oviparous- term used to refer to animals whose eggs hatch outside the mother’s body

132. Ovoviviparous- term used to refer to animals whose young are born alive after developing in eggs inside the mother’s body

133. Viviparous- term used to refer to animals that bear live young that are nourished directly by the mother’s body as they develop

134. Cloaca- a muscular cavity at the end of the large intestine through which digestive wastes, urine, and eggs or sperm leave the body