Bio exam 3.txt

Card Set Information

Bio exam 3.txt
2013-07-21 19:11:50
bio exam

bio exam 3
Show Answers:

  1. Why Study evolution? (5 points)
  2. Diseases
    agriculture and industry
  3. Darwin's 3 propositions for theory of evolution through natural selection
  4. 1. species change over time
    2. dif species may have common ancestor. 3. Species change because of natural selection.
  5. 3 things required for natural selection
  6. a. population must have variation in a trait. b. said trait must be heritable. c. trait must impact individual's reproductive success.
  7. T/F: evolution and natural selection are synonymous
  9. blue brown is to ______ as eye color is to ______.
  10. trait/character
  11. Fixed action pattern
  12. an instinctive response triggered by simple stimuli.
  13. 4 OTHER points to dawins theory
  14. 1. without variation
    natural selection can't occur.; 2. natural selection only acts on heritable traits. 3. heritable traits may be more or les beneficial depending on circumstances at hand (i.e. changes in environment) 4. only populations evolve. individuals do NOT .
  15. 5 assumptions of HW eq
  16. 1. no mutations. 2. no selection. 3. infinitely large population 4. no gene flow (migration) between the populations. 5. no random mating.
  17. What did darwin note about individuals and their parents?
  18. More individuals are born than can surivive to reproduce
    & iindividuals resemble their parents but are not exactly the same.
  19. If an average phenotype is most fit _______ will occur
  20. stabilizing selection
  21. if one extreme phenotype is most fit________ selection will ocur
  22. directional
  23. If both extreme phenotypes are most fit
    _________ selection will occur.
  24. disruptive
  25. gene flow can _______ genetic variation but it CANNOT create it from scratch
  26. introduce
  27. This occurs when one allele is lost and the other becomes the only one present in the population
  28. fixation
  29. Refers to genetic additions to or substractions from a population resulting from the movement of fertile individuals or gametes
  30. gene flow
  31. two factors that impact gene flow:
  32. number of migrants
  33. size of population
  34. occurs when individuals are more likely to maet when they have traits in common
  35. assortative mating
  36. this type of mating causes heterozygous genotypes to decrease in f and homozygous to iincrease in frequency
  37. assortative mating
  38. this kind of mating is the basis for sexual selection
  39. assortative
  40. this type of selection involves the selection for advantageous traits that make individuals of one sex more atractive to that of the other
  41. male competition between members of the same sex over acces to mates
  42. intrasexual selection
  43. types of adaptations that result from intrasexual selection
  44. sneaker males and mate guarding.
  45. Females tend to choose males based on 3 observable traits
  46. 1. direct benefits. 2. indicia of health or longevity aka 'good genes'. 3. arbitrary signs of male quality (penis preference)
  47. a condition in which males and females have gametes of different sizes (e.g. egg and sperm)
  48. anisogamy
  49. this is a type of selection that occurs when a phenotype's fitness depends on how common it is in the population
  50. frequency-dependent selection
  51. two types of frequency dependent selection
  52. positive and negative
  53. this occurs when most common pheotype is favored in the population.
  54. positive frequency dependent selection
  55. this type of selection occurs when rare phenotypes are favored in the population
  56. negative frequency dependent selection.
  57. different kinds of mutations (2)
  58. synonymous and nonsynonymous substitutions
  59. when rate of NSS > rate of SS
  60. positive selection and the resulting amino scid residue changes
  61. when rate of NSS = ate of SS
  62. neutral selection genetic drift is randomly changing
  63. When NSS < SS
  64. purifying selection. weeding out harmful alleles and resisting changes in corresponding amino acid residues.
  65. disadvantages of sexual reproduction (3)
  66. 1. recombintion can separate adaptive gene combinations. 2. sex reproeduction reduces reproductive rates. 3. reduces rate of gene transfer between females and offspring
  67. Some potential advantages that could have driven the evolution of sexual reproduction
  68. -recombination could separate deleterious gene combinations and eventually make them disappear. - can repair damaged DNA - new combinations of alleles on which selection can act
  69. A key disadvantage for asexual reproduction (muller's ratchet)
  70. no way to elimiate deleterious mutations
  71. in this type of gene transfer
    bacteria pick up fragments of dna directly from the environment
  72. transformation
  73. in this type of gene transfer
    DNA fragments are transferred from one bacterium to another by a virus.
  74. transduction
  75. In this type of gene transfer
    DNA is passed from one bacterium to another via a physical connection
  76. conjugation
  77. When is directional selection most likely
  78. when a gene has duplicated. this way
    the original gene is free to serve its original function. when the entire genome is duplicated
  79. This is a group of homologous genes that have related functions
  80. gene family
  81. 2 problems with morphological series concept
  82. members of same species may not look alike
    members of different sepecies may look alike
  83. 3 problems with biological sepcies concept
  84. does not apply to asexual organisms
    cannot be applied to extinct organisms
  85. According to this model
    something happens to subdivide a population into two isolated groups that evolve independently
  86. Dobzhansky-Muller model
  87. two major causes of sympatric selection
  88. disruptive selection and polyploidy
  89. This type of species refer to species that are in the process of diverging into seperate species but can currently interbreed
  90. incipient species
  91. When this happens
    populations may interbreed to a point that the formely separate sppecies become a single parent species again
  92. merger
  93. 2 forms of repuoductive barriers
  94. prezygotic and postzygotic isolating mechanisms
  95. Types of prezygoic isolating mechanisms (5)
  96. mechanical
  97. natural selection tendds to favor _____ isolating mechanisms rather than _____ isolating mechanisms.
  98. The end goal when constructing evolutionary histories is to identify monophyletic ______.
  99. clades.
  100. when we construct phylogenetic trees
    we try to group taxa with __ traits
  101. homologous
  102. Traits that are shared NOT due to a common evolutionary history but rather becaues of convergent evolution or evolutionary reversals.
  103. _________'s system of binomial nomenclature
  104. Linneau's
  105. King Phillip Came Over For Good Sex
  106. Kingdom
  107. 3 steps for building phylogenetic tree
  108. 1. identify taxa you want to study 2. Gather your data 3. Interpret data and build phylogeny