Bio Exam 2

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Bio Exam 2
2012-03-05 22:21:37

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  1. Mean annual air temperature decreases about ____ degrees C for every degree of latitude increase
  2. Intertropical Convergence Zone (ITCZ)
    Where the air masses from north and south meet
  3. Where air rises, rain is more/less likely to occur
    The great deserts occur at what latitudes?
    • More
    • 30 degrees N and S of equator
  4. Biome
    An environment defined by its climatic and geographic attributes and characterized by its dominant plants
  5. Tropical Savanna
    dominated by grasses and scattered trees; maintained by periodic droughts, and fire. Little rain in winter, but heavy in summer. Supports large grazing and browsing mammals and large predators.
  6. Temperate Grassland
    maintained by seasonal drought, occasional fire, and grazing by large animals. Much of this biome has been converted to agriculture. Rich in species; grasses, sedges, and forbs.
  7. Tropical Evergreen Rainforest
    equatorial regions with high rainfall; very high species diversity. Up to 500 tree species per km2. Also highest overall productivity. Most nutrients are tied up in vegetation; soils are poor.
  8. Chaparral
    On western sides of continents with cool ocean currents offshore. Winters cool and wet, summers warm and dry. Tough, evergreen shrubs dominate; adapted to fire.
  9. Temperate Deciduous Forest
    Precipitation is distributed evenly, but temperatures fluctuate dramatically. Forests dominated by deciduous trees that lose leaves during the cold season. Temperate forests with the most species were not covered by glaciers during the Pleistocene.
  10. Temperate Evergreen Forest
    coasts of continents, mid to high latitudes. Mild wet winters, Cool, dry summers.
  11. Boreal Forest
    northern latitudes or moderate elevations; cold winters. Dominated by evergreens Have only a few tree species.
  12. Arctic and Alpine Tundra
    Vegetation is low-growing perennials, underlain by permafrost soils, can be wet because of poor drainage. Animals migrate or go dormant for much of the year.
  13. Rain Shadow
    Dry areas on leeward side of mountains
  14. Biogeography
    study of distribution patterns of populations, species, and ecological communities.
  15. Continental Drift
    •Continental drift was proposed by Alfred Wegener in 1912, but was not taken seriously until geological evidence was amassed in the 1960s.

    •About 280 million years ago, the continents were united into one land mass called Pangaea.

    •During the Triassic period, the supercontinent Pangaea broke apart.

    •Many groups of terrestrial and freshwater organisms had already evolved.

    •Groups of organisms represented on widely separated continents today probably descend from ancestors that were present in Pangaea.
  16. Phylogenic Taxonomy
    • •The methods of phylogenetics have been applied to biogeographical questions.
    • •Phylogenetic trees are transformed into area phylogenies by replacing taxa names with place where the taxa live (or lived).
    • •For example, the ancestors of horses dispersed from North America to Asia, and then Africa.
  17. Biotic interchange
    Dispersal of species from different biotas into new regions when land masses fuse
  18. Vicariant Event
    Appearance of a physical barrier that splits the range of a species
  19. Dispersal
    if organisms cross an existing barrier and establish a population
  20. Freshwater environments encompass less than __% of the Earth's surface but are home to about __% of all aquatic species.
    • 3
    • 10
  21. Estuaries
    •transitional between freshwater and marine; often very productive. They have many unique species, and play an important role for other species as a conduit between marine and freshwater environments.
  22. Photic Zone
    Depth of ocean containing enough light for photosynthesis to occur
  23. Coastal Zone
    •extends from the shoreline to the edge of the continental shelf; characterized by shallow, well-oxygenated water and stable temperatures and salinities.

    §In warm coastal waters, corals make complex reef structures that support ecosystems rivaling the rainforest in diversity.

    “Forests” of multicellular algae (seaweeds and giant kelps) form along many coasts
  24. Littoral Zone
    Area of Coastal zone that is affected by wave action
  25. Intertidal Zone
    •The intertidal lies between high- and low-tide levels; conditions of temperature and salinity vary greatly.

    §Intertidal organisms must withstand being alternately exposed to air or submerged, on a regular basis.
  26. Pelagic Zone
    •In the open ocean, or pelagic zone, the principal consumers are zooplankton—mainly small crustaceans and larval stages of marine animals.
  27. Benthic Zone
    Ocean Bottom

    §Many benthic organisms are adapted to life on the seafloor substrate. They include sessile animals as well as motile bottom feeders such as crabs and sea slugs.
  28. Aphotic Zone
    •Depths reached by less than 1 percent of incoming sunlight constitute the aphotic zone (including the abyssal plain of the deep ocean floor).

    §Organisms in this region subsist on decaying organic matter that sinks down from the photic zone.

    §In deep-ocean trenches and rift valleys, ecosystems are often sustained by chemosynthetic microbes that can metabolize the nutrients in seawater without the aid of sunlight.
  29. Population dynamics
    The patterns and processes of change in a population
  30. Age Structure
    Describes the age distribution of individuals and how those individuals are spread over the environment
  31. Population Density
    Number of individuals per unit of area (volume in aquatics)
  32. Demographic events
    births, deaths, immigration, emmigration

    Affect population structure over time
  33. Demography
    study of population processes
  34. Dispersion patterns
    Clumped- Presence of one individual at one point increases the probability that others will be there

    Regular- Presence of one individual at one point decreases the probability that others will be there

    Random- There is equal probability of any individual occupying any point in space
  35. Life Table
    Keeps track of demographic events: births, deaths, etc
  36. Cohort Life Table
    Keeps track of a group of individuals born at the same time (horizontal life table)
  37. Mortality
    Proportion of each age class that dies before reaching the next age class
  38. Fecundity
    Number of offspring produced by each female
  39. Survivorship curve types
    • Type 1: High survivalship through adulthood (humans)
    • Type 2: Constant risk of mortality at all ages (most birds)
    • Type 3: Low juvenile survivorship (insects)
  40. Life history strategy
    How an organism allocates time and energy amoung various activities throughout its life
  41. Semelparous
    Species that reproduce only once and then die
  42. Iteroparous
    Species that reproduce multiple times in their life
  43. Intrinsic rate of increase
    Highest possible value for r (net reproductive rate)
  44. Environmental Carrying Capacity
    Number of individuals that can be supported by the environment indefinitely
  45. Density dependent factors
    Factors whose effects increase in proportion to population density (food, predation, pathogens, etc)
  46. Density independent factors
    Factors whose effects are not influenced by density of population (Storms, cold seasons, etc)
  47. r-strategists
    life history strategies that allow for high intrinsic rate of increase.
  48. K-strategists
    life history strategies allow themto persist at or near the carrying capacity.
  49. Antagonistic Interactions
    One species benefits and the other is harmed
  50. Mutualism
    Both species benefit
  51. Competition
    two or more species use the same resource
  52. Commensalism
    One species benefits, the other is unaffected
  53. Ammensalism
    One species is unaffected and the other is harmed
  54. Coevolution/Reciprocal Adaptation
    Adaptation in one species leading to evolution in another
  55. Aposematic Coloration
    toxic coloring
  56. Batesian Mimicry
    Colorful appearance in order to seem poisonous, but actually not
  57. Mullerian Mimicry
    A number of aposematic species converge on the same color pattern
  58. Crypsis
    Camouflage, matching the background
  59. Homotypy
    The prey resembles something that the predator considers inedible
  60. Oligophagous
    Specialist feeder: feed on specific range of food
  61. Polyphagous
    feed on vast range of foods
  62. Microparasites
    live and breed within host
  63. Macroparasites
    only briefly attached to host
  64. Frugivores
    animals that eat fruit, essential for seed dispersion
  65. Intraspecific competition
    occurs between members of the same species
  66. Interspecific competition
    Occurs between members of different species
  67. Competitive exclusion
    occurs when a superior competitor blocks another from resources
  68. Resource partitioning
    coexistance of two competing species
  69. Interference competition
    one species blocks another from a resource
  70. Exploitation competition
    one competitor is more efficient in using a resource than another
  71. Guilds
    groups of species that use the same resource in different ways
  72. Character displacement
    difference in species characteristics based on other present competitors
  73. Fundamental Niche
    based on physiological capabilities
  74. Realized Niche
    Based on interspecies interactions
  75. Photosynthetic Primary Production (PP)
    Fixation of solar energy by autotrophs in an ecosystem

    • GPP=total energy produced in ecosystem
    • NPP=energy left over after autotrophs have met energetic needs
    • NPP=GPP-R
  76. Primary consumers
  77. Secondary consumers
    organisms that eat herbivores
  78. Tertiary consumers
    Organisms that eat secondary consumers
  79. Detritivores
  80. Omnivores
    • organisms that fit into more than one trophic level
    • (more common)
  81. Ecological efficiency
    overall transfer of energy from one trophic level to another
  82. Trophic Cascade
    Progression of indirect effects across successive trophic levels
  83. Ecosystem Engineers
    Organisms that affect the ecosystem structure
  84. Keystone species
    species that exerts an influence out of proportion to it's biomass
  85. Alpha diversity
    Species richness within a community
  86. Beta-diversity
    changes in species composition between habitats
  87. Gamma diversity
    Species diversity in a larger region/across several communities
  88. Time hypothesis
    Hypothesis for why species diversity decreases with distance from equator

    Organisms in tropics had more time to diversify under stable climates
  89. Spatial Heterogeneity Hypothesis
    Hypothesis for why species diversity decreases with distance from equator

    Tropics contain more varities of habitats
  90. Specialization hypothesis
    Hypothesis for why species diversity decreases with distance from equator

    Competition in tropics led to more species
  91. Predation hypothesis
    Hypothesis for why species diversity decreases with distance from equator

    Predation is higher in tropics, low prey levels, low interspecific competition, results in ability for rare species to persist
  92. Directional succession
    succession towards a climax community
  93. Flux
    rate at which energy or elements travel through an ecosystem
  94. Sink
    where an element gets taken out of circulation for a while
  95. 4 compartments of physical environment
    Atmosphere, ocean, land, freshwaters
  96. Troposphere
    lowest level of the atmosphere, contains 80% of the mass
  97. Stratosphere
    extends out to about 50km, ozone is here, most air enters near equator from troposphere
  98. Water is most dense at __degrees C
    4 degrees
  99. Thermocline
    in winter, densest water is at surface. In summer it shifts to the bottom. this is a thermocline
  100. Humans consume about __% of the Earth's annual net primary production
  101. Carbon is returned to the environment through
    metabolism by organisms
  102. Oceans absorb more than _____ of CO2 every day, more than any time in the past ______ years
    20-25 million tons, 20 million
  103. Keeling Curve
    Curve used to demonstrate increase in CO2 levels due to burning of fossil fuels
  104. Mean residence of nitrogen in the biosphere is
    625 years
  105. Eutrophication
    where water bodies recieve excess nutrients from fertilizers
  106. Residence of phosphorus in biosphere
    1000 years
  107. Conservation Biology 3 principles
    • Evolution unites biology
    • Ecological world is dynamic
    • Humans are part of the ecosystem
  108. __% loss in habitat results in a __% loss in species