BIO 381 final

  1. some parts of the endocrine system?
    thyroid, pituitary gland, pancreas, ovary, testes
  2. EDCs
    endocrine disrupting compounds
  3. Two different classifications of EDCs?
    those that occur naturally, and those that occur synthetically
  4. EDCs exert their effects by...
    • 1. mimicking or antagonizing the effects of hormones
    • 2. altering the pattern of synthesis + metabolism of hormones
    • 3. modifying hormone receptor levels
  5. Endocrine disruption?
    EDCs indirectly interact with the endocrine systems that control bodily functions, resulting in excessive amounts or suppression of hormones
  6. Number of chemicals/heavy metals that are reported of having endocrine disrupting actions?
    ~38 000
  7. Number of chemicals that according to the ESEPA need to be tested to see if they effect the endocrine system?
    87 000
  8. 3 kinds of potential endocrine disrupting pharmaceuticals?
    • steroidal pharmaceutical substances
    • personal care products
    • nonsteroidal pharmaceutical substances
  9. Atrazine
    herbicide, also a potent endocrine disrupter that's active at low ecologically relevent concentrations
  10. BPA
    bisphenol A, the substance that leaked out of the rat cages in that lab, caused abmormalities in chromosomes/meiosis
  11. Pollutants ______ song complexity and the _____ of the brain area HVC in a songbird
    increase, volume
  12. Lake that suffered a major spill of which pesticides in 1980?
    • Lake Apopka (Florida), dicofol and DDT
    • - had affects on alligators
  13. tributylin (TBT)
    • component of anti-fouling paints 
    • - causes "imposex" in a range of male gastropods
    • - endocrine disruption believed to involve suppression of enzyme aromatase (converts androgens to estrogens)
  14. imposex
    conditions in which male sex organs (penis and vans deferens) are superimposed in a female gastropod, effectively preventing the animal from reproducing
  15. Feminization
    • domestic and industrial effluents may cause feminization in fish
    • - incl. high levels of vitellogenin in blood of male fish
    • - occurance of oocytes in testes of presumed male fish
  16. Vitellogenin
    a protein synthesized in blood of male fish under estrogenic stimulation and secreted into the blood stream for incorporation, as the precursor for some of the yolk proteins, into developing oocytes
  17. Seems that the most pervasive estrogens in the aquatic environment are _________________
    steroids derived from human excretion
  18. Intersex
    condition where an individual is intermediate in sexual characteristics b/w a normal male and a normal female
  19. Intersex fish: chronic exposure of fish to very low concentrations of the __________________ stimulated vitellogenesis, also sex reversals in males to phenotypic females
    synthetic steroid ethinyl estradiol (1.5ng/L)
  20. exposure to low concentrations of the androgenic steroid __________ has a masculinizing effect _____________
    methyltestosterone, (suppression of vitellogenesis, sex reversal of female to males)
  21. 17a-ethinylestradiol (EE2)
    • used in birth control pills
    • found downstream of sewage treatment plants
    • more persistent than other estrogens 
    • induces vitellogenin production in male fish at low ng/L
    • acutely toxic to aquatic organisms at mg/L
  22. Symptoms of male and female fish from ELA when EE2 added to lake?
    • Males: display intersex, primary-stage oocytes among remnants of testicular tissue
    • Females: ovaries had atretic follicles
  23. Minamata Disease?
    • Chisso Corporation Factory in Minamata, Japan 
    • opened in 1932 
    • pumped 500 tons of effluent per hour into Minamata Bay
    • people ate the fish out of the bay, got mercury poisoning aka "Minamata Disease"
  24. two biggest industries that contribute to atmospheric mercury?
    coal burning, gold mining (in poor regions mercury still used for gold panning, gold sticks to the mercury)
  25. Three basic forms of mercury:
    • 1. Hg(0) 
    • 2. Hg(II)
    • 3. MeHg
  26. Hg(0)
    • Elemental mercury, most prominent in atmosphere
    • reduced form, quite volatile (can be gaseous)
  27. Hg(II)
    • Ionic mercury, oxidized
    • comes out of atmosphere in rain
    • primarily found in plants, soils, lakes
  28. MeHg
    Methylmercury, bioaccumulates and biomagnifies
  29. 2 basic mercury processes of importance
    • 1. microbial methylation of Hg(II) to methylmercury
    • - done primarily by sulphate-reducing bacteria in anaerobic environments like lake sediments or saturated wetland peat
    • 2. photoreduction of Hg(II) or methylmercury into Hg(0)
    • - sort of a good process, done primarily by UV radiation
  30. Marketing limits for Hg consumption advisories
    Canada: 0.5ppm Hg (or 0.5 micrograms Hg per g food)
  31. Recommended daily intake level of Hg for pregnant women or children under 12?
    0.2 micrograms per kg of bodyweight
  32. consumption of __________ is the primary route of methylmercury exposure in humans
    contaminated fish
    Mercury Experiment to Assess Atmospheric Loading in Canada and the US
  34. spike mercury
    all the mercury experimentally loaded onto the watershed, including the isotope and its impurities
  35. ambient mercury
    all mercury that is not spike mercury
  36. Half-life (in days) of mercury on forest canopy vegetation
    • Conifer: 183 days
    • Deciduous: 108 days (shorter bc leaves break down more readily)
  37. demethylation
    destruction of methylmercury
  38. Climate phenomenons that have a low confidence that there is a human contribution to observed changes?
    Intensity and/or duration of drought, increase of tropical cyclone activity
  39. General trend of changes in annual precipitation over land
    wet areas getting wetter, dry areas getting drier
  40. Trends: Northern hemisphere spring snow cover..
  41. Trends: arctic summer sea ice extent..
  42. Trends: change in global average upper ocean heat content..
  43. Trends: global average sea level change..
    rising, due to thermoexpansion of water and melting glaciers/icecaps
  44. Trends: surface ocean CO2 and pH..
    • CO2 rising, pH lowering
    • - as atmospheric CO2 increases, it diffuses into the ocean and ocean CO2 levels rise, then the ocean becomes more acidic
  45. Radiative forcing (RF)
    • measurement of the capacity of a gas or other forcing agents to affect that energy balance, thereby contributing to climate change 
    • - shows how different chemicals/things we know affect climate change are changing the radiative forcing of the earth
  46. Main radiative forcing agents:
    • Well-mixed greenhouse gases
    • - CO2
    • - CH4 
    • - halocarbons
    • -N2O
  47. Aerosols and precursors
    • mineral dust, sulphate, nitrate, organic carbon, black carbon
    • do negative radiative forcing
  48. Three large-scale indicators of climate change in the atmosphere, cryosphere, and ocean
    • 1. change in continental land surface air temps
    • 2. Arctic and Antarctic September sea ice extent
    • 3. Upper Ocean heat content in the major ocean basins
  49. in the IPCC report, difference between RCP2.6 and RCP8.5
    RCP2.6 means human activity levels if we "get our act together", RCP8.5 represents if we continue with business as usual
  50. Climate change drivers
    • natural fluctuations in solar output (SWR)
    • aerosols (SWR)
    • clouds (SWR, LWR)
    • ozone (SWR, LWR)
    • greenhouse gases and large aerosols (LWR)
    • surface albedo changes (SWR)
  51. a light surface albedo of ice and snow will _________
    reflect light away
  52. surfaces with a dark albedo like the ocean will ___________
    absorb heat and light
  53. _________, the active weather layer of the atmosphere, is _________
    troposphere, warming
  54. more than ____ of the excess energy absorbed by the climate system has been stored in the _______
    90%, oceans
  55. Main contributors to rising sea levels
    • thermoexpansion of water
    • melting glaciers and icesheets
    • changes in storage and usage of water on land
  56. salt water has a _______ heat capacity than fresh water
    lower, so the higher the salinity of the water, the faster it will warm
  57. atmosphere can hold ____ more water vapour for each _________ of warming
    • 7%, degree celcius
    • therefore the warmer the air, the moister
  58. Increased CO2 levels in the ocean means:
    • acidified ocean
    • shifts the bicarbonate cycle
    • decreases pH over time
  59. Bicarbonate cycle
    when atmospheric CO2 exchanges across the air-sea interface, it reacts w/ seawater through a series of 4 chemical reactions that increase the concentrations of the carbon species: dissolved carbon dioxide, carbonic acid (H2CO3), and bicarbonate (HCO3-)
  60. The 4 reactions in the bicarbonate cycle:
    • CO<-> CO2
    • CO2 + H2O <-> H2CO3
    • H2CO3 <-> H+ + HCO3-
    • HCO3- <-> H+ + CO3
  61. Time series of changes in large-scale ocean climate properties? (4)
    • - carbon (increasing)
    • - global mean sea level (increasing)
    • - upper ocean heat content (increasing)
    • - high salinity minus low salinity (increasing)
  62. in the past _____, ________ trend of average annual extent of sea ice in the arctic  of ________
    34 years, downward, 3.8% per decade
  63. ______ shows ____ of _____ per decade of average annual extent of sea ice
    Antarctic, decrease, 1.5%
  64. Equilibrium line altitude (ELA)
    • for a given climate, the ELA has a specific altitude (ELA1), due to temperature increases ELA shifts to a new altitude (ELA2)
    • after the glaciers readjust to the new ELA, some glaciers have shrunk and some have completely disappeared
  65. Changes in the cryosphere: frozen ground
    increasing permafrost temps up to 2°C, increase in active layer thickness
  66. changes in the cryosphere: snow cover
    decreases throughout the year, largest decreases (53%) in June
  67. changes in the cryosphere: lake and river ice
    • contracting winter ice duration, delays in autumn freezeup
    • - evidence of recent acceleration of both across the NH
  68. changes in the cryosphere: glaciers
    melting to glaciers major contributer to sea level rising
  69. changes in the cryosphere: sea ice
    • arctic sea ice extent declines at rate of 3.8% per decade
    • extent of thick multiyear ice in arctic declined at rate of 13.5%/decade
  70. changes in the cryosphere: ice shelves and ice tongues
    continuing collapse and retreat of ice shelves along Antarctic peninsula
  71. changes in the cryosphere: ice sheets
    Greenland and Antarctic ice sheets lost mass and contributed to sea level change over the last 20 yrs
  72. main natural processes that remove CO2 from the atmosphere:
    • Land uptake (photosynthesis- respiration)
    • ocean invasion: seawater buffer
    • reaction w/ calcium carbonate
    • silicate weathering
  73. lots of nitrogen produced through the making of ________
    fertilizer (Haber Bosch process)
  74. What happens to CO2 after its emitted into the atmosphere?
    • rapidly distributed b/w atmosphere, upper ocean, and vegetation
    • carbon continues to be moved b/w the different reserviors of the global carbon cycle (soils, deeper ocean, rocks)
    • depending on how much CO2 is released, bw 15% and 40% will remain in the atmosphere for up to 2000yrs
  75. Scattering aerosols:
  76. Absorbing aerosols:
  77. _____ can act as _______ upon which liquid droplets form
    aerosols, cloud-condensing nuclei
  78. Contribution of water vapour to the greenhouse effect relative to that of CO2 considered to be __________
    2 to 3 times greater
  79. Black carbon
    from fossil fuels and biofuels, if you deposit it on snow packs it changes the albedo really quickly so there's more melting going on compared to if there were no emissions of black carbon
  80. Big 3 RF'ers
    CO2, CH4, halocarbons
Card Set
BIO 381 final