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Labs:
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Notes:
   Animal Body
   Arthropods
   Biochem
   Cell Cycle
   Cell Interactions
   Cell Structure
   Circulation Respiration
   Communities
   Digestion
   DNA
   Ecosystems
   Energy
   Evolution Evidence
   Future of Biosphere
   Genetic Engineering
   Gene Function
   Genetics
   Hormones
   Human Evolution
   Immunity
   Species Interaction
   Kidneys
   Locomotion
   Membranes
   Mollusks
   Mutation
   Nervous
   Non-Coelmic
   Photosynthesis
   Plant Physiology
   Population Genetics
   Population Dynamics
   Cellular Respiration
   Sensory
   Speciation
   Taxonomy
   Vertebrates
   Vertebrate Org
Vocabulary:
   1,2,3,4,5,6,7,8,9,10,
   11,12,13,14,15,
   16,17,18,19,20,
   21,22,23,24,25,
   26,27,28,29,30,
   31,32,33,34,35,
   36,37,38,39,40,
   41,42,43,44,45,
   46,47,48,49,50,
   51,52,53,54

Photosynthesis

    Evolution -
      3 billion years ago ~> Green Sulfer Bacteria (H2S) Photons absorbed by P700 (Photosystem I) to Ferredoxin Ejects e- (Accompanied by H+ from H2S) e- channeled through cytochromes This passage chemiosmatically produces ATP
    Cyclic Photophosphorylation -
      First version of Ps Not a true cycle
    Limitations -
      Geared towards E production (no biosyntheis; Dark rxn         s) Scavenge for alternative source of hydrogen
    Today -
      *Modern autotrophs have developed a photosystem II (P680) *This has allowed for the use of H2O as the H+ source.
    General Information
      Series of redox rxns Production of food by the plant thru conversion of light evergy into chemical energy Capture of 1% of light energy to power all life H2O is the source of O2 released by Ps Proven with use of 18O isotope
2 STEP PROCESS
    Light Dependent -
      Occurs in the thylakoid membranes Depends upon light intensity Harvest light to produce ATP & NADPH
    Light Independent -
      Occurs in the stroma Depends upon temperature Combine products from light rxns with CO2 to synthesis nutrients
    Light -
      Consists of energy called photons Measured in packets of energy called quanta Energy of photons is directly inverse to its wavelength Photoelectric effect ~> light excites electrons in a metal causing it to eject an electron
      Photons are either captured or lost as heat Absorption Spectrum - range of photons capable of being absorbed Pigment - colored molecule efficient at absorbing light
        Types:
          Carotenoids -
            Carbon rings attached to side chains w/ alternating single & double bonds High range of absorption Ex. Beta-Carotene - (split into Vitamin A & oxidized to retina         l)
          Chlorophylls -
            porphyrin rings - alternating single and double bonds w/ Mg atom at the center Excited electron from Mg leaves the molecule thru the carbon bond system Side chains alter absorption properties Methanol <CH3> chlorophyll a ~> violet-blue; reflects 500-600nm(Gree         n) Aldehyde <CHO> chlorophyll b ~> reds; reflects 500-600nm(Gree         n)
          Xathophylls -
            In plants Yellow-orange

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