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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

Membranes

    Made of bilayer systemMade of phosopholipids (phospholipid bilayer)Glycerol (backbone), 2 Fatty Acids & Alcholphoshate group


    Proteins present in membraneSemi-permeable; selectivily permiableFluid mosaic modelMembranes are fluidSpinSwitch placesFlip flopMore unsaturated ~> more fluidColder ~> less fluidProteins-
      Can more, but cannot move out of membrane
    Stabilizing Factors
      Hydrophobic interactions that keep bilayer intactH-bonding w/ phosphateCholesterol ~> seperate phospholipids
    Destabilizing Factors
      Double bonds in fatty acids ~> more fluid, but less stableRotation & flipping of phospholipid
        Increase fluidity
    Transmembrane Proteins
      Enzymes - Membrane bound
        Increase efficiency of metabolic rxns.
      Receptor - Transmit information from outside the cell to the inside
        Hormones - specific site & will change conformation of protein inside the cellProstaglandin - (pain response)
          Anti-inflammatory agentsEffects of aspirin
        Anti-bodies
      Channel Proteins - passive transport across the membrane (ex. Na+/K+ pump)Carrier Proteins - active transport across the membrane (ex. Sugar Transport)
        facilative diffusion
    Cell Surface Markers
      Glycocalyx - layer on outside composed of sugarsGlycoprotein - "self recognition" - recognizes individuals (ex. Major Histocompatability Complex (MHC))Glycolipid - Tissue recognition (ex. A,B,O Blood Groups)
    Interior Protein Network
      Spectrin - determines shape of cell; provides an internal structureClatharin - Anchor proteins especially during receptor mediated endocytosis
    5 ways they Regulate Movement
      OsmosisDiffusion (passive transport)Bulk passive - phagocytosisReceiving InformationPhysical connection between cells
    Movement of Materials Across Membrane
      Large polar molecules which are uncharged & ions cannot pass freely (Glucose, Cl-, Na+, K+, C++, proteins)Small-uncharged polar molecules and hydrophobic molecules can pass freely (ex. H2O, CO2, O2, hydrocarbons)Two Types of Movement:

        Diffusion -

          Movement of materials from high to low [ ]Low random motion dependent on concentration gradientSmall Uncharged molecules free to pass through membrane
        Facilitated Diffusion -
          Movement from high to low [ ]Moderate to large size moleculesRequire channel proteins to help them inDepend on [ ] gradient & channel availability
        Osmosis -
          Hydrostatic Pressure -
            Pressure exerted by cytoplasm pushing on membrane
          Osmotic Pressure -
            Increase in hydrostatic pressure due to movement of H2O into cell*Used to stop Osmosis*
          Turger Pressure -
            Created by pressure of fluid against cell wall*Wilting*Central Vacuole
          Plasmolysis -
            Shrinking of membrane due to H2O loss
          Osmotic potential is based upon [ ] of solutes

    Maintence of Osmotic Balance

          Fresh Water Protists -
            Adaption: Contractile Vacuole
              Store & Expel H2ORequires energy (active process)Maintain homeostasis
          Plant Cells -
            Cell wallsTurger pressureCentral vacuole
          Human Body Cells -
            Usually isotonic w/ extra cellular fluidsUse ion pumps; selective permeability
            Special proteins ~>serum albumin

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