Bio energy flow and photosynthesis

  1. metabolic pathway
    series of enzyme-mediated reactions by which cells build, remodel, or break down an organic molecule
  2. draw a representation of linear and cyclic metabolic pathways
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  3. how are metabolic pathways controlled
    • concentrations of reactants and products
    • feedback inhibition
    • allosteric sites
    • this control over the enzymes allows cells to conserve energy and resources by producing only what they require
  4. feedback inhibition
    • mechanism by which a change that results from some activity decreases or stops the activity
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  5. allosteric site
    • a region of an enzyme, other than the active site, that can bind regulatory molecules
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  6. vitamin
    organic molecules required in small amounts for normal growth, reproduction and tissue maintenance
  7. mineral
    inorganic chemical element required by organisms for normal growth, reproduction and tissue maintenance
  8. insulin
    hormone secreted by the pancreas that regulates blood sugar
  9. type 1 diabetes
    lack of insulin production
  10. type 2 diabetes
    receptors on cells respond poorly to insulin
  11. how can the release of sugar be helped with diet
    fiber eaten with digestible carbs can help slow the release of sugar, reducing the risk of surges in blood sugar
  12. energy
    the capacity to do work
  13. conservation of energy
    energy cannot be created or destroyed but converted from one form to another
  14. forms of energy
    • chemical energy
    • potential energy
    • kinetic energy
    • heat
  15. chemical energy
    • the potential energy stored in the bonds of biological molecules
    • breaking these bonds releases that stored energy, making it available to power cellular functions
  16. potential energy
    stored energy
  17. kinetic energy
    the energy of motion or movement
  18. heat
    the kinetic energy generated by random movements of molecules or atoms
  19. efficiency of energy transformation
    • not efficient
    • energy is lost to the environment as heat
    • reason for need of energy input (food for example)
  20. autotroph
    organism that captures the energy of sunlight by photosynthesis (plants, algae, cyanobacteria)
  21. heterotroph
    organism that obtains energy by eating organic molecules that were made by other organisms (humans, animals)
  22. photosynthesis
    the process by which plants and other autotrophs use the energy of sunlight to make energy-rich molecules using carbon dioxide and water
  23. process of photosynthesis
    • sunlight + water + carbon dioxide > oxygen + glucose
    • carbon dioxide is the carbon source
    • glucose is produced
    • splitting of water molecules result in oxygen as a by-product
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  24. 2 parts of photosynthesis
    • photo part - light energy is captured in chemical form. during the process water is split releasing oxygen as a by-product
    • synthesis part - chemical energy is used to generate glucose molecules using the carbon atoms of carbon dioxide
  25. chloroplasts
    organelle in plant and algae cells where photosynthesis occurs
  26. light energy
    the energy of the electromagnetic spectrum of radiation
  27. photons
    • packets of light energy, each with a specific wavelength and quantity of energy
    • the human eye perceives each wavelength as a different color
  28. chlorophyll
    • the pigment present in the green parts of plants that absorbs photons of light energy during the light reactions of photosynthesis
    • it absorbs the red and blue wavelengths of visible light and reflects green (this is why leaves appear green)
  29. how does photosynthesis work
    • when red and blue photons are absorbed by chlorophyll during the light reactions, the electrons in its atoms become excited.
    • these excited electrons are used to generate energy in the form of ATP (adenosine triphosphate) which is used in the synthesis part of photosynthesis to make sugar
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  30. carbon fixation
    • the conversion of inorganic carbon (ie CO2) into organic forms (ie sugars)
    • carbon fixation is ultimately the way carbon enters the global energy chain
    • resulting sugars can be eaten by animals and humans or used by plants to grow and increase their biomass
  31. benefits of algae
    • very efficient energy converters - the oil they produce is rich in chemical energy
    • all they need to make the oil is sunlight, carbon dioxide, water, nitrogen and phosphorus
    • they can be modified using biotechnology
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Card Set
Bio energy flow and photosynthesis
bio 160 ch 5