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Homework Help: Lab on Photosynthetic Pigments/Absorbance

  1. Jun 24, 2010 #1
    1. The problem statement, all variables and given/known data

    Hi guys. So i have to write a lab report on a lab we did on photosynthetic pigments. Just to give you some background, we extracted pigments from spinach leaves by first boiling them in water and then putting them in ethyl alcohol.

    Then we used chromatogrpahy paper to separate the different pigments.

    Later, we used a spectrophotometer to take the absorbance spectra of chlorphyll pigments.

    My question is:
    in our lab report they are very nitpicky about making sure we write about the "broader implications" of our conclusions.

    I cannot for the life of me figure out what the broader implications are for the fact that different pigments have different solubilities (and therefore can separate by chromatography)

    I also cannot figure what the broader implications are for the absorbance spectra of chlorophyll. I guess that this is why leaves are green? or that these results might be able to help in understanding the importance of maintaining the ozone or something? i'm just making guesses.

    Any ideas or things to think about would be helpful, thank you.

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Jun 24, 2010 #2


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    2017 Award

    Being able to separate molecules from other similar molecules is one of the most important skills in chemistry. Once you can isolate a specific molecule, you can now study it without having to worry about your results being affected by other contaminating molecules.
  4. Jun 24, 2010 #3
    Leaves are green because they do not absorb light of wavelengths that we percieve as green. I suppose identifying the wavelengths across which chlorophyll molecules can absorb will give some indication of the efficiency with which plants can take in energy from the Sun. Remember that producers are a necessary stage in all ecosystems, and that they transform the energy from the Sun in to one which can be used by primary, secondary, ..., consumers. The efficiency with which they do this has implications for ecosystems (such as they number of trophic levels, diversity, stability) and, I suppose therefore, life on earth.
    Just a thought...
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