Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Colour of Blood

  1. Jan 13, 2004 #1
    What determines the Colour of BLOOD And why the colour of insects different?

    I dont know Biology But i want the answer for above just to add to my knowledge
  2. jcsd
  3. Jan 13, 2004 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Haemaglobin is the cause of red blood in vertebrates, as are its derivatives haematin and haematoporphyrin. Insects have a different molecule: hemolymph.

    An interesting little fact about insects:
  4. Jan 13, 2004 #3
    Wow monique, thanks for that, it really is true that you learn something knew everyday. Never normally that interesting though.
  5. Jan 14, 2004 #4

    Another God

    User Avatar
    Staff Emeritus
    Gold Member

    Is it the Haemoglobin Molecule that is red, or is it the Iron associated with it that makes it red...?

    Same question with the Insect blood... Is it the molecule itself, or another contributing factor?
  6. Jan 14, 2004 #5
    http://www.bio.ph.ic.ac.uk/molbio/mols/hb/hb.fr.html [Broken]

    I believe it is not due to Iron alone
    Last edited by a moderator: May 1, 2017
  7. Jan 14, 2004 #6
    The color of an ion depends on its environment. In aqueous solution ferric irons (Fe3+) are coordinated with six water molecules and have a yellow color rather than the reddish color in case when coordinated with six oxide ions, while the anhydrous chloride is greenish. Fe2+ are green in aqueous solution but that doesn't say much, the presence of nitrogen and oxygen (only oxyhemoglobin is bright red) are going to affect the color significantly. The iron is definitely what is responsible, though, and most brightly colored compounds are made so by coordinated transition metals. And probably due to environment of iron Coordination Complex
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook