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Blood Color

  1. Feb 2, 2006 #1
    What wouldit mean if your blood is dark?
  2. jcsd
  3. Feb 2, 2006 #2


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    It means you are a dark soul, and spawn of the devil.

    What do you mean dark? It probably means more of the iron in your hemoglobin has bonded with oxygen.
  4. Feb 3, 2006 #3
    Whenver I have my blood drawn it seems I have dark blood.
  5. Feb 3, 2006 #4


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    What do you mean "dark" ? Venous blood is darker (more crimson) than arterial blood (more cherry red).
  6. Feb 3, 2006 #5
    The red to dark red color of the blood is due to the large numbers of circulating red blood cells, the erythrocytes. Erythrocytes are called red blood cells because they have hemoglobin, an iron containing pigment. The color of plasma is yellow due to presence of bilirubin, a degradation product of RBC and carotene. Darker color plasma is seen in animals such as horses, cattle, and rabbits, which have high levels of carotene in their blood . Plasma can also be darker in color in animals with bilirubinemia (high bilirubin in the blood). The level of bilirubin in the blood is a useful diagnostic tool for kidney and liver diseases.

    and as Curious3141 said,
    In humans and other hemoglobin-using creatures, oxygenated blood is a bright red in color. Deoxygenated blood is a darker shade of red, which can be seen during blood donation and when venous blood samples are taken.
    Last edited: Feb 3, 2006
  7. Feb 3, 2006 #6


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    It means that what you're seeing in the movies is really carob syrup - bright red - which looks nothing like real blood. :biggrin:

    As fargoth says: "...oxygenated blood is a bright red in color. Deoxygenated blood is a darker shade of red..."
  8. Feb 4, 2006 #7


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    Why are some of the vanes up by my skin blueish and greenish, and varicose vanes are purpleish?
  9. Feb 2, 2010 #8
    Read this, it will explain everything. http://scienceblogs.com/scientificactivist/2008/04/why_are_veins_blue.php" [Broken]
    Last edited by a moderator: May 4, 2017
  10. Feb 2, 2010 #9


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    I think he might have moved on by now...:wink:

    But, since this thread has been brought back to life...

    The other day while out for a late night walk, I witnessed an act of vandalism where an angry, drunk yoot put his fist though a half inch plate office window - twice. While giving my statement to the cops, I realized I was surrounded by this guy's blood spattered all over the sidewalk.

    I was quite astonished to see that, even at night under a streetlight, the blood was bright red, like ketchup. It looked so much like ketchup in fact, that, if I had not witnessed the crime, and had simply come across the scene out-of-context, I would have assumed it was ketchup, and not even questioned it.

    Clearly, this guy gashed an artery, rather than a vein, but I had thought the blood would have been more crimson.

    (P.S. Because of my call, the guy was picked up a half block away (clutching his hand in a blood-drenched rag), treated by paramedics and charged.)
    Last edited by a moderator: May 4, 2017
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