Red color gives a blood hemoglobin - the pigment that carries kislorod.No many invertebrates used to carry oxygen hemoglobin and other pigments, "working part" of which the ions of different metals. In particular, the blood of many molluscs, arthropods and other animals comprising hemocyanin - pigment with the copper ion. Most often, this compound makes the blood blue, and sometimes bluish green. Green blood and has one of the frog species found in Cambodia. This is due to the pigment biliverdin. It is produced in the liver, including humans, as an intermediate breakdown product of hemoglobin and that it gives green bile. However, the frog, unlike us, it is not excreted in the bile through the intestines, and fed back into the blood. Sometimes green blood in humans. It happens very rarely when blood overabundance of sulfur compounds, for example, as a result of the abuse of medicines containing this element. Sulfur easily binds to hemoglobin. The resulting compound sulfogemoglobin gives blood dark green as the avocado peel color. As a rule, themselves owners of green blood is not worried.
via factroom.ru