questionedithistorytranslationsCurrent version This is the accepted version. added by Kasia Aug. 16, 2012, 8:15 a.m. What color is octopus blood? redbluegreenyellowBoth squids and octopuses have blue blood. They use an oxygen-carrying molecule in their blood called hemocyanin that contains copper. In cold conditions with low oxygen pressure, hemocyanin oxygen transportation is more efficient than haemoglobin oxygen transportation.KasiaShare and bring new players to the game!0Very uninterestingToo difficultPoorly writtenIncorrect or questionableCorrect this question7Very interesting!reach: rather globalanimalsbloodchemistrycolorsnatureoctopusessea animalszoologyVotes +7 Very interesting! globalquiz.org