Another interesting fact about an octopus is that its blood is blue in colour. We have red blood because it contains an iron-based protein called hemoglobin. But the octopus has a copper-based protein in its body called hemocyanin, due to which the blood turns blue. Hemocyanin does not blend with oxygen as easily as hemoglobin does. Because of this, two hearts pump blood through the gills, which get oxygen and blood, and the third heart pumps it throughout the body.
#octopuses Are A Species Of Many : Eight Legs, Nine Brains, Three Hearts And Blue Blood. #unbelievable ! Meet the animal with three hearts and nine brains #information