Question

what is the difference in haemoglobin in animals and humans

Answer 1

Most non-mammalian animals have nuclei in their mature erythrocytes, or red blood, cells, but mammals, including humans, do not. Comparing mammals, the main difference between the blood of two different species is the same as the difference between two people; the proteins that allow for self-identification. Haemoglobin, an iron-containing protein found in the blood of other animals—including humans—serves the same oxygen-transporting function but turns blood red. Both haemoglobin and hemocyanin release their bound oxygen when they reach tissues that need it