Is there any difference in the blood between humans and animals?
R. THIRUMALAI
Madanapalle, Andhra Pradesh
Human and other animal blood is different in many aspects. Human blood is always warm blooded whereas cold blooded in other animals except in mammals and birds.
The percentage of the cell types in human and other animals are different between each other. In humans blood vascular system is closed , whereas some animals have open blood vascular system.
The efficiency of human blood function is very high than other animals. In active, larger animals with high metabolic activities they have developed metal containing respiratory pigments in their blood. Haemoglobin is found in all vertebrates except a few fishes. Among the invertebrates it is found in many annelids, in a few molluscs and arthropods, in several sea cucumbers, in flatworms, nematodes etc.
In vertebrates, the haemoglobin is contained in the red blood cells whereas in invertebrates it is dissolved in blood plasma. Chlorocruorin , another respiratoy pigment is green in colour found in the plasma of certain tube dwelling polycheate worms.
Haemocyanin is a copper containing pigment found in several invertebrates such as molluscs and arthropods. Human blood is composed of three cell types namely RBC, WBC and platelets. In humans the RBC is enucleated whereas RBC of birds and many animals are nucleated. Both RBC's and haemoglobin are absent in crocodiles. Different blood types based on presence or absence of blood groups such as A, B, O, and Rhesus factor ( Rh) are present in mammals but not in lower animals.
DR. SAINUDEEN PATTAZHY
Associate Professor in Zoology
S.N. College, Kollam , Kerala
