The Transport of Oxygen and Carbon Dioxide by Some Bloods Containing Hemocyanin. by Alfred

Since the classic observations of Bert (1867) and Fredericq (1878) called attention to the significance of the copper-protein compound, hemocyanin, subsequent investigators have concerned themselves with two questions of biological importance.’ What is the general nature of the union whereby hemocyanin may function as an oxygen carrier in the blood? Do the hemocyanins of various groups of animals exhibit specific differences? The answer to these questions will give basic facts on which an understanding of the physiology of respiration must be built, and on which comparative physiology can draw for contributions to our doctrines regarding the evolution of organisms and their relation to the environment. The present paper describes an examination of the general conditions of equilibrium between oxygen, carbon dioxide, and the blood of four species of invertebrates. It appears from this and other contemporary work that the hemocyanins, together with the hemoglobins, form a considerable group of proteins which function in the transport of oxygen and carbon dioxide in a manner which is the same in principle though distinctive in its quantitative details in different animals.