The liquid part (or fluid parts) of blood is called plasma. Plasma is a colourless liquid which is present mainly in multicellular bodys which consists mainly of water with many substances dissolved in it. Plasma contains about 90 percent water. Plasma also contains dissolved substances such as proteins, digested food (energy), common salt (like sodium chloride), waste products (like carbon dioxide and urea), and hormones (like thrombopoietin). Plasma carries all these dissolved substances from one part to another part in the multicellular body like mammals, whereas in other animals (e.g. birds, amphibians . Red blood cells, white blood cells and platelets are immersed in these liquid called plasma.