In 1879 C. Nageli formulated his well-known molecularphysical theory, which supported Liebig's chemical theory on the one hand and Pasteur's physiological hypothesis on the other: "Fermentation is the transference of the condition of motion of the molecules, atomic groups and atoms of the various compounds constituting the living plasma, to the fermenting material, in consequence of which equilibrium in the molecules of the latter is destroyed, the result being their disintegration."
In this respect the plasma behaves in a similar manner towards the sugars as does the living yeast cell.
The plasma is coloured red by haemoglobin: it is sometimes (in Sabella and a few other Polychaeta) green, which tint is due to another respiratory pigment.
The plasma may be pink (Magelona) or yellow (Aphrodite) in which cases the colour is owing to another pigment.
In one genus (Planorbis) the plasma of the blood is coloured red by haemoglobin, this being the only instance of the presence of this body in the blood of Glossophorous Mollusca, though it occurs in corpuscles in the blood of the bivalves Arca and Solen (Lankester).
Kidneys, pancreas and the thyroid gland, also in muscle-plasma; " crystalline," a globulin occurring in two forms a and /3, is found in the lens of the eye; " egg-globulin " and " lactoglobulin " occur respectively in the white of egg and in milk.
Fibrinogen occurs in the blood plasma, and is changed by a ferment into fibrin, to which the clotting of blood is due.
The blood-corpuscles are large amoebiform cells, and the blood-plasma is coloured blue by haemocyanin.
A " transudate " is a liquid having a composition resembling that of blood-serum, while the term " exudate " is applied to an effused liquid whose composition approaches that of the blood-plasma in the relationship of its solid and liquid parts, besides in most cases containing numbers of colourless blood-corpuscles.
Thus Ludwig was of opinion that the lymph-flow is dependent upon two factors, first, difference in pressure of the blood in the capillaries and the liquid in the plasma spaces outside; and, secondly, chemical interchanges setting up osmotic currents through the vessel-walls.
393; Justi, " Unna's Plasma-Cells in Granulations," Arch.
162; Krompecher, " Plasma-Cells," Beitr.
BLOODSTONE, the popular name of the mineral heliotrope, which is a variety of dark green chalcedony or plasma, with bright red spots, splashes and streaks.
They are slowly absorbed into the blood, and are a natural constituent of the blood plasma, which derives them from the food.
The Trypanosomes, in the active phase, are of course always free in the blood plasma (interglobular).
Quinine administered by the mouth or by any other means will soon enter the blood, and will then kill the haematozoon malariae, whether it be free in the blood-plasma, in the leucocytes or in the red blood corpuscles.