Disclosed is a centrifugable syringe and syringe components for use in blood fractionation. Also disclosed is a method of blood fractionation using the syringe. The syringe comprises a substantially transparent barrel, a substantially transparent, elongated delineation neck, a plunger for drawing blood into and expelling blood from the barrel, and an adapter attached to the neck for enabling releasable connection of a selected device over an inlet/outlet opening in the neck. The delineation neck extends away from a distal end of the barrel. The barrel and the neck have respective axial bores in fluid flow communication with each other, the cross sectional area of the bore in the delineation neck being substantially less than the cross sectional area of the bore in the barrel. The selected device may be one of various devices including a capping device sealing the inlet/outlet opening of the neck, a needle device used during withdrawal of blood from a subject through the neck, or a hose device used to carry away delineated blood fractions from the syringe through the neck.