An electron microscope and autoradiographic study of the calciferous glands of the earthworm,Lumbricus terrestris

Abstract

The actively-secreting cells of the cMeiferous glands of Lumbricus terrestris are roughly dome shaped. The basal part of the cell consists of numerous interdigitating cell processes. These processes contain numerous mitochondria and membranous infoldings, forming vesicles which migrate to various regions of the cell. The nucleus is irregular and centrally located. The supranuclear region is occupied to a great extent by the rough endoplasmic reticulum, several Golgi complexes and numerous granules derived from the Golgi complexes. These granules enlarge and are extruded into the gland sinus, where they eventually become reorganized and mineralized to give rise to spheroliths.Radioautographs of glands removed 30 rain following injection of 45Ca showed uptake of the isotope located almost exclusively in the cells; 4--24 h later the isotope was located in the spheroliths in the gland cavity.These cells apparently perform two functions necessary for the production of mineralized spheroliths, l, absorption and transport of calcium from the basal region to the cell surface and 2, the elaboration of a protein matrix in which mineralization occurs.

Origin of Calcium carbonate granules found in buried soils and Quaternary deposits

“…The above description is broadly supported by many other published studies addressing various aspects of earthworm physiology and the details of their calciferous glands (Perrier 1874;Beddard 1894;de Ribaucourt 1901;Smith 1924;Stephenson 1930;Bevelander & Nakahara 1959;Laverack 1963;Crang et al 1968;Nakahara & Bevelander 1969;Morgan 1981;Jamieson 198 1 ; Schrader 199 1).…”

Analysis of secondary carbonates from the young loess-paleosol sequences of the Carpathian Basin - especially regarding their paleoenvironmental role

“…The function of the calciferous gland DARWIN, C. (1882) already recognized, that when calciferous glands of earthworms are squeezed, pulpy white matter flows out with fine granular matter inside. As a result of 45 Ca tracer experiments it was shown that calcium is taken up from the earthworm via body fluids: the tracer was taken up promptly by the cells and was led to the gland cavity in order to start the accumulation of the biospheroid (NAKAHARA, H. -BEVELANDER, G. 1969).…”