01812naa a2200205 a 450000100080000000500110000800800410001902400300006010000230009024500680011326000090018152012740019065000130146465000150147765000100149265000120150265300110151470000180152577300630154318347172019-01-28       1952    bl ---       0--  u    #d7 aDOI: 10.2307/24387032DOI1 aKIESSELBACH, T. A.  aStructure of certain specialized tissues in the kernel of corn.  c1952  aThe development and structure of the pericarp, semipermeable membrane, and closing tissue of the corn kernel were found to differ but slightly from previous descriptions. Microchemical tests were applied to determine as far as possible the specialized modification of these tissues. Two nutritive mechanisms develop in the growing corn seed. One is a modification of the basal endosperm. The outermost cells become specialized as an absorbing layer. Their dense protoplasm contains heavy longitudinal strands and the walls are marked by longitudinal thickenings. Inward from this layer is a region of elongated, highly protoplasmic, conducting cells whose walls are marked by spiral and reticulate thickenings. The other nutritive structure is the scutellum, specialized for digestion and absorption. By enlargement it crushes the basal endosperm as maturity is approached. Its outermost cells become an absorbing layer. They are chacterized by a slight thickening of the anticlinal walls and by abundant protoplasm. The parenchyma cells of the scutellum develop heavily thickened walls which are marked by large simple pits. The relation of the various absorbing, conducting and protective tissues to the nutritional and moisture economy of the corn seed is discussed.  aAnatomia  aHistologia  aMilho  aSecagem  aGrãos1 aWALKER, E. R.  tAmerican Journal of Botanygv. 39, n. 8, p. 561-569, 1952.