. Foundations of botany. Botany; Botany. FERTILIZATION 215 the ovule m, in Fig. 165, reaches one of the cells shown at e, and transfers a generative cell into this egg-cell. The latter is thus enabled to divide and grow rapidly into an embryo. This the cell does by forming cell-walls and then in- creasing by continued subdivision, in much the same way in which the cells at the growing point near the tip of the root, or those of the cambium layer, subdivide.^ 227. Nature of the Fertilizing Process.— The necessary feature of the process of fertiliza- tion is the union of the essential contents o
. Foundations of botany. Botany; Botany. FERTILIZATION 215 the ovule m, in Fig. 165, reaches one of the cells shown at e, and transfers a generative cell into this egg-cell. The latter is thus enabled to divide and grow rapidly into an embryo. This the cell does by forming cell-walls and then in- creasing by continued subdivision, in much the same way in which the cells at the growing point near the tip of the root, or those of the cambium layer, subdivide.^ 227. Nature of the Fertilizing Process.— The necessary feature of the process of fertiliza- tion is the union of the essential contents of two cells to form a new one, from which the fwtiire plant is to spring. This kind of union is found to occur in many cryp- togams (Chapters XX-XXII), resulting in the production of a spore capable of grow- ing into a complete plant like that which produced it. 1 See Kerner and Oliver's Natural History of Plants, Vol. II, pp. Fig. 165. — Diagranmiatic Bepresentation of Fertilization of an Ovule. i, inner coating of ovule ; o, outer coating of ovule; _p, pollen tube, proceeding from one of the pollen grains on the stigma ; c, the place where the two coats of the ovule blend. (The kind of ovule here shown is inverted, its opening m being at the bottom, and the stalk / adhering along one side of the ovule.) a to c, embryo sac, full of pro- toplasm ; a, so-called antipodal cells of em- bryo sac; n, central nucleus of the embryo sac; c, nucleated cells, one of which, the egg-cell, receives the essential contents of the pollen tube; /, funiculus or stalk of ovule; m, opening into the Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Bergen, Joseph Y. (Joseph Young), 1851-1917; Eastwood, Alice, 1859-1953. Boston, Ginn & Co.
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectbotany, bookyear1901
