. The cytoplasm of the plant cell. Plant cells and tissues; Protoplasm. Chapter VII 61 — The Chondriome ^r\ ^ o ^ „ o o o O - o _ o Qa numerous, densely clustered, chondrioconts. Then the cell under- goes a nuclear fusion and when that is completed, the two chondrio- somal masses fuse around the single nucleus. After nuclear fusion, the ascus enlarges and grows longer progressively to form an elongated voluminous cell. During this process, the nucleus main- tains a somewhat central position while the chondrioconts, which have been grouped about the nucleus, spread out through the entire cytopl
. The cytoplasm of the plant cell. Plant cells and tissues; Protoplasm. Chapter VII 61 — The Chondriome ^r\ ^ o ^ „ o o o O - o _ o Qa numerous, densely clustered, chondrioconts. Then the cell under- goes a nuclear fusion and when that is completed, the two chondrio- somal masses fuse around the single nucleus. After nuclear fusion, the ascus enlarges and grows longer progressively to form an elongated voluminous cell. During this process, the nucleus main- tains a somewhat central position while the chondrioconts, which have been grouped about the nucleus, spread out through the entire cytoplasm which in this phase is filled with small vacuoles. At the same time, at one or several points on their long axis, the chondrio- conts usually form small swellings, each occupied by a vesicle (Fig. 28). When the growth of the ascus is complete, but a little before the first mitosis occurs, these vesicles disappear and the chon- drioconts, all oriented in the direction of the longitudinal axis of the cell, manifest a tendency to elongate. At this stage a cytoplasm (sporoplasm), dense and rich in chondrioconts, differentiates in the central region of the ascus while the basal and apical portions des- tined to make up the epiplasm, re- main filled with small vacuoles. The nucleus which occupies the center of the sporoplasm then undergoes three successive mitoses during which, it is seen, the chondrioconts remain scattered in the sporoplasm except in the region occupied by the asters where they are completely absent. The divisions completed, each of the resulting eight nuclei remains con- nected with its aster by a small pro- tuberance at the end of which the centrosome still persists. It is not long before the astral fibres them- selves recurve so that, in section, each nucleus then appears as if surmounted by a parasol on whose surface there will first form the limiting membrane of the future ascospore. Now the whole region of the future spore occupied by the centrosome an
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Keywords: ., bookcentury1900, bookcollection, booksubjectplantcellsandtissues
