. The cytoplasm of the plant cell. Plant cells and tissues; Protoplasm. Chapter XIX 209 Cytoplasmic Alterations that of nuclear autochromatism reported in certain cells whose vacuoles contain anthocyanin (P. A. Dangeard, Moreau, Guillier- MOND). These writers observed that at the moment of death of these cells, the vacuoles lose their color and the pigment becomes localized in the cytoplasm and especially in the nucleus. This phe- nomenon is observed particularly in the final stages of plasmolysis. Becquerel advocates the use of a mixture of neutral red and methylene blue. Neutral red stains t
. The cytoplasm of the plant cell. Plant cells and tissues; Protoplasm. Chapter XIX 209 Cytoplasmic Alterations that of nuclear autochromatism reported in certain cells whose vacuoles contain anthocyanin (P. A. Dangeard, Moreau, Guillier- MOND). These writers observed that at the moment of death of these cells, the vacuoles lose their color and the pigment becomes localized in the cytoplasm and especially in the nucleus. This phe- nomenon is observed particularly in the final stages of plasmolysis. Becquerel advocates the use of a mixture of neutral red and methylene blue. Neutral red stains the vacuoles of living cells and the less penetrating methylene blue colors only the cytoplasm of dead cells. The examination of the cells with the ultramicro- scope, as has been seen, makes it easily possible to determine the moment when the cell dies. As soon as death occurs, , the coagulation of the cytoplasm, one witnesses a series of phenomena, designated as autolysis, which consist of an autodigestion of the protoplasm under the action of intracellular proteo- lytic enzymes. The enzymes, whose ac- tion is no longer inhibited, induce modi- fications in the cell, characteristic of degeneration, , cellular necrobiosis. This consists essentially of an autoly- sis, , of a digestion, starting in the interior of the cell itself and instigated by the enzymes. These enzymes, al- though present during life, do not act on living material because of some still unknown mechanism. The modifications generally pro- duced in the cell take the form of more and more marked vesiculation of the chondriosomes and plastids, bringing about the alveolar structure described by BiJTSCHLi. The mitochondrial vesi- cles, which are often enormous, sometimes finally burst. Their wall then breaks up into an infinity of small refractive granules which are scattered about in the cell. In its turn, the vacuole ceases to exist when the perivacuolar membrane is destroyed. This leads to a contractio
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