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81.
In sweet pepper, the portion of tapetum toward the interior of the anther comprising large cells is derived from cells of connective of anther whereas the remaining tapetum on the outside of the anther comprising comparatively small cells is derived from the parietal layer. Those ceils of the former prosessing large vacuoles and large nuclei are stained weaker than the cells of the latter by methyl green-pyronin and mercuric-bromophenol blue staining. Large spherical grains which contain acid phosphatase appear in the vacuoles in both kinds of tapetum at sporogenesis stage. During meiosis of pollen mother cells, DNA, RNA and protein sysntheses increase in tapetum. The tapetum derived from connective accumulates more DNA than that derived from parietal layer. The activity of acid phosphatase becomes higher in tapetum when it degenerates. The degeneration of two kinds of tapetum is similar. There are no starch grains in tapetum through its whole course of development.  相似文献   
82.
The development of the tapetum in Ophiopogon ]aponicus is of secretory type Tapetum develops at their peak during the microspore mother cell stage. There are abundant organelles, consisting of a lot of mitochondria, dictyosomes and plastids, especially endoplasmic reticulum. Pro-Ubisch bodies e. merge as early as at the stage of microspore mother cell. At tetrad stage, a large number of pro-Ubisch bodies accumulate between inner tangential face of the plasmalemma and the cell wall. At the early microspore stage, pro-Ubisch bodies are distributed in the small embayments of the plasmalemma. As the sporopollenin begins to deposit on them, proubisch bodies develop into Ubisch bodies which consist of two types: single and aggregated. Tapetal cells degenerate completely when pollen grains reach maturity.  相似文献   
83.
Summary We have confirmed that the LLA-15 polypeptide ofLilium longiflorum is (a) tapetum specific with some expression possible in the adjacent middle layer cells and (b) relatively abundant as evidenced by the high density of gold particles localized to the tapetal cells. We have established that the protein is cytoplasmic and not associated with organelles, membranes, extracellular matrix or wall. We also report an amino acid composition of the molecule and a partial sequence which bears no resemblance to any protein yet described.Abbreviations BSA bovine serum albumin - PMSF phenyl methyl sulfonyl fluoride  相似文献   
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