The ultrastructure of the nauplius eye ofSapphirina (Crustacea: Copepoda)
The ultrastructure of the nauplius eye ofSapphirina (Crustacea: Copepoda)
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蓝宝石无节幼体眼的超微结构（甲壳纲：桡足类）
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发表时间：
1969
期刊：
影响因子：
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通讯作者：
R. Elofsson
中科院分区：
文献类型：
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作者：
R. Elofsson
对三种桡足类无节幼体的特化眼进行了超微结构研究。证实了先前描述的大体形态（Elofsson，1966 a）。腹杯被红色色素覆盖，侧杯被红色和黑色色素覆盖。两种色素细胞色素颗粒的超微结构不同。此外，黑色素细胞含有大量的横向带状原纤维，能够产生反射晶体。黑色素细胞的色素颗粒显示出电子密度的变化。侧杯中的黑色色素细胞和大小网膜细胞之间存在密切的连接，表明物质交换。存在于所有三个杯中的绒毡层细胞形成包含在两套膜中的晶体片。腹侧杯和部分侧杯的功能可能与胸眼有关（Land，1965）。小网膜细胞的杆粒由400 μ m的微绒毛组成。这些的取向似乎排除了极化行为。腹杯和侧杯的四个小细胞含有一些小网膜细胞，其微绒毛平行于入射光排列。小网膜细胞进一步发展出一个复杂的膜内陷系统，深入细胞内部，并与许多线粒体相连。腹杯和侧杯的部分的视网膜细胞含有明确的部分充满颗粒状物质。视网膜和其他细胞含有具有平行小管的减弱的线粒体。每个侧杯前面的近端透镜由一个单元组成。建议从结膜细胞发育而来。的功能和演变的结果进行评估。
SummaryThe ultrastructure of the specialized nauplius eye of three species of the copepod genusSapphirina was investigated. The gross morphology described earlier (Elofsson, 1966a) was confirmed. The ventral cup is covered by a red pigment and the lateral cups by a red and a black pigment. The ultrastructural configuration of the pigment granules was found to differ in the two kinds of pigment cells. The black pigment cell, moreover, contains a large number of transversely banded fibrils and is able to produce reflecting crystals. The pigment granules of the black pigment cell show a variation in electron density. An intimate connexion exists between the black pigment cell and large retinula cells in the lateral cups, indicating an exchange of material. The tapetal cells present in all three cups form crystal platelets contained in two sets of membranes. It is suggested that the ventral cup and part of the lateral cups function as thePecten-eye (Land, 1965). The rhabdomeres of the retinula cells are composed of microvilli measuring 400 Å. The orientation of these seems to exclude polarotactic behaviour. The ventral cup and the four small cells of the lateral cups contain some retinula cells with microvilli arranged parallel to the incoming light. The retinula cells further develop an intricate system of membrane-invaginations penetrating deep into the cell and associated with numerous mitochondria. Retinula cells of the ventral cup and part of the lateral cups contain clear portions filled with granular material only. Retinula and other cells contain attenuated mitochondria with parallel tubuli. The proximal lens in front of each lateral cup consists of one cell. A development from the conjunctival cells is suggested. The results are evaluated in terms of function and evolution.