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1.
There are many reports that cells (protoplasts) separated from the thallus ofPorphyra by enzyme can develop to normal leafy thalli in the same way as monospores. But there are few investigations on the subcellular
structure of the isolated vegetative cell for comparison with the subcellular structure of monospores. To clarify whether
the separated and cultured cells undergo the same or similar ultrastructure changes during culture and germination as monospores
undergo in their formation and germination, we observed their ultrastructure, compared them with those of the monospore and
found that the ultrastructure of separated and cultured cells did not have the characteristic feature as that of monospore
formation, such as production of small and large fibrous vesicles, but was accompanied by vacuolation and starch mobilization
like that in monospore germination. The paper also discusses the relations between monospores and separated and cultured cells.
Contribution No. 3875 from the Institute of Oceanology, Chinese Academy of Sciences.
Project 39770593 supported by NSFC; Project 96-C01-05-01 of the 9th Five-Year Plan supported by Science and Technology Commision
of China. 相似文献
2.
It had been demonstrated that individual cells or protoplasts isolated from Porphyra thallus by enzyme could develop into normal leafy thalli in the same way as monospores, and that isolated cells develop in different way in liquid and on semi solid media. The authors observed the ultrastructure of isolated vegetative cells cultured on semi solid media and compared them with those of monospores and isolated cells cultured in liquid media. The results showed that subcellular structures were quite different among cells in different conditions. In their development, isolated cells on semi solid media did not show the characteristic subcellular feature of monospore formation, such as production of fibrous vesicles. Callus like cells formed on semi solid media underwent a distinctive modification in cellular organization. They developed characteristic cell inclusions and a special 2 layer cell covering. Golgi bodies, ER, starch grains, mitochondria. Vacuoles were not commonly found in them. 相似文献
3.
ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｓｉｎｇｌｅｃｅｌｌｓａｎｄｐｒｏｔｏｐｌａｓｔｓｏｆＰｏｒｐｈｙｒａｇａｍｅｔｏｐｈｙｔｅｂｌａｄｅｓｃｏｕｌｄｄｅｖｅｌｏｐｉｎｔｏｐｌａｎｔｌｅｔｓｄｉ ｒｅｃｔｌｙｏｒｉｎｔｏｃａｌｌｕｓ ｌｉｋｅｃｅｌｌｓ (ＺｈａｏａｎｄＺｈａｎｇ ,1 981 ;Ｐｏｌｎｅ Ｆｕｌｌｅｒｅｔａｌ.,1 984 ;Ｃｈｅｎ ,1 989;ＷａｎｇａｎｄＹａｎ ,1 990 ;Ｇａｌｌｅｔａｌ.,1 993;Ｃｈｅｎ ,1 997;ＭｅｉａｎｄＦｅｉ,2 0 0 1 ) ,ａｎｄｔｈｅｉｒｇｒｏｗｔｈａｎｄｄｅｖｅｌｏｐｍｅｎｔｕｎｄｅｒ… 相似文献
4.
It had been demonstrated that individual or protoplasts isolated from Porphyra thallus by enzyme could develop into normal leafy thalli in the same way as monosproes,and that isolated cells develop in different way in liquid and on semi-solid media,The authors observed the ultrastructure of isolated vegetative cells cultured on semi-solid media and compared them with those of monospores and isolated cells cultured in liquid media,The results showed that subcellular struce-tures were quite different among cells in different conditions.In their development,isolated cells on semi-solid media did not show the characteristic subcellular eature of monospore formation ,such as production of fibrous vesicles,Callus-like cells formed on semi-solid media underwent a distinctive modification in cellular organization.They developed characteristic cell inclusions and a special 2-layer cell covering,Golgi bodies,ER ,starch grains,mitochondria,Vaculoes were not commonly found in them. 相似文献
5.
Porphyra haitanensis andP. yezoensis are two mainPorphyra species cultured in China. Their life histories are slightly different. So far we have not observed thatP. haitanensis naturally produces monospores developing into thalli.P. yezoensis produces monospores which directly germinate into young thalli used in cultivation (Zeng, et al., 1985). Some somatic cells
inP. yezoensis develop in vitro into monospore-like cells which later grow into young thalli (Lu, 1983). Studies on whether or not somatic
cells inP. haitanensis can produce in vitro monospore-like cells that later grow into young thalli is important for understanding its life history
and for culturing new varieties. 相似文献
6.
Yan Gao Tao Zhang Libin Zhang Tianlong Qiu Dongxiu Xue Hongsheng Yang 《中国海洋大学学报(英文版)》2014,13(6):1071-1077
Spionid worms of Polydora ciliata inhabit the shells of many commercially important bivalves and cause disease in molluscan aquaculture. Their sperm structure is closely related to their fertilization method. To give an insight into the sperm structure and spermatogenesis, ultrastructure details of the subcellular components of germ cells during spermiogenesis of Polydora ciliata are detected by transmission electron microscopy (TEM). In P. ciliata, during spermiogenesis, chromatin is regularly arranged as dense fibrils and becomes more condensed when the nucleus elongates. Microtubules do not surround the nucleus during its elongation. The Golgi phase is characterized by the formation of proacrosomal granules within the Golgi apparatus. The proacrosomal granules fuse to form a single, spherical acrosomal vesicle that migrates to the anterior pole of the cell. At the time of nuclear condensation, mitochondria become reduced in number but increased in size, causing deep indentation at the base of the nucleus. The mid-piece has a few mitochondria. The cap phase includes the spreading of the acrosomal granule over the surface of the nucleus of the differentiating spermatid. The acrosomal phase of spermiogenesis is typically associated with changes in the shape of the nucleus, acrosome and tail. The relationship of sperm ultrastructure to spermiogenesis in spionidae species was discussed. 相似文献
7.
魏印心 《中国海洋湖沼学报》1994,(2)
The morphology and reproduction cycles of a new species,Zygnemopsis hubeiensis Wei are describedand illustrated for a culture homothallic strain collected from Wuhan,Hubei,China.The asexual reproduction is by parthenospores,aplanospores and akinetes.The major events of the sexual cycle,including the genuflection of reproductive cells,gametangial development,gamete formation,gamete fusion,zygote formation,zygospore development,and zygospore germination are observed. 相似文献
8.
小秦岭区域复背形南侧的“秦仓沟组”,原定为一套混合岩和混合岩化变质岩,划属太华群的上部组元.近年经研究确认为具典型韧性变形的动力学标志的古老糜棱岩带,是在左行走滑的强烈挤压条件的深层塑性变形产物,从而肯定了太华群南侧也与北侧一样,为古韧性剪切带所围限.结合实际资料提出了对太华群划分方案的意见.太华群边缘韧性剪切带的发现,对小秦岭区域地质构造发展演化的认识具重要意义,开辟了认识区域构造格局和金矿分布规律的新思路. 相似文献
9.
We present results on the effect of modified clay on cyst formation of Scrippsiella trochoidea in harmful algal bloom （HAB）. Modified clay （in concentration of 0, 0.1, 0.5, and 1.0 g/L） were added to cultures, and observations were made on cysts of S. trochoidea under controlled laboratory conditions. Results indicate that the removal rate of algal cells reached 97.7% at the clay concentration of 1.0 g/L. The cyst formation rate increased from 4.6% to 24.6% when the concentration of clay was increased from 0 to 1.0 g/L. Two cyst metamorphs were observed： spinal calcareous cysts and smooth noncalcareous ones. The proportion of the spinal cysts decreased from 76.9% to 24.1% when clay concentration increased from 0 to 1.0 g/L. In addition, modified clay affected cyst germination. The germination rate decreased with the increases in the clay concentrations. Non-calcareous cysts had a lower germination rate with a longer germination time. We conclude that modified clay could depress algal cell multiplication and promote formation of temporal cysts of S. trochoidea, which may help in controlling HAB outbreaks. 相似文献
10.
《中国海洋湖沼学报》2014,(6)
We present results on the effect of modified clay on cyst formation of Scrippsiella trochoidea in harmful algal bloom(HAB).Modified clay(in concentration of 0,0.1,0.5,and 1.0 g/L) were added to cultures,and observations were made on cysts of 5.trochoidea under controlled laboratory conditions.Results indicate that the removal rate of algal cells reached 97.7%at the clay concentration of 1.0 g/L.The cyst formation rate increased from 4.6%to 24.6%when the concentration of clay was increased from 0to 1.0 g/L.Two cyst metamorphs were observed:spinal calcareous cysts and smooth noncalcareous ones.The proportion of the spinal cysts decreased from 76.9%to 24.1%when clay concentration increased from0 to 1.0 g/L.In addition,modified clay affected cyst germination.The germination rate decreased with the increases in the clay concentrations.Non-calcareous cysts had a lower germination rate with a longer germination time.We conclude that modified clay could depress algal cell multiplication and promote formation of temporal cysts of 5.trochoidea,which may help in controlling HAB outbreaks. 相似文献
11.
Wei Yin-xin 《中国海洋湖沼学报》1994,12(2):180-184
The morphology and reproduction cycles of a new species,Zygnemopsis hubeiensis Wei are described and illustrated for a culture homothallic strain collected from Wuhan, Hubei, China. The asexual reproduction
is by parthenospores, aplanospores and akinetes. The major events of the sexual cycle, including the genuflection of reproductive
cells, gametangial development, gamete formation, gamete fusion, zygote formation, zygospore development, and zygospore germination
are observed. 相似文献
12.
陶湾群分布于洛南—栾川一带,分三个自然段出露。本文描述了各地段陶湾群代表性剖面,论述了层序划分和区域对比。文中依据地层接触关系、古生物资料以及同位素地质年龄,确定陶湾群的时代为奥陶纪。 相似文献
13.
刘代志 《地球科学与环境学报》1988,(2)
本文较全面地探讨了东南地洼区反映深部构造特点的地球物理特征(波速结构,地温分布,电性,密度,重、磁场异常),综合分析了该区地洼构造形成、演化的力源机制,讨论了地洼构造与板块构造的力源机制关系问题。 相似文献
14.
LOCALIZATION OF A PUTATIVE EPIBOLY-DETERMINING FACTOR IN OOCYTES OF THE GOLDFISH (CARASSIUS AURATUS)
It is unknown whether cytoplasmic determinants in goldfish eggs are asymmetrically localized beforematuration. In this study fully grown goldfish oocytes with infact germinal vesicles (GVs) were ligated withbaby hair loops along desired planes into two parts, mature in vitro, and inseminated. Embryos developedfrom the animal halves with GV of oocytes ligated along the equator un unable to undergoepiboly, while those developed from the GV-containing parts of oocytes ligated along the animal-vegetal axiswere able to. Also, embryos developed from the animal halves obtained from fertilized eggs could undergo epiboly. From there results, it was postulated that the goldfish's premature oocyte possessed a putativefactor in the vegetal hemisphere which was responsible for epiboly of the embryonic cells. 相似文献
15.
杜晓东 《广东海洋大学学报》1998,(3)
利用透射电镜观察九孔鲍（Haliotidaediversicoloraquatilis）的外套膜表皮细胞,结果表明细胞可分为4大类,即普通柱状表皮细胞、嗜碱性粒细胞、嗜酸性粒细胞和感觉细胞。它们在不同区域的分布、形态和数量变化与外套膜的功能分化密切相关。 相似文献
16.
张伯声 《地球科学与环境学报》1987,(1)
地球在宇宙中犹如太沧一粟或大海一滴,每粒每滴都是太沧与大海的一个分子,它们无时不在结合与分散之中。这种结合与分散是在同地、同时、辩证地发展着的。所有的星体都松散地结合在一起。实际上,它们是随地随时变化着的,这种变化服从于宇宙的斜向运动,因此地质构造具有普遍的斜向性。 相似文献
17.
ZHU Jie ZHANG Xiumei and GAO Tianxiang Fisheries College Ocean University of China Qingdao P.R.China 《中国海洋大学学报(英文版)》2005,4(2)
Histological development of Japanese flounder Paralichthys olivaceus larval skin and ultrastructural difference of skin between reared normal and malpigmented Japanese flounder were studied with light microscopy (LM) and transmission electron microscopy (TEM). The results show that the skin develops slowly before the metamorphosis, while at the onset of metamorphosis, the skin develops quickly and becomes complete in structure till about 50d after being hatched. Ultrastructural observation on the normal and malpigmented skins shows that the iridophore and melanophore are adjacent to each other. Profile and structure of the two kinds of pigment cells are more complete in the skin of normal ocular side than in the skin of pigmented blind side. The ultrastructure of typical chloride cell was observed in the skin of Japanese flounder larvae for the first time. 相似文献
18.
冉兴龙 《地球科学与环境学报》2003,25(4):55-59
给出了非固结储水层的质量守恒方程在不同假定条件下的简化形式及其物理意义,并揭示水的非稳定渗流与储水层形变之间的相互因果关系及形变量与储(释)水量之间的体积交换关系.通过垂向弹性形变假定下,储水层形变质量守恒方程与渗流方程的耦合分析发现,细粒储水层由于水头变化导致骨架对水的弹性储存或释放而引发的任一点处的垂向应变,等于其储水层的总弹性储(释)水率或骨架弹性储(释)水率与水头增量的乘积,该公式实际上为计算地面沉降的分层总和法提供了基本理论依据. 相似文献
19.
ZHUJie ZHANGXiumei GAOTianxiang 《中国海洋大学学报(英文版)》2005,4(2):145-151
Histological development of Japanese flounder Paralichthys olivaceus larval skin and ultrastructural difference of skin between reared normal and malpigmented Japanese flounder were studied with light microscopy (LM) and transmission electron microscopy (TEM). The results show that the skin develops slowly before the metamorphosis, while at the onset of metamorphosis, the skin develops quickly and becomes complete in structure till about 50d after being hatched. Ultrastructural observation on the normal and malpigmented skins shows that the iridophore and melanophore are adjacent to each other. Profile and structure of the two kinds of pigmcnt cells are more complete in the skin of normal ocular side than in the skin of pigmented blind side. The ultrastructure of typical chloride cell was observed in the skin of Japanese flounder larvae for the first time. 相似文献
20.
Results of a series of experiments(on the adsorption of divalent metal ions by dried alginic acid, Na and Ca alginates of different composition and block structure) conducted in this systematic study of the effects of the composition and structure of alginates on the static adsorption equilibrium of divalent metal ions indicate that the properties of alginate adsorption to divalent metal ions are highly different, depending not only on the cations used, but also on the form and structure of the alginates. There is close correlation between the adsorption properties and the structure of the alginates. The selectivity coefficient of Na alginate for Cd-Sr ion exchange tends to increase with the increase of the M/G ratio in alginate, whereas the adsorption capacity of Ca alginate for Cu~(2+) ion decrease with the increase of the G-block or the average length of the G-block ((?)_G) and the total adsorption capacity of alginic acid is found to vary in the same order as the F_(MM)(diad frequency) in alginate in 相似文献