• Journal of Plant Biology
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• v.38 no.3
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• pp.275-280
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• 1995

The formation of osmiophilic globules related to the granal lysis has been investigated with a shade plant ginseng (Panax ginseng C. A. Meyer) exposed to full sunlight. The changes of chloroplast were examined as a function of time over 9 days under full sunlight exposure. The ultrastructure of ginseng leaf showed swelling of the granal thylakoid during an early stage of the light exposure. The thylakoid membrane faded and small electron-opaque dots were aggregated on the edges of the granal thylakoid membrane when the exposure time was increased over 1 day. Then, the sahpe of the grana changed into round. After the exposure over 3 days, there appeared many osmiophilic globules with multi-lamellated concentric structure. The globules at this stage were partly accumulated with osmiophilic substances. The outermost membrane of these multi-lamellated osmiophilic globules was attached to the stromal thylakoid membrane connecting to the deforming grana. The osmiophilic globules were elongated after 9 days. In this stage, the multi-lamellated structure was difficult to identify due to severe accumulation of osmiophilic substances. The number of the osmiophilic globules also increased along with the full sunlight exposure time. This observation leads us to believe that the multi-lamellated osmiophilic globules came from the deformation of grana.

• Journal of The Korean Astronomical Society
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• v.40 no.4
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• pp.127-129
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• 2007

It is well known that water vapor maser emission at 22.2 GHz is associated with the earliest stages of both low- and high-mass star formation and it can be considered a reliable diagnostic of their evolutionary state. Bright Rimmed Clouds (BRCs) are clouds that have been compressed by an external ionization-shock front which focuses the neutral gas into compact globules. The boundary layer between the neutral gas and the gas ionized by the incident photons is often called "bright rim" but the clumps are sometimes classified also as speck globules or cometary globules depending on their appearance. Small globules with bright rims have been considered to be potential sites of star formation and have been studied in several individual regions. We present results from high resolution VLA observations searching for new candidates of recent star formation in bright-rimmed clouds/globules associated with IRAS point sources.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.197-198
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• 1996

We have carried out $^{13}CO$ J = 1 $\to$ 0 line observations with spatial resolution of 2' toward 17 small globules selected from the catalogue of Clemens & Barvainis (1988) with a selection criterion of [b] $\ge$ 15 degrees using the Nagoya 4-m radio telescope. Overall characteristics and physical parameters are presented and discussed by examining the $^{13}CO$ integrated intensity map for each of the globules.

• Journal of the Mineralogical Society of Korea
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• v.9 no.2
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• pp.64-70
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• 1996

Early weathering products of anorthosite were investigated by using scanning electron microscopy in order to trace the development of halloysite particles and aggregates. Tiny short tubes or spheres precipitate on the plagioclase surface in the initial stage of weathering and form the compact globular aggregates. With continued growth, several globules are coalesced into wrinkled halloysite aggregates, and short tubes or spheres in globules grow into long tubes forming sheaf-like aggregates. Particle shape of halloysite varies with changing supersaturation degree of weathering solution, and determines the morphology of halloysite aggregates.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.5
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• pp.1231-1243
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• 2016

The ultrastructural study on oocyt development and the process of vitellogensis in the oocytes during oogenesis in female Pampus echinogaster were investigated by electron microscope observations. In the previtellogenic phase, in particular, several intermitochondrial cements appear in the cytoplasms of the chromatin nucleleolus oocyte and perinuclear oocyte. The number of intermitochondrial cements are associated with the multiplication of the number of mitochondria in the early developmental stage. In the early vitellogenic phase, the Golgi complex in the cytoplasm of the yolk vesicle oocyte is involved in the formation of yolk vesicles containing carbohydrate yolks. At this time, many pinocytotic vesicles containing yolk precursors (exogenous substances) by pinocytosis are observed in the cytoplasm near the region of initial formation of the zona pellucida. In the late vitellogenic phase, two morphological different bodies, which formed by the modified mitochondria, appeared remarkably in the yolked oocytes. The one is the multivesicular bodies and another is yolk precursors. The multivesicular bodies were transformed into the primary yolk globules, while yolk precursors were connected with exogeneous pinocytotic vesicles near the zona pellucida. After the pinocytotic vesicles were taken into yolk precursors, the yolk precursors were transformed into the primary yolk globules. Thereafter, primary yolk globules mixed with each other, eventually, they developed into secondary and tertiary yolk globules. In this study, vitellogenesis of this species occurred by way of endogenous autosynthesis and exogenous heteogenesis. Vitellogenesis occurred through the processes of endogeneous autosynthesis, involving the combined activity of the Golgi complex, mitochondria and multivesicular bodies formed by modified mitochondria. However, the process of heterosynthesis involved pinocytotic incorporation of extraovarian precursors (such as vitellogenin in the liver) into the zona pellucida (by way of granulosa cells and thecal cells) of vitellogenic oocytes.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.119.1-119
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• 2003

The glyoxysomal nature of microbodies was determined in Botryosphaeria dothidea hyphae based on morphology and in situ enzyme characteristics by transmission electron microscopy and cytochemistry. Bound by a single membrane, microbodies had a homogeneous matrix and varied in size ranging from 200 to 400 m in diameter. Microbodies had crystalline inclusion(s) which consisted of parallel arrays of fine tubules in their matrices. Microbodies and lipid globules were frequently placed in close association with each other, forming microbody-lipid globule complexes in hyphae. The cytochemical activities of catalase and malate synthase were localized in matrices of microbodies, showing intense electron-density of the organelle. In addition, the immunogold labeling detected the presence of catalase in multivesicular bodies and hyphal cell walls as well as in matrices and crystalline inclusions of microbodies, supporting the enzyme secretion through cell walls. Meanwhile, isocitrate Iyase was localized only in matrices of microbodies. These results suggest that microbodies, particularly complexed with lipid globules, in the fungal hyphae are functionally defined as glyoxysomes, where glyoxysomal enzymes are biochemically active for the glyoxylate cycle to be a metabolic pathway in gluconeogenesis. (Mycology and Fugus Diseases)

• Animal cells and systems
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• v.13 no.1
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• pp.49-57
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• 2009

For the study of the reproductive mechanism associated with the process of vitellogenesis, oocyte development and vitellogenesis during oogenesis in female Boleophthalmus pectinirostris were investigated by electron microscopic observations. The ovary consists of a pair of saccular structures with many ovarian lobules. In the early vitellogenic oocyte, the Golgi complex plays an important role leading to the formation of yolk vesicles containing carbohydrate yolks. At this time many pinocytotic vesicles containing yolk precursors are observed in the cytoplasm near the region of initial formation of the zona radiata. In the late vitellogenic oocytes, the multivesicular bodies, which are formed by modified mitochondria, are involved in the formation of the primary yolk granules. Precursors of yolk granules and multivesicular bodies develop to primary yolk globules with participation of pinocytotic vesicles. After primary yolk globules mix with each other, they develop into secondary and tertiary yolk globules. Based on these findings, vitellogenesis of B. pectinirostris occurs by way of the processes of endogenous autosynthesis and exogenous heterosynthesis. The process of autosynthesis involves the combined activity of the Golgi complex, mitochondria, and multivesicular bodies. However, the process of heterosynthesis involves pinocytotic incorporation of extraovarian precursors into the zona radiata of vitellogenic oocytes by way of the thecal cell layers and granulosa cells.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.6
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• pp.736-752
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• 1995

Fine structural changes of germ cell during the gametogenesis of Korean rockfish, Sebastes schlegeli sampled in west coast of Korea were investigated from September 1993 to August 1994. In a layer of microvilli of oocyte with active yolk duplication, many pinocytotic vesicles containing protein granules regarded as yolk precursors were observed. The multivesicular bodies were formed by gathered mitochondria. They are participated in formation of the primary yolk globules homogeneously filled with high dense particles and enclosed within a limiting membrane. The precursors of yolk globule appeared to be formed by modification of mitochondria and they developed into the primary yolk globules with participation of large and dense pinocytotic vesicles. Yolk globules in mature oocyte were consisted of three components: the crystalline type main body, the superficial layer with dense and fine granules, and the limiting membrane. Steroid hormone secreting cells were recognized in the interstitial cells of growing testis. Numerous endoplasmic reticula and large mitochondria with well developed tubular cristae appeared in their cytoplasms. The axoneme in the tail flagellum of spermatozoon consisted of nine pairs of microtubules at the periphery and one pair at the center, and they were covered with doublet microtubules.

• The Bulletin of The Korean Astronomical Society
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• v.18
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• pp.23.2-24
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• 1993

• The Bulletin of The Korean Astronomical Society
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• v.9
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• pp.10.1-10.1
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• 1984