• Applied Microscopy
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• 제28권4호
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• pp.513-525
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• 1998

The spermatogenetic process in the edible giant snail is similar to those in the other snails, except for the axoneme formation process. In this study, the axoneme formation process in the giant snail was mainly examined by means of electron microscopy. The tail portion of a spermatozoon is about $160{\mu}m$ long, and extends straight to the rear, surrounded by two large and long mitochondria in spiral forms. A number of glycogen particles $(40\sim70nm)$ are found in the swollen matrix of the mitochodria. The axoneme which composes the tail of a spermatozoon is surrounded by $7\sim10$ lamella-form fibrous sheaths of about $0.2{\mu}m$ in thickness. Most of the mature spermatozoa are found to be clustered into a group of $5\sim7$ ea in syncytial bridges formed by cytoplasmic processes. Sertoli cells contain glycogen particles, endoplasmic reticulum, a lot of mitochondria, and lipids in their cytoplasm. They protrude their filiform pseudopodia and phagocytize abnormal spermatids or spermaozoa.

• Applied Microscopy
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• 제26권1호
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• pp.33-45
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• 1996

The spermatogenesis of Korean slug, Incilaria fruhstorferi are observed by electron microscope. The results are as follows: The spermatogenesis of Korean slug, Incilaria fruhstorferi, is processed through the five stages; Spermatogonia, primary spermatocyte, secondary spematocyte, spermatid and spermatozoon. The spermiogenesis, the differentiation of the spermatid, is also processed through the five stages. In stage 1, the numerous and round mitochomdria in the cytoplasm are moved around the nucleus of spermatid. In stage 2, the nucleus of spermatid transformed into the oval shape, and the oval nucleus is surrounded by many rough endoplasmic reticulum. In stage 3, the oval nucleus of spermatid is changed to be curved as an arrow, and then two centrioles appeared behind nucleus. The centriole is sucked into the cytoplasm. and almost all the chromatins are changed into heterochromatins. In stage 4, the nucleus of spermatid are transformed into the oval shape, when the lamella plate chromatin of spermatid form in the nucleoplasm. In stage 5, the oval nucleus is then transformed into the stream-line shape when the lamella plate chromatin of spematid gradually concentrated in the nucleus, and long axoneme ($65{\mu}m$ in length) form from the distal centriole. Two long mitochondria in the middle piece and the main piece of spermatozoon array spirally along a long axoneme, and the mitochondria matrix is gradually filled with electron-dense glycogen particles ($0.1{\mu}m$ in size). The axoneme of spermatozoon consists of typical 9+2 microtubular pattern.

• Fisheries and Aquatic Sciences
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• 제10권4호
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• pp.196-199
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• 2007

The spermatozoa of Leiocassis nitidus are relatively simple cells composed of a spherical head, a short midpiece, and a tail, as in most Siluriformes. The ultrastructure is characterized by the following features: Acrosome absent, as in most teleosts; around nucleus about $1.8\;{\mu}m$ long, with a deep nuclear fossa containing the proximal and distal centrioles and mitochondria. Two centrioles approximately $180^{\circ}$ from each other; 10 or more mitochondria surrounding the axoneme (with a 9+2 microtubular pattern), arranged in two layers in the postnuclear cytoplasm and separated from the axoneme by the cytoplasmic canal. Two lateral fins on the same plane as the two central microtubules; doublets 3 and 8, which are ultrastructural characteristics of the sperma tail unlike other siluroids laking the lateral fins.

• Applied Microscopy
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• 제27권3호
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• pp.309-320
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• 1997

The spermatogenesis of korean leech, Whitmania edentula was observed, using both light and electron microscopes. The spermatogonium and maturing spermatozoon are connected with long cytoplasmic process to the cytophore, which supplys nutrition to the germ cells and supports synchronous maturity. The truck of korean leech is divided into three regions; a long ladder-shaped acrosome and head, long middle piece and long tail. Long head region twists to the dextral helix, and nuclei are surrounded with microtubules (manchette).The nebenkern formed with long mitochondrion exists in the middle pieces, and a long tail of Whitmania edentula ($9\times2+1$ axoneme) differs from the $9\times2+2$ axoneme of Rhynchobdellae. The late cytophore is mostly formed with crystalloid matter and a number of lysosomes, and matured spermatozooms are engulfed into the late cytophore.

• Applied Microscopy
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• 제15권2호
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• pp.80-88
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• 1985

The tentacular epithelial cells of Cipangopaludina chinensis were studied with electron microscope. The tentacular epithelium consists of columnar supporting cells, numerous glandular cells and ciliated cells. Glandular cells are classified into three types; type I (mucous metachromasia cell), type II(mucous goblet cell) and type III. Ciliated cells are subdivided into two types; type I ciliated cell has cilia with typical axoneme(9+2), and type II ciliated cell has cilia with unusual axoneme.

• Applied Microscopy
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• 제35권4호
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• pp.42-54
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• 2005

본 연구는 무당개구리과 (Discoglossidae)의 무당개구리(Bombina orientalis) 정자의 형태적 특징을 광학현미경과 주사 및 투과 전자현미경으로 관찰하였다. 정자두부는 전 후방의 끝이 뾰족하고 다소 유연성을 갖는 초생달 혹은 버들 잎 모양의 특이한 구조를 취하고 있었다. 핵은 전 후방이 가늘고, 중앙 부분은 굵은 원뿔형이었다. 염색질은 완전하게 농축되어 있지 않고, 마치 널빤지를 겹쳐 놓은 듯한 지붕모양과 같은 형태로 불규칙하게 배열되어져 있었다. 핵 내에는 불규칙한 형태의 nuclear lacunae들이 흩어져 있었다. 정자경부와 중편부는 발달 되어 있지 않았다. 편모는 9+2 구조의 axoneme, axial rod 그리고 undulating membrane을 가지고 있었다. 미토콘드리아들은 핵의 상단부를 둘러싸고 있는 protoplasmic bead내에만 국한되어 존재하고 있었다. 특히, 본 연구에서 핵의 전방부에서 중앙 부위로 주행하는 nuclear rod는 섬유성 다발로 구성되었으며, 마치 사람의 속눈썹 모양과 같은 형태를 취하며, 핵의 2/3까지 뻗쳐져 있었다.

• Applied Microscopy
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• 제31권3호
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• pp.223-233
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• 2001

우리나라 서해안에서 채집된 서해낙지(Octopus minor)의 정자 완성과정을 전자현미경을 통해 관찰한 결과 다음과 같았다. 서해낙지의 정자 완성 과정은 초기 중기 후기 정세포 그리고 성숙정자 등 4단계로 나눌 수 있었다. 초기 정세포는 구형의 세포로서 전자밀도가 낮아 밝게 보였으며 핵의 상단부 골지체로부터 형성된 첨체는 전자밀도가 높아서 어둡게 관찰되었다. 핵의 하단 근위 중심소체에서 유도된 것으로 보이는 extra-nuclear rod(enr)는 처음에는 구형에서 타원형으로 변모되면서 핵의 상단부위까지 신장되었으며, 원위중심소체로부터는 축삭이 형성되는 모습도 관찰되었다. 핵막 주위에서 많은 수의 미세소관으로 형성된 만췌트(manchette)도 관찰되었다. 중기 정세포는 핵내 염색질이 가는 실모양으로 응축 되었고, 이 시기에서도 만췌트가 핵막의 주위에서 관찰되었다. 특히 구형의 첨체는 긴 타원형으로 변모되면서 많은 수의 가로무늬를 형성하였고 전자밀도는 중등도로 나타났다. 후기 정세포는 핵내 염색질이 굵고 짧게 응축되었고, 중편에서는 미토콘드리아가 축삭을 감싸고 있는 mitochondrial sleeve를 형성하였다. 축삭은 전형적인 9+2 구조를 보였으며 축삭 주위에서는 9개의 금은 섬유(coarse fibres)도 관찰되었다. 성숙정자의 첨체 내강에서도 가로무늬가 관찰되었는데 특이하게도 가로무늬 사이에서 일정한 간격의 돌기물들이 관찰되었다. 성숙정자의 전체 길이는 약 $390{\mu}m$였으며 첨체는 나선형으로 꼬여 있었으나 머리부위는 꼬여 있지 않고 바나나 모양으로 약간 휘어져 있었다. 또한 정자의 중편에는 $11\sim12$개의 미토콘드리아가 굵은 섬유들을 둘러싸고 있었으며, 이 금은 섬유들은 꼬리의 주편 (main piece)까지만 연결되고 단편 (end piece)에서는 9+2구조의 축삭만이 관찰되었다.

• Applied Microscopy
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• 제28권1호
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• pp.39-48
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• 1998

동자개 정자는 구형의 두부와 짧은 중편 및 긴 편모를 가지고 있으며 비교적 그 구조가 단순하고 그 길이는 $76{\mu}m$이다. 대부분의 경골어류에서와 같이 첨체를 가지고 있지 않으며, $1.67{\mu}m$의 직경을 가진 핵에는 $1.0{\mu}m$ 정도로 깊이 함입된 핵와가 있고 그 속에 기부 및 말단 중심립이 들어있었다. 두 중심립은 서로 약 $160^{\circ}$의 각도로 배열되어 있으며, 말단부 중심립의 삼중미세소관과 핵 기부에 있는 축사의 이중미세소관 각각으로부터 부수체가 핵막을 항해 접선방향으로 배열되어 있었다. 약 20개 정도의 미토콘드리아가 중편 세포질에 2층 또는 3층으로 배열되어 있으며 축사와는 세포질관에 의해 분리되어 그 주위를 둘러싸고 있었다. 축사의 이중미세소관의 A소관에는 디네인 외완이 관찰되지 않았다. 한 쌍의 lateral fins는 중심미세소관의 축에 평행하게 측면으로 돌출되어 있는데 이것은 동자개 정자 꼬리의 특징으로서 다른 메기류에서는 보고되지 않았다.

• Applied Microscopy
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• 제26권2호
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• pp.221-233
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• 1996

In order to study process of spermiogenesis of the Korean manchurian field mouse, Apodemus spesiosus peninsulae, the testis obtained from sexually matured male reproductive organs, were examined with electron microscopy, and the following results were obtained based on the characters of cell differentiation. 1. According to the features of cell structure, spermiogenesis of the Apodemus spesiosus peninsulae was five phases: Golgi, cap, acrosome, maturation and spermiation phase. They were further subdivided into two steps of early and late phases respectively. Hence, the spermiogenesis consists of ten steps. 2. In the changes of the chromatin, the chromatin granules began to be condenced in the cap phase and regularizated at maturation phases, and a perfect nucleus of sperm was formed at the spermiation phases. 3. The formative period of sperm tail began to be develop in the early Golgi phase and completed at the spermiation phases 4. The outer dence fibers of middle piece were arranged in a horseshoe fashion. Nos. 1, 5, 6 and 9 of the outer dense fibers were larger than the others. The structure of axoneme in the middle piece was 9+2, and the axonemal complex consists of A and B microtubules, dynein arms and radial links.

• 한국패류학회지
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• 제24권1호
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• pp.1-10
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• 2008

Spermatogenesis and the reproductive cycle in male Spisula sachalinensis were investigated by cytological and histological observations. The morphology of the spermatozoon has a primitive type and is similar to those of other bivalves in that it contains a short midpiece with four mitochondria surrounding the centrioles. But spermatozoon of this species has not axial rod and satellite body in the midpiece. The morphologies of the sperm nucleus type and the acrosome shape of this species have a globe-shape type and modified cap-like shape, respectively. The spermatozoon is approximately $40-45{\mu}m$ in length including the sperm nucleus length (about $1.35{\mu}m$), acrosome length (about $1.50{\mu}m$) and tail flagellum. The axoneme of the sperm tail flagellum consists of nine pairs of microtubules at the periphery and a pair at the center. The axoneme of the sperm tail shows a 9+2 structure. The spawning period of these species lasts from June to July, and the main spawning occurs in July when seawater temperatures are greater than $20^{\circ}C$. The male reproductive cycle of this species can be categorized into five successive stages: early active stage (October to January), late active stage (February to April), ripe stage (April to June), partially spawned stage (June and July), and spent/inactive stage (August to September).