• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.60-60
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• 2003

릿테르개멍게는 척색동물문 해초강에 속하는 멍게류로서 고착생활을 하며, 보통 해조류나 히드라 등으로 덮여 있어 눈으로 식별하기가 어렵고, 생태 및 분류에 관한 연구만이 있을 뿐이다. 이 연구는 제주도 연안에 서식하는 릿테르개멍게의 번식생태에 대한 기초자료를 얻고자 배우자형성과정 및 생식소 발달 단계 등을 조직학적으로 조사하였다. 실험 재료는 제주도 용담 연안에서 2001년 11월부터 2003년 1월까지 매월 20개체씩 총 300개체를 채집하여 생식소의 조직학적 변화를 관찰하였다. 릿테르개멍게는 자웅동체로서 생식소는 체벽부에 붙어 있고, 성숙시기에 난소는 적색을, 정소는 유백색을 띠고 있다. 생식소와 체벽부를 포함해 절단된 조직표본에서 보면 외측체벽은 근섬유를 포함한 섬유성결합조직이 발달해 있고 여기에 이어진 방형의 난소낭과 그 주변부에 자리 잡고 있는 여러 개의 정소낭을 식별할 수 있었다. 생식소 발달 및 배우자형성과정, 월별 생식소변화를 토대로 생식주기를 구분하면 성장기 (3-5월),난황기 (5-7월), 성숙기 (7-11월), 방출기 (11-2월), 회복기 (1-3월)로 구분되었으며, 주 산란시기는 11-1월로, 연중 1회의 산란시기를 갖는다.

• MALSORI
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• no.43
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• pp.11-23
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• 2002

In this paper, speech style is divided into two - read speech and dialogue. In the experiment, read speech and dialogue use the same sentence to control discrepancy from different sentence. While the number of AP in read speech is less than in dialogue, the number of IP in read speech is more than in dialogue. The number of syllables which consist of AP is more various in dialogue. Intonational patterns of the first AP in IP make a difference. In dialogue, there is a pattern which has many high tones - LHH. The FO range in dialogue is wider than in read speech.

• The Korean Journal of Malacology
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• v.23 no.1
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• pp.39-49
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• 2007

We investigated to understand the differences in the karyotypes and the reproductive characteristics between the diploid clam, Corbicula japonica in the brackish water and the triploid clam, C. fluminea in the freshwater. The number of chromosomes of the diploid C. japonica were 38, which can be grouped into 19 pairs of two homologues. These can be divided into 11 pairs of telocentric, 4 pairs of subtelocentric, 3 pairs of submetacentric and one pair of metacentric chromosomes. C. japonica is oviparous and dioecious. The clam has two pairs of gills, with the inner and outer-demibranchs, however, they do not act mainly as marsupia. External fertilization occurs in the brackish water. The triploid marsh clam, C. fluminea has 54 chromosomes, which can be grouped into 18 sets of three homologues. These 18 sets can be divided into one metacentric group, five submetacentric groups and 12 subtelo- or telocentric groups. C. fluminea is ovoviviparous and functional hermaphrodite. The triploid condition may be closely related to hermaphroditism. This species has the inner-demibranchs acting mainly as marsupia. The depletion of ripe eggs occurred in the inner-demibranchs of the gill during the incubatory periods, and ripe eggs produced in the hermaphroditic follicles in the gonad during the non-incubatory periods. The gonad developmental stages of two marsh clams (C. japonica and C. fluminea) can be divided into five stages: early active stage, late active stage, ripe stage, partially spawned stages, and spent/inactive stage.

• The Korean Journal of Malacology
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• v.11 no.2
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• pp.123-134
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• 1995

한국산 산민달팽이 (Incilaria fruhstorferi)의 자성 생식기관을 조직화학적 방법을 이용, 광학현미경으로 관찰한 결과는 다음과 같다. 알부민선(albumen gland)은 대자웅동체관 위에 있으며, 산성 점액다당류와 중성 점액다당류 그리고 단백질성 분비물을 형성하는 세포들로 구성되어 있었다. 수정실(fertilization chamber)을 구성하는 내강 상피는 불규칙한 단층섬모원주상피와 위중층섬모원주상피세포가 3대 1의 비율로 구성되어 있으며, 결합조직에서 형성된 산성점액다다류성 과립들이 상피세포를 거쳐 내강 속으로 분비되었다. 또한 수정실의 외측표면은 기능은 알 수 없으나 산성 점액다당류를 분비하는 대형 세포들로 둘러싸여 있었다 . 수란관(oviduct)의 내강은 크로 작은 돌기로 인해 별모양을 나타내었다. 내강은 위중층원주상피세포로 구성되었으며 그들 사이에서 분비세포의 존재는 확인되지 않았다.질(vagina)의내강은 덮은 세포는 해면조직 형태의 세포와 단층섬모원주상피세포 그리고 위중층섬모원주상피세포 등 다양한 종류로 구성되어 있었으며, 잘 발달된 두터운 근육층은 질의 신축성을 높여 주었다. 정자낭(spermatheca)은 그 형태와 크기, 색깔 등이 종에 따라 다양하고, 질과 연결되는 자성생식기관으로 알려져 있다.

• The Korean Journal of Malacology
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• v.13 no.1
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• pp.55-64
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• 1997

꼬막, Tegillarca granosa은 우리나라 남해 및 서해안 일대에서 서식하는 중요한 수산자원 중의 하나이지만, 이에 대한 생물학적 기초연구는 거의 없는 실정이다. 따라서 1995년 2월부터 1996년 1월까지 전남 벌교연안에서 채집한 꼬막의 생식소발달, 생식세포형성과정 및 생식주기를 조사하였다. 1. 꼬막은 자웅이체이면서 난생이고, 생식소는 내장낭의 간중장선을 싸고 있는 결합조직으로부터 족부의 근육층까지 분포한다.2. 미분화간층직과 호산성 과립세포들이 초기 활성기의 소낭에 풍부하게 나타나기 시작하여 완숙기에는 거의 없어지는 것으로 보아, 이들은 생식소 및 생식세포형성과 발달에 영향을 공급하는 영향세포로 생각된다.3. 생식소발달, 생식세포형성과정, 조직분화과정 및 세포학적 특성에 따라, 이들의 생식주기를 초기 활성기, 완숙기, 부분 방출기, 방출 및 비활성기 등으로 구분할 수 있다. 4. 방란 및 방정은 수온 2$0^{\circ}C$정도되는 6월하순부터 시작되고, 주산란시기는 수온이 23-24$^{\circ}C$정도 되는 7-8월이며, 완숙란의 크기는 50-60$\mu\textrm{m}$이다.5. 비활성기는 9월에서 이듬해 4월까지 지속되는 비교적 긴 기간이며, 초기 활성기도 비교적 길어 1월에서 5월까지 지속되는 반면, 후기활성, 완숙 및 방출기는 비교적 짧아, 5월에서 8월까지 모두 완료된다.6. 비만도의 월별 변화는 생식소의 발달, 생식주기 및 수온과 밀접한 관계가 있다.7. 사용된 재료 433개체 중 1개체가 자웅동체현상을 나타내었다.

• The Korean Journal of Malacology
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• v.30 no.2
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• pp.107-116
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• 2014

Gonadal development and maturation mechanism were studied on the freshwater marsh clam Corbicula papyracea (Heude), which is the endangered species in Korea. The specimens were collected in the rearing ponds and waterway of NFRDI in Gapyeong-gun, Gyeonggi-do from January to December 2004, and then investigated by condition factor, relative growth, gonadal development phases and gonad histological characters based on 30-50 individuals every month. Comparing with the freshwater marsh clam, C. papyracea is small, light olive brown shell and violet interior. The hermaphrodite individuals of C. papyracea take an internal fertilization and fertilized eggs are stored in the foster-sack in the gills, then the hatched juveniles are released outside after an ovoviviparous process. The average water temperature of inhabit area was in range of $1.8-27.0^{\circ}C$ and usually took great effects on the gonad maturation of C. papyracea. The condition factor ranged from 0.14 to 0.21 throughout the year, which was the lowest during winter season (December-February), and gradually increased to the highest value of 0.21 in May. The ratio of meat weight to total weight was 25.9-38.7%, indicating the similar trend with condition factor. The highest values of condition factor and the ratio of meat weight appeared 1-2 months later than gonadosomatic index reached the peak value, it was probably because that the ovoviviparous eggs would spend a long period before hatching from the foster-sack in the gills. To synthesize the characters of meat weight, condition factor and gonad development by histological study, reproductive cycle of C. papyracea could be divided into five successive stages: multiplicative stage (December to February), growing stage (February to May), mature stage (June to August), spawning stage (August to November), recovery stage (November to December). The smallest shell length of matured C. papyracea was 12.6 mm, and individuals, larger than 16 mm, was formed the nursery in the gills.

• The Korean Journal of Malacology
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• v.18 no.2
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• pp.67-76
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• 2002

Gametogenesis, reproductive cycle, egg diameter composition and gonad index of the black-lined limpet, Cellana nigrolineata, were histologically examined. Specimens collected from the rocky intertidal zone of Hamdeok, Jeju from July 1997 to June 1998. The black-lined limpet has an unpaired gonad located at the ventro-anterior part, underneath the visceral mass. The gonad index increased from May when water temperature increased and reached maximum in August. It began to decrease from September thereafter, maintain a low value from January to April. The following reproductive cycle were classified based on the monthly changes of the histological features and sizes of oocytes in the gonad: recovery stage (November to April), active stage (March to June), ripe stage (May to October), spent stage (August to December). Spawning occur once a year between September and October. The black-lined limpet appeared to be gonochorism, neither sex change nor hermaphroditie.

• Development and Reproduction
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• v.5 no.2
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• pp.137-144
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• 2001

Gametogenesis and gonadal development of the sea squirt Halocythia roretzi, which is two years old were investigated by histological study. The specimens were collected in Guryong-po coastal area Kyoungsangbuk-do, Korea from May 1996 to April 1997. The sea squirt is hermaphrodite and oviparous. The ovary is located in the inner wall of the tunic year-round, but the testis can be distinguished from in June. The ovary is composed of 6∼8 gonoducts at the left side and 8∼10 ones at the right side, the testis consists of the complex gonad having irregular sacular structures. Oogonia in the ovarian sac were 11.7∼15.6 ${\mu}m$ in diameter. The early developing oocytes were 39.6∼47.6 ${\mu}m$ and nucleus 10.0∼25.0 ${\mu}m$ in diameter. Oocytes in the ovarian sacs during vitellogenesis were 158.6∼210.0 ${\mu}m$, and fully ripe oocytes which were to 210.0∼230.9 ${\mu}m$ in diameter had several test cells in the cortical parts showing a characteristic of vertebrate. The testis showed a general spermatogenesis as in the marine animals. The three-year old sea squirt occurred the first spawning between January to February under 10$^{\circ}C$