• 환경생물
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• 제23권2호
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• pp.129-134
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• 2005

포란한 성충 암컷 Tigriopus japonicus(요각류)를 내분비계 교란물질로 잘 알려져 있는 4-nonylphenol에 노출하여 생존율과 포란율의 변화를 살펴보았다. 실험생물은 2004년 4월 제주도 구안연안에서 플랑크톤망으로 쓸어 잡기로 채집한 후 실내순응을 한 달 동안 시켰다 치사율은 노출농도의 높아지면 증가하였으나 그 경향이 뚜렷하지 않았다. 반면, 노출 후 처음으로 치사한 개체가 발생하는 시기는 비처리군과 처리군에 따라 명백한 차이를 보였다. 포란한 암컷을 실험조건에 이동시키면 생리적인 변동으로 인해 알이 떨어졌다가 $4\~5$일 후 비처리군은 $100\%$ 포란을 회복하지만 처리 군에서는 $89\~95\%$가 회복되어 약제노출에 따른 영향을 보였다. 치사가 발생하는 시기는 비처리 시에는 10일 후부터이지만 노출 시에는 4에서 6일 후부터 발생하였다.

• Journal of Plant Biology
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• 제6권2호
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• pp.3-6
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• 1963

As a part of embryological studies of Panax ginseng, megasporangium and megagametophyte formations were investigated. Ovule is found to be auatropous. Small-sized nucellus is surrounded by thick layered single integument. As the embryo sac develops, the nucellus along with some parts of the inner epidermis of integument disintegrates and completely disappers at flowering stage. Embryo sac takes the type of typical Polygonum although antipodal cells disappear and polar nuclei fuse to form secondary nucleus before fertilization. Mature embryo sac consists of egg apparatus and large secondary nucleus lying adjacent to the egg. Besides the normal ovule, tiny incomplete ovule develops near the base of style. Frequently two normal ovules are formed in a single locule. Chromosome number counted is PMC is n=24.

• Applied Microscopy
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• 제28권3호
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• pp.273-282
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• 1998

Ultrastructure of fertilized egg envelope in the tomato clown anemonefish (Amphiprion freatus) was examined by mean of light, scanning and transmission electron microscopies. The fertilized egg of tomato clown anemonefish was of non-transparent, ellipsoidal, adhesive and non-floted type, and there were numerous oil droplets in the yolk sac and adhesive filaments in the area of the animal pole. The outer surface of egg envelope was smooth. The fertilized egg envelope consisted of two distinct layers; a non-adhesive outer electron-dense layer and an inner layer, consisting of five horizontal low electron-dense lamellae alternating with the middle electron dense interlamellae.

• 한국발생생물학회지:발생과생식
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• 제1권1호
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• pp.91-97
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• 1997

In order to study the reproductive physiology of Sand ell(Hypoptichus dybowskii) catched at kangwon-do, Wooamjin Bay, spawning and egg development were investigated in April and May, 1996. The observed spawning period was from the middle of April to the end of May with the water temperature above $8^{\circ}$C. Body size and colouration were distinguished between male and female. The type of testicular structure is lobular, and the ovary is a pair of sac-sahaped covering with a fibromuscula capsule and comprising a mature egg of average 86. The unfertilzed egg are demersal and adhesive, and their diameter were 1.65-1.95 mm. the colour of yolk is light yellow and contained a lot of tiny oil globules. The average spawned egg was 62 in sargasso weeds. Hatching was observed in 12 days after fertilization with the water temperature of 14 ${\pm}1^{\circ}$C. The average size of larva after hatching was 6.85${\pm}$0.23mm in total length, and larva were containing yolk including globule.

• 한국응용곤충학회지
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• 제33권2호
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• pp.114-121
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• 1994

우리나라 남부지역 해송림에 피해를 주고 잇는 솔껍질깍지벌레으 해송 단목당 밀도가 추정되었다. 구피해자와 신규발생자에서 흉고직경 10cm내외의 공시목을 채취, 가해 약충의 서식가능 면적을 조사한 바 1차측지 밀도는 차이가 없었으나 2차측지 이하 부속지의 밀도는 구피해지가 낮았다. 약충의 분포양식은 양 지역의 고시목에서 유사한 형태를 나타냇으며 단목당 약충 추정수는 주간의 약충수에 비하야 구피해지에서는 10.8배 신규발생지에서는 13.1배로서 최소 4,200마리, 최대 208,500마리이었다. 오차범위 20%내에서 필요한 공시지의 수는 수관중분의 내부, 수관하부의 중부 및 내부에서 채취한 길이가 10~20cm, 20~30cn인 2차측지이하 부속지로서 각 21개 및 11개이었다. 알주머니는 단목당 63.6%가 주간에 분포하여 이중 가장 밀도가 높은 부위는 역지를 보유한 절간마디이었으며 이를 포함, 인접된 4개 절간에서의 밀도는 주간 전체 밀도의 약 37%이었다.

• The Korean Journal of Ecology
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• 제19권5호
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• pp.477-486
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• 1996

The freshwater goby, Micropercops swinhonis ($G\"{u}nther$) was studied on the spawning behavior and egg develeopment at the two areas of Chollabukdo, Korea from March to May 1995. Egg mass attached to a layer under stones and the inner wall of waterplant, Cyperus. Spawning behavior was divided in to 1) premating stage: selecting spawning sites and formation of territory by male, 2) mating stage: enticement with zigzag-like dance and intermittant shaking of head by male and fertilization, 3) postmating stage: fanning, guarding and cleaning the nest by male. The eggs were transparent and spherical in shape, measuring $0.9\times1.4mm$ with yellowish yolk sac and many oil globules. Hatching began in about ten days after fertilization at water temperature $16~20^{\circ}C$. The newly hatched larvae were 3.8~4.0 mm in total length with 30 myomeres and their mouths and anuses were opened. Melanophores appeared at the air-bladder and the ventral side of caudal region.gion.

• 한국수산과학회지
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• 제56권5호
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• pp.676-683
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• 2023

The development of the egg, larvae, and juveniles of Acheilognathus macropterus from the Wicheon stream of Nakdonggang River was investigated for early life history characteristics. The fish used in the study were collected from Wicheon stream located in Bian-myeon, Uiseong-gun, Gyeongsangbuk-do. The fertilized egg was 1.88±0.09 mm (n=30) in long diameter and 1.34±0.06 mm (n=30) in short diameter. After fertilization at a water temperature of 20℃, the egg took 31 h and 40 min to hatch. Newly hatched larvae had an average total length of 3.92±0.13 mm (n=30) and possessed a yolk sac the mouth and anus were not developed. Twenty days after hatching, the postflexion larvae had an average total length of 8.08±0.29 mm (n=30), with the tail tip fully bent at 45° and began feeding. Thirty-three days after hatching, the number of fin stems reached an integer with an average total length of 15.0±1.08 mm (n=30). In this study, differences in the egg size, hatching time, melanophore development period, and distribution location were confirmed between A. macropterus and allied species.

• 대한의생명과학회지
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• 제10권4호
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• pp.397-401
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• 2004

We have examined congenital malformation in developing chick embryo caused by endocrine disruptor, bisphenol A (BPA). We injected BPA into the air sac of developing egg on day 4 of incubation. BPA-treated group with a concentration of 10 ㎍/egg showed a little decrease on their body length compared to the untreated group. But the group treated with 50㎍/egg revealed severe malformation in eyeballs and bills. The group treated with 100㎍/egg could not continue their development after few days of incubation. These results indicate that BPA clearly inhibits the normal development in chick and it should be toxic to the developing fetus at early stage and in various tissues. The study should contribute to the understanding of toxic effect of BPA in developing human fetus when exposed to the BPA.

• The Korean Journal of Ecology
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• 제28권4호
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• pp.193-198
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• 2005

This study investigated the characteristics of the eggs and yolk sac larvae of Korean striped bitterling, Acheilognathus yamatsutae, spawned and grown In mussels. The number of eggs in the ovary was small ($358{\pm}108$ SD). The eggs were oval and large, and the formation of the perivitelline space was narrow. The eggs were hatched at only 41 hours after fertilization but the hatched larvae were underdeveloped. The development of yolk projection and minute tubercles on the skin surface was notable, along with the vividly moving tail in the hatched larvae. The yolk projection and minute tubercles were disappeared upon enhancement of the motor ability of the larvae was enhanced. The formation of eyes and body pigments of the larvae was relatively delayed in comparison with that of other cyprinid larvae. After completely consuming the yolks the larvae escaped from the mussel for free swimming and exogenous feeding.

• Applied Microscopy
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• 제32권1호
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• pp.39-44
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• 2002

한국어류의 수정란 난막 미세구조를 분류체계에 따른 체계화 작업의 일환으로 난문의 유무, 난막의 표면 및 단면구조를 밝힘으로써 계통분류학적 기초자료를 제시하고자 경골어류, 구굴무치과에 속하는 얼룩동사리의 수정란을 실험재료로 하여 주사전자현미경과 투과전자현미경을 이용하여 관찰하였다. 수정란은 부착성 및 침성란으로 장타원형이었으며 동물극쪽에 부착사가 부착되어 있었다. 난황낭 내에는 많은 유적들이 있었으며, 난막 표면은 pore cannal들이 분포하고, 난문은 관찰되지 않았다. 난막은 두 층으로 구성되어 있었는데 외층은 전자밀도가 높은 비부착성이었으며, 내층은 전자밀도가 서로 다른 7층으로 구성되어 있었다. 이상과 같이 얼룩동사리 수정란 난막의 미세구조적 특징은 얼룩동사리의 수정란이 가지는 독특한 형태학적 형질로서 종을 분류하는데 사용될 수 있을 것으로 사료된다.