• Title/Summary/Keyword: dimorphism

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A New Genus and Two New Species of Copepoda(Poecilostomatoida, Sabelliphilidae) Associated with the Tubicolous Polychaetes in the Yellow Sea

  • Hoi, I-I
    • Animal cells and systems
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    • v.5 no.1
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    • pp.1-9
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    • 2001
  • Terebelliphilus simplex n. gen., n. sp. and Myxomolgus invulgus n. sp. are described from the tubicolous polychaetes found in the intertidal shores in the Yellow Sea. The new genus Terebelliphilus belongs to the family Sabelliphilidae but is characteristic in bearing the reduced segmentations In legs 1-4, an unusual sexual dimorphism in antennule, and the ventral location of genital areas. Myxomolgus invulgus is readily distinguishable from its congeners by the morphological features of rostrum, antennule, mandible, maxilla, leg 4 and female leg 5.

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Sexual dimorphism in morphometric characteristics of cocktail wrasse

  • Park, I.S.;Zhang, C.I.;Lee, Y.D.
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2003.05a
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    • pp.331-332
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    • 2003
  • Protogyny is known in 14 families of fishes, 11 of which inhabit coral reef areas. The wrasses (Labridae) comprise a large and well-known family of coral reef fishes that exhibit sequential hermaphroditism. The purpose of the present investigation was to examine the allomeoic growth patterns of several morphometric characteristics, including those used commonly to distinguish sexes of cocktail wrasse, pteragogus aurigarius (Richardson) and to assess their effectiveness in discriminating between males and females. (omitted)

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Morphological study of Oncorhynchus spp.(Pisces : Salmonidae) in Korea- III. Sexual dimorphism of chum salmon, Oncorhynchus keta. (한국산 연어속 어류의 형태학적 연구- III 연어, oncorhynchus keta의 성별 형태 차이)

  • Myoung, Jung-Goo;Hong, Kyung-Pyo;Kim, Yong-Uk
    • Korean Journal of Ichthyology
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    • v.5 no.1
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    • pp.85-95
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    • 1993
  • Sexual dimorphism of the matured chum salmon, Onchorhynchus keta, have been studied based on biometrical measurements and osteological characters. Male chum salmon has an elongated and hooked upper jaw and canine-like teeth on the upper and lower jaw. The ratios of snout length (SnL) and upper jaw length (UJ) to head length of male were larger than those of the female, whereas eye diameter (ED) and postorbital part of head (CK) of the male were smaller than those of the female's. The ratios of body depth, caudal peduncle depth, anal fin length and adipose fin length to the standard length (PBL) of the male were also larger than those of the female. On sexual dimolrphism was detected in number of fin rays, gill rakers and pyloric ceaca, where as number of lateral line scales and caudal vertebrae of the female was larger than those of the male. Glossohyal and vomer bones has no sexual difference. The ratio of width to length of supraethmoid bone of the male was larger than that of the female. The ratio of frontal part to posterior part of parasphenoid bone of the male was smaller than that of the female.

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Abundance and Breeding Migration of the Asian Toad (Bufo gargarizans)

  • Sung, Ha-Cheol;Park, Oan-Hee;Kim, Su-Kyung;Park, Dae-Sik;Park, Shi-Ryong
    • Journal of Ecology and Environment
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    • v.30 no.4
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    • pp.287-292
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    • 2007
  • We monitored a breeding population of the Asian toad (Bufo gargarizans), in the Wonheunge pond at Sannamdong, Chungju, from 5 March to 11 April, 2006 and 14 February to 31 March, 2007 to investigate their movement patterns, breeding population sizes, and physical characteristics. Terrestrial migration to the pond started on 5 March in 2006 and 14 February in 2007. We captured a total of 266 immigrating individuals (213 males, 53 females) in 2006 and 307 (222 males, 85 females) in 2007, and found 50 adults apparently killed by motor vehicles while migrating to the pond in 2007. Emigration from the pond to terrestrial sites started on 15 March 2006 and 5 March 2007. We captured a total of 245 emigrating toads (181 males, 65 females) in 2006 and 99 (92 males, 7 females) in 2007. An additional 10 emigrating adults were found dead on the road. During both the immigration and emigration periods, two peaks in capture frequency appeared for each sex in each breeding season. The immigration peaks corresponded with higher temperatures, while the emigration peaks corresponded with high humidity. Migrating Asian toads showed sexual size dimorphism and a male-biased sex ratio. Body weights and SVL (snout-vent length) of immigrating and emigrating individuals were negatively related with migration dates.

Disruption of the Dual Specificity Kinase Gene Causes the Reduction of Virulence in Candida albicans (이중특이성 인산화 효소의 결손이 Candida albicans 병원성에 미치는 효과)

  • Park, Yun-Hee;Park, Hee-Moon
    • The Korean Journal of Mycology
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    • v.39 no.1
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    • pp.85-87
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    • 2011
  • The opportunistic human pathogen Candida albicans has the ability to convert from yeast-form to pseudohyphal or true hyphal form. The morphological transition is considered as an important virulence factor, because the decrease or lack in dimorphism causes the reduction of virulence. Our previous study revealed that the disruption of dual specificity kinase gene caused the reduction of dimorphism in C. albicans. Therefore we tested the effect of dual specificity kinase in virulence using mouse model. The mean survival time for kinase-defective strains was about 15 days in comparison with those of wild-type, 3.9 days. Moreover the fungal burden on kidneys for kinase-defective strains was decreased by ten-fold than that for wild-type. These results suggest possible involvement of dual specificity kinase in a novel signal transduction pathway for morphological transition and virulence of C. albicans.

The Structures of Feeding Organs in Two Korean Ricefishes (Pisces, Adrianichthyidae), Oryzias latipes and O. sinensis (한국산 송사리속 Oryzias 2종 섭이기관의 구조적 특징)

  • Kim, Hyun-Tae;Kim, Jae-Goo;Park, Jong-Young
    • Korean Journal of Ichthyology
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    • v.24 no.4
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    • pp.247-252
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    • 2012
  • Structure on the feeding organs in two Korean ricefishes, Oryzias latipes and O. sinensis, was examined in the jaws and the teeth. In the jaw, O. latipes has a dent on the dorsal edge of distal arm of premaxilla (vs. straight in O. sinensis) and a alveolar arm of premaxilla running in straight line with distal arm of premaxilla (vs. ventra line in O. sinensis). O. latipes has also a dent on the posterior edge of dentary which is connected to coronoid process of dentary (vs. straight in O. sinensis). Large teeth developing only in the male, which is sexual dimorphism, developed into outside direction of the mandible in O. latipes (vs. dorsal direction in O. sinensis). In the teeth forms, O. latipes has two types (conical type and arrowhead type), whereas O. sinensis has only one type (conical type). Through this study, we confirmed that two Korean ricefishes show distinctive characteristics in the structure of the feeding organs.

Sexual Dimorphism and Secondary Sexual Characters of Acheilognathus signifer (Cyprinidae: Acheilognathinae) (묵납자루, Acheilognathus signifer (Cyprinidae: Acheilognathinae)의 성적 이형과 이차 성징)

  • Baek, Hyeon-Min;Song, Ho-Bok
    • Korean Journal of Ichthyology
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    • v.18 no.2
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    • pp.141-147
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    • 2006
  • The matured female and male of A. signifer differed in external morphology and body color. There were significant differences in PAD, PAB, PMP and PQR between matured female and male. Green color was very widely distributed in whole as nuptial color, that is similar to green and cyan color in the body part, yellow color in the ventral part and red and yellow color in the tail part. The nuptial organ of A. signifer was formed in a cluster on the horny substance of both sides above the mouth. There were 25~30 nuptial organs in a side. The nuptial organs disappeared with crumbling down from middle part of nuptial organ after spawning period. The nuptial organs disappeared mostly in September as non spawning period and a part of the nuptial organs remained as a vestige in the edges of both sides.

Effect of Low Temperature Pretreatment on Pollen Dimorphism and Embryo Formation in Anther Culture of Platycodon grandiflorum (도라지 (Platycodon grandiflorum) 약배양에서 저온처리가 화분 2형현상 및 배형성에 미치는 영향)

  • 고정애
    • Korean Journal of Plant Tissue Culture
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    • v.26 no.3
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    • pp.149-156
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    • 1999
  • In order to investigate the effect of low temperature pretreatment on pollen dimorphism and embryo formation in anther culture of Platycodon grandiflorum, the anthers with microspore at the uninucleate stage were cultured on Murashige and Skoog medium supplemented with 0.5mg/L NAA and 1.0 mg/L BA. The low temperature pretreatment have clear effect on the frequencies of S pollen grains, symmetrical binucleate microspores (B type of S pollen), multinucleate and multicelled pollen grains. Especially, after low temperature pretreatment at 8$^{\circ}C$ for 5 days increased the frequency of S pollen grain (20.6%) in vivo. In addition, the highest frequency of callus induction (54.9%) and embryo formation (9.9%) were obtained from the anther pretreatment at 8$^{\circ}C$ or 5 days. Three distinct pathways could be recognized in the androgenesis, one involving mainly the vegetative cell, the second starting with the vegetative and the generative cell, respectively, and the third accompaning with two equal vegetative type cells in the pollen grains.

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Molecular Sexing and Species Identification of the Processed Meat and Sausages of Horse, Cattle and Pig

  • Kim, Yoo-Kyung;Kang, Yong-Jun;Kang, Geun-Ho;Seong, Pil-Nam;Kim, Jin-Hyoung;Park, Beom-Young;Cho, Sang-Rae;Jeong, Dong Kee;Oh, Hong-Shik;Cho, In-Cheol;Han, Sang-Hyun
    • Journal of Embryo Transfer
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    • v.31 no.1
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    • pp.61-64
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    • 2016
  • We developed a polymerase chain reaction (PCR)-based molecular method for sexing and identification using sexual dimorphism between the Zinc Finger-X and -Y (ZFX-ZFY) gene and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) for mitochondrial DNA (mtDNA) cytochrome B (CYTB) gene in meat pieces and commercial sausages from animals of different origins. Sexual dimorphism based on the presence or absence of SINE-like sequence between ZFX and ZFY genes showed distinguishable band patterns between male and female DNA samples and were easily detected by PCR analyses. Male DNA had two PCR products appearing as distinct two bands (ZFX and ZFY), and female DNA had a single band (ZFX). Molecular identification was carried out using PCR-RFLP of CYTB gene, and showed clear species classification results. The results yielded identical information on the sexes and the species of the meat samples collected from providers without any records. The analyses for DNA isolated from commercial sausage showed that pig was the major source but several sausages originated from chicken and Atlantic cod. Applying this PCR-based molecular method was useful and yielded clear sex information and identified the species of various tissue samples originating from livestock.