• The Korean Journal of Zoology
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• v.25 no.3
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• pp.107-114
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• 1982

A combination of ultraviolet irradiation and egg rotation was applied to Korean frogs to study the mechanisms of the establishment of the dorsal-ventral polarity. Rotation of the uncleaved egg was capable of preventing the characteristic syndromes associated with UV irradiation. As well, brief rotation of the egg before cleavage relocates the site of dorsal lip to a novel location in the embryo at gastrula stage. That is, the dorsal lip appeared on the opposite side to gravity at the rotation of the egg. Above results were discussed with the informations obtained from other anuran and urodele species, and were interpreted in terms of regulating mechanisms for early embryogenesis.

• The Korean Journal of Zoology
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• v.17 no.4
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• pp.159-162
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• 1974

Serum protein and hemoglobin patterns were obtained by cellulose acetate electrophoresis for several anurans. Differences were found both in the number of components from individual animal hemoglobins and in the mobility of these components. Under the conditions employed, toad and R. plancyichosenica had a single component. Other frogs showed 2-component pattern. Sera of all anurans examined contain albumin but no preablumin. Relatively few assayable proteins are found in serum from B. buro gragraizans and differ thereby from most serum patterns examined for frogs, which show complex serum protein bands. Different species have dissimilar patterns although some of bands are apparently homologous between species.

• The Korean Journal of Zoology
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• v.16 no.3
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• pp.171-176
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• 1973

Metaphases were obtained from the bone marrow cells of B. kangii Yoon, by means of direct air-drying technique. The karylogical characteristics of this species were as follows; 1) The diploid chromosome number was 22(2n=22) which might be divided into six large and five small homololgous chromosmes. 2) All homologous chromosomes of this species were metacentrics. 3) The secondary constriction was not found in all members of chromosomes. 4) There was no evidence for the existence of a specific sex chromosome pair in this species.

• Applied Microscopy
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• v.39 no.2
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• pp.107-115
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• 2009

The programed cell death of the cutaneous epithelial tissue during tail regression stages in anuran tadpoles of the blackspotted frog, Rana nigromaculata were visualized by the histochemical and transmission electron microscopic techniques. Metamorphotic changes in the tail regression during the period of the Shumway stage number 31 to 33 are characterized by the disappearance of mucous layer and formation of compound epithelium through cutaneous thickening. Following the TUNEL (terminal deoxynucleotidyl transferase-mediated biotinylated d-uridine triphosphate nick end labeling) staining technique, the apoptotic cells were detected at the distal region of the tail skin initially, but they can be seen at the proximal region according to their following development. It has been also revealed that the number of the TUNEL-positive cells gradually increased from apical to basal direction of the epithelial layers during the tail regressing stages. Following the TEM observation, the early apoptotic cells shown in the epithelium demonstrated condensation and margination of the chromatin material at the nuclear periphery. Another epithelial apoptotic cells were shown nuclear fragmentation, membrane blebbing and cytoplasmic condensation. Following the process of the apoptotic degradation, well preserved organelles and nuclear fragments can be identified in the cytoplasm of lysosome-rich cells, however they soon reduced to lysosomal residual bodies through the progressive degradation.

• Animal Systematics, Evolution and Diversity
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• v.12 no.3
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• pp.253-264
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• 1996

The ultrastructure of spermatozoa in urodeles and primitive anurans was examined and compared. The spermatozoa of urodeles are characterized by seven plesiomorphies in subacrosomal cone, endounclear canal. perforatorium, ring, marginal filament, undulating membrane and tail axis. Most primitive anuran spermatozoa have no marginal filament, subacrosomal cone and ring structure with the exception of having the subacrosomal cone in Ascaphus and the ring in Discohlossus as compared with those of urodeles. Persistence of the subacrosomal cone and the ring structure is typical in most urodeles and is further linked with the primitive anurans. Therefore, these characters are regarded as symplesiomorphies in urodeles and primitive anurans. The organization of sperm tail, endounclear canal and perforatorium indicates a close phylogenetic relationship between urodeles and the primitives anurans.

• Animal cells and systems
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• v.4 no.1
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• pp.95-100
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• 2000

The regional distribution and relative frequencies of endocrine cells were studied immunogistochemically (PAP methods) in the alimentary tract of the tree frog, Hyla areorea japonica, using specific antisera against serotonin, somatostatin, bovine Sp-1/chromogranin (BCG), cholecystokinin (CCK)-8, vasoactive intestinal polypeptide (VIP), gastrin, bombesin, secretin and pancreatic polypeptide (PP). Six kinds of endocrine cells were identified in this study, These immunoreactive cells were located in the gastric glands of stomach regions and in the basal portion of the epithelium of the intestinal tract or esophagus with variable frequencies. They were spherical or spindle-shaped. Serotonin-immunoreactive cells were observed in the whole alimentary tract including the esophagus. Somatostatin-immunoreactive cells were also detected throughout the alimentary tract except the rectum. CCK-8-immunoreactive cells were observed from the pylorus to ileum. Vip-immunoreactive cells were restricted to the rectum. Bombesin-immunoreactive cells were restricted to the fundic gastric regions and gastrin-immunoreactive cells were restricted to the pylorus. However, no BCG-, secretin and PP-immunoreactive cells were demonstrated in this study. In conclusion, the regional distribution and relative frequency of the endocrine cells in the alimentary tract of the tree frog were similar to other anuran species, but some differences which may be caused by feeding habits and species specification were also observed.

• The Korean Journal of Zoology
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• v.27 no.2
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• pp.93-102
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• 1984

Xenopus laevis eggs were de-jellied and manually manipulated to remove their vitelline membranes. They were then positioned in a variety of orientations re. gravity. That is the future ventral side was located upwards (opposed gravity) or downwards (faced gravity). Development through the tailbud stage was observed and the frequency of double axes formation recorded. Orientation of the egg re. its natural polarity was not an important factor in generating double axes. Its physical structure (flattened re. spherical), however, appeared to be important in determining the frequency of twinning. These observations give insights into the mechsnism of polarity establishment in anuran eggs, and provide methods which should be useful for studies on primary embryonic induction.

• Animal cells and systems
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• v.16 no.3
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• pp.260-267
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• 2012

Calling behavior is often used to infer breeding patterns in anurans. We studied the seasonal and diel calling activities of anuran species in a wetland in central Korea to determine the calling season and to evaluate the effects of abiotic factors on male calling. Acoustic monitoring was used in which frog calls were recorded for a full day, once a week, throughout an entire year. Using acoustic monitoring, we identified three frog species in the study site. Males of Rana dybowskii called in late winter and early spring; we thus classified this species as a winter/spring caller. The results of binary logistic regression showed that temperature, relative humidity, and 1-day lag rainfall were significant factors for male calling in R. dybowskii. Temperature and relative humidity were important factors for the calling activity of R. nigromaculata, whereas 24-h rainfall and 1-day lag rainfall were not significant. Thus, we determined R. nigromaculata to be a summer caller independent of weather. In Hyla japonica, relative humidity, 24-h rainfall, and 1- day lag rainfall were significant for male calling, suggesting that this species is a summer caller dependent on local rain.

• Korean Journal of Ecology and Environment
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• v.52 no.4
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• pp.358-365
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• 2019

We measured the body composition, including bone mineral density (BMD) and food resource availability using dual energy X-ray absorptiometry and the carbon and nitrogen stable isotope ratios of body condition of 4 anuran species(Hyla japonica, Glandirana rugosa, Pelophylax nigromaculatus, Lithobates catesbeianus) in South Korea. Additionally, the carbon and nitrogen stable isotope ratios were employed to determine the food resource availability of anurans. We figured out the relationship between the body composition, including BMDs and food resource availability. The body composition and BMDs did not differ between male and female while there was difference among the species. Food resource availability and BMDs were the highest in L. catesbeianus, the lowest in H. japonica. BMDs tended to increase with higher food resource availability. Body composition and BMDs, which represent the body condition of an individual, can be used as an ecological indicator to assess the stability of the habitat of anurans.

• Animal cells and systems
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• v.2 no.4
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• pp.477-481
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• 1998

Previous studies have postulated that isometric animals exert similar locomotory capacity (speed, distance) because the amount of energy available for the motion would be the same regardless of body mass (m). To test propriety of this theory, we examined body shape and take-off potential of two frog species, Rana nigromaculata (powerful jumpers) and Bombina orientalis (slow hoppers). Morphological measurements included thigh muscle mass (indicative of total muscle force), hindlimb length (L, determining acceleration distance), and interilial width (shaping take-off motion). To gauge locomotory capacity, take-off speed (v) and take-off angle ($\theta$) were measured from video analyses, and jump distance (R) and take-off Power ($P_{t}$ ) were calculated from equations $R=V^{2}sin2\theta/g$ and ($P_{t}$＝$㎷^{3}/2L$(where g is the gravitational constant). Scaling exponents of morphometric variables for both species were 0.96-1.11 for thigh muscle mass, 0.28-0.29 for hindlimb length, and 0.30-0.36 for interilial width. Scaling exponents of locomotory performance for the two species were -0.01-0.14 for take-off speed, 0.24-0.31 for jump distance, and 0.66-0.84 for take-off power. The results demonstrate that the frogs of this study showed isometric body shape within species, but that take-off response changed allometrically with body mass, indicating that these data did not fully support the previous proposition. An exception was found in take-off speed of B. orientalis, in which the speed changed little with body mass (slope＝-0.01). These findings suggest that the energy availability approach did not properly explain the apparent allometric relations of the take-off response in these animals and that an alternative model such as a power production approach may be worth addressing.