• Title/Summary/Keyword: biology contents

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A Comparative Study on the Curriculum of Biology in High School of Korea and the United States (한국과 미국의 고등학교 생물과 교육과청에 대한 비교 연구)

  • Moon, Doo-Ho
    • Journal of The Korean Association For Science Education
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    • v.10 no.1
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    • pp.17-31
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    • 1990
  • The purpose of this study is to make a comparative analysis of the educational bojective, organization, contents, teaching and evaluation of the biological curriculum in high school of Korea and the United States. The results are summarized as follows: 1. In case of the educational objectives, both Korea and the United States emphasize the importance of the process of inquiry, experimentation and observation. Particularily, great emphasis is placed upon the human centered curriculum by reinforcing the relationships between the nature and human being. 2. In regard to the educational organization, eleven credit units(Science I: 5 credits, Biology: 6 credits) is allocated in Korea, and ten credit unit, in the United States. Both of Korea and United Stats designate the biology as elective course. But the science I course is designated as required in Korea 3. This study have been analyzed the educational contents of the two countries within the framwork of the basic concepts and essential informations contained in the curriculum. Results of the analysis as follow: The educational contents have less quantity and lower level in Korea than in the United States. And interrelations among the other curricula are not well considered in the curriculum of Korea/ On the other hands, interrelations among the oter curricula are fully considered and the purpose for emphasizing the importance of the process of inquiry course is well considered in the United States. The themes are stressed on "Structure and Function" (34.5%), "Genetic continuty" (21.3%), "Diversity and Unit" (14.2%) and "Regulation and Homeostasis" (10.3%) in Korea, and in the United States "Structure and Function" (27.3%), "Diversity and Unity" (25.6%), "Genetic continuty" (17.9%) and "Organism and Environment" (9.3%). 4. Regarding the educational guidance, both of Korea and the United States emphasis the interrelation of the basic concepts and principles within the total framwork. Also observation and experimentation, safety education, interest of students, life dignity, pretection of nature, social biology are reguired being paid special attentions. 5. In case of evaluation, both of Korea and the United States are the same in all of methods of evaluation. But the United States is grest stressed on reading and writing.

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Photosynthetic characteristics and chlorophyll of Vitex rotundifolia in coastal sand dune

  • Byoung-Jun Kim;Sung-Hwan Yim;Young-Seok Sim;Yeon-Sik Choo
    • Journal of Ecology and Environment
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    • v.47 no.3
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    • pp.103-116
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    • 2023
  • Background: This study analyzed the physiological adaptations of a woody plant, Vitex rotundifolia, in Goraebul coastal sand dunes from May to September 2022. Environmental factors and physiological of plants growing under field and controlled (pot) conditions were compared. Results: Photosynthesis in plants growing in the coastal sand dunes and pots was the highest in June 2022 and July 2022, respectively. Chlorophyll fluorescence indicated the presence of stress in the coastal sand dune environment. The net photosynthesis rate (PN) and Y(II) were highest in June in the coastal sand dune environment and July in the pot environment. In August and September, Y(NPQ) increased in the plants in the coastal sand dune environment, showing their photoprotective mechanism. Chlorophyll a and b contents in the pot plant leaves were higher than those in the coastal sand dune plant leaves; however, chlorophyll-a/b ratio was higher in the coastal sand dune plant leaves than in the pot plant leaves, suggesting a relatively high photosynthetic efficiency. Carotenoid content in the coastal sand dune plant leaves was higher in August and September 2022 than that in the pot plant leaves. Leaf water and soluble carbohydrate contents of the coastal sand dune plant leaves decreased in September 2022, leading to rapid leaf abscission. Diurnal variations in photosynthesis and chlorophyll fluorescence in both environments showed peak activity at 12:00 hour; however, the coastal sand dune plants had lower growth rates and Y(II) than the pot plants. Plants in the coastal sand dunes had higher leaf water and ion contents, indicating that they adapted to water stress through osmotic adjustments. However, plants growing in the coastal sand dunes exhibited reduced photosynthetic activity and accelerated decline due to seasonal temperature decreases. These findings demonstrate the adaptation mechanisms of V. rotundifolia to water stress, poor soils, and high temperature conditions in coastal sand dunes. Conclusions: The observed variations indicate the responses of the V. rotundifolia to environmental stress, and may reveal its survival strategies and adaptation mechanisms to stress. The results provide insights into the ecophysiological characteristics of V. rotundifolia and a basis for the conservation and restoration of damaged coastal sand dunes.

Feeding habit of the River Sculpin, Cottus poecilopus from the Streams at Mt. Chiak, Korea (치악산 계류에 서식하는 둑중개(Cottus poecilopus Heckel)의 식성)

  • Byeon, Hwa-Kun;Sim, Ha-Sik;Choi, Jae-Suk;Son, Yong-Mok;Choi, Jun-Kil;Jeon, Sang-Rin
    • Korean Journal of Ichthyology
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    • v.7 no.2
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    • pp.160-170
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    • 1995
  • The authors investigated feeding habit of river sculpin(C. poecilopus) were conducted at the Chiak streams from April 1993 to March 1994. The feeding habit of C. poecilopus was mainly acquatic insects, such as Ephemeroptera, Odonata, Plecoptera, Trichoptera, Coleoptera, Diptera, and Nematoda, teleost fishes, fish egg and terrestrial insects. Terrestrial insects in the stomach contents were found mainly in autumn, and teleost fish(Moroco oxycephalus) was in summer. Aquatic insects(Ephemeroptera, Trichoptera and Diptera) constituted the bulk of food items ingested during each season. The prey selection indices for Ephemeroptera were positively selected in summer, and negatively selected in autumn and winter, Tricoptera and Diptera were positively selected in autumn and winter, and negatively selected in summer. Additionally, analysis for stomach contents of guarding males suggests that the parental males eat their own eggs during egg guarding(filial-cannibalism).

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Losses of Biomass and Mineral Nutrients during Decomposition of Herbaceous Plants in Riverine Wetlands

  • Kim, Sa-Rin;Kim, Jae-Geun;Ju, Eun-Jeong;Lee, Yang-Woo;Lee, Bo-Ah;Kim, Heung-Tae;Nam, Jong-Min
    • Journal of Ecology and Environment
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    • v.29 no.5
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    • pp.469-478
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    • 2006
  • The composition changes of litters were investigated to figure out the effects of the decomposition of Humulus japonicus on nutrient circulation and decomposition process in the riverine wetlands: Tan stream and Amsa-dong. Litterbags (mesh size 1 mm and 5 mm) were installed to monitor mass and nutrient changes of 5 types of litters: H. japanicus only, Miscanthus sacchariflarus only, Phragmites communis only, mixed litters including H. japonicus, and mixed litters without H. japonicus for 7 months. It was shown that k (decay rate) of the H. japanicus ($2.68{\sim}3.12$) was higher than that of M. sacchariflorus ($1.83{\sim}2.16$) and P. communis ($0.02{\sim}1.18$). The mass and organic remainings of the mixed litters including H. japonicus at Tan stream were $47.0{\sim}55.1%\;and\;47.0{\sim}54.9%$ and those of the litterbags without H. japanicus were $49.2{\sim}65.4%\;and\;47.1{\sim}57.5%$, respectively. This result indicated that the nutrient circulation was faster at H. japanicus community than others. Ca, Na, Mg, K, P, C, N and H contents reduced to around $40{\sim}80%$ of original. However, Na concentration increased up to $407{\sim}584%$ at 100 days and decreased to $248{\sim}498%$ at the end of the experiment. Decomposition rates were similar between 1 mm and 5mm mesh size litterbags and this implies that plant litters in studied areas decomposed mainly by microbes rather than small animals. This study revealed that the fast growth of H. japonicus was resulted from fast decomposition in part: positive feedback of nutrient cycling.

Changes in Chemical Composition and Biological Activities of Original Crude Drugs by Food Processing Techniques III - Changes of HMF Contents from Roasted Asparagi Tuber - (식품학적 가공에 의한 생약의 성분 및 활성 변화 III - Roasting 처리에 의한 천문동 중 HMF 함량변화 -)

  • Kwak, Hye-Min;Kim, Ja-Young;Lim, Jung-Hyun;Chung, Shin-Kyo;Kwon, Soon-Ho;Jeong, Hyun-Hee;Hur, Jong-Moon;Song, Kyung-Sik
    • Korean Journal of Pharmacognosy
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    • v.36 no.3 s.142
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    • pp.235-239
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    • 2005
  • Changes in chemical composition of the ethanolic extract of roasted Asparagi Tuber were investigated by HPLC. One dramatically increased peak $(t_R\;14.85 min)$ was isolated by silica gel column chromatograph and identified as 5-hydroxymethyl furfural (HMF) by comparing its $1^H-NMR$ data with that of a commercial standard. HMF content reached its maximum level at $190^{\circ}C$ for 60 minutes. Under these conditions, HMF contents in the roasted Asparagi Tuber was increased about thirteen times (9.26mg/g) over the not-roasted control (0.71 mg/g). No significant differences were found in macrophage-activating, prolyl endopeptidase-inhibiting, antioxidative (DPPH), anti-coagulating (activated partial thromboplastin times), and ACE-inhibiting activities between roasted and not-roasted Asparagi Tuber.

Physical and Chemical Characteristics of Dokdo Soil

  • Lee, Gil-Seong;Choo, Yeon-Sik
    • Journal of Ecology and Environment
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    • v.32 no.4
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    • pp.295-304
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    • 2009
  • To understand the properties of soil in Dokdo, we collected soil samples from 12 locations on Seodo and 23 locations on Dongdo, in Dokdo of Gyeongsangbuk-do Province in 2007-2008 and analyzed the soil's physical and chemical characteristics. Sand comprises the largest component (49.37%) of Dokdo soil, followed by silt (40.70%) and clay (9.93%). The soil structure consists mostly of sand loam, followed by loam and silt loam. The pH level of soils from Dokdo varied dramatically among sampling sites and seasons, ranging from 3.36 to 8.02. The total ion content of Dokdo soil also varies greatly among survey places and periods, but in general the total ion content was high in summer when vegetation develops, and low in spring. The exchangeable cation contents of the soil showed low levels in samples where the soil pH was low, including habitats dominated by Agropyron tsukushiense var. transiens and Echinochloa crus-galli, whereas the exchangeable cation contents were high where the organic contents were high, as in habitats dominated by Liriope platyphylla and Artemisia japonica subsp. littoricola. Soil N contents varied greatly among survey sites and higher N contents were found in soil inhabited by Chenopodiaceous plants than in habitats inhabited by other plants. The substantial differences in phosphorus contents among sites were related to excrement of black-tailed gulls. To understand the basic physical and chemical features of the soil on Dokdo, it will be necessary to conduct seasonal and long-term research on soil pH, ion contents, organic contents, N and P, as well as obtaining precise data from samples collected at different depths.

Adventitious root growth inhibition in boron-deficient or aluminum-stressed sunflower seedlings

  • Kim, Tae-Yun;Go, Eun-Jung;Jung, Sang-Deck;Kim, Hyo-Jin;Hong, Jung-Hee
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2003.05a
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    • pp.261-262
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    • 2003
  • Sunflower(Helianthus annuus L.) seedings were de-rooted and grown in nutrient solutions providing either deficient or sufficient boron supply and supplemented with aluminum. Increasing concentrations of aluminum in the nutrient medium caused progressive inhibition of root growth and a parallel increase in proline level of roots. Elevated boron levels improved root growth under toxic aluminum conditions and produced higher proline contents. Exogenous ascorbate improved adventitions root growth in plants supplied with insufficient boron and aluminum. These findings suggest that root growth inhibition resulting from either boron deficiency or aluminum toxicity may be a result of impaired ascorbate metabolism.

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A Study on the Heavy Metal Tolerance in Several Herbaceous Plants (수종 초본식물의 중금속 내성에 대한 연구)

  • Cho, Do-Soon;Joon-Ho Kim
    • The Korean Journal of Ecology
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    • v.18 no.1
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    • pp.147-156
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    • 1995
  • Restoration of ecosystems degraded by heavy metal pollution can be accomplished by soil amendment and selection and utilization of plants tolerant to heavy metals. Two former zinc mine sites, Sambo Mine in Hwasung, Kyonggi-do and the Second Yonhwa Mine in Samchuk, Kangwon-do, were selected for collection of plant samples and for determination of heavy metal tolerant species. Dominant species on mine waste deposits in Hwasung site were Panicum bisulcatum and Echinoch/oa crus-galli, while those in Samchuk site were Aster yomena, Setaria viridis, Artemisia lavandulaefolia and Oenothera odorata. Mean contents of zinc, lead and cadmium in Hwasung soil were 103, 117 and 1 ppm, respectively, while those in Samchuk soil were 23, 6 and 4 ppm, respectively, Zinc contents were higher in Echinochloa crus-galli from Hwasung and in Artemisia lavandulaefolia from Samchuk, while lead contents were higher in Panicum bisulcatum and Echinochloa crus-galli from Hwasung and Lactuca sonchiJolia and Pinus densiJolia from Samchuk. Plant species with higher cadmium contents were Panicum bisulcatum and Lactuca sonchiJolia. Comparison of metal contents between roots and shoots showed that Echinochloa crus-galli was a zinc accumulator, while Panicum bisulcatum, Persicaria hydroPiPer, Pinus densiJlora and Lactuca sonchiJolia were zinc excluders. In addition, Panicum bisulcatum and Persicaria hydroPiPer were proved to be lead excluders. When both heavy metal contents in plant tissues and biomass of individual plants are considered, it can be concluded that Echinochloa crus-galli and Panicum bisulcatum from Hwasung and Artemisia lavandulaefolia and Aster yomena are heavy metal absorbing plants. The effect of heavy metals on seed germination showed that Artemisia princeps var. orientalis had higher germination rates, but no significant difference in concomitant decrease of germination rates among the species investigated were found by increasing heavy metal contents.

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Total Phenol Contents and DPPH Radical Scavenging Activity of Entomopathogenic Fungi (곤충병원성진균의 총 페놀 함량 및 DPPH 라디칼 소거능)

  • Lee, Ki-Man;Nam, Sung-Hee;Song, Ha-Suk;Yeo, Joo-Hong;Lee, Kwang-Gill;Bae, Yoon-Hwan
    • Korean journal of applied entomology
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    • v.48 no.3
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    • pp.377-383
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    • 2009
  • This study was conducted to investigate the total phenol contents, antioxidative activities and antibacterial activities of twenty species of entomopathogenic fungi. The total phenol content was highest in Aspergillus flavus ($553.0{\pm}52.15{\mu}g/g$) and A. parasiticus ($529.9{\pm}60.10{\mu}g/g$). On the other hand those in other strains were within the range of $26.6{\sim}121.9{\mu}g/g$. The antioxdative activity was shown in the most of strains and the highest DPPH (1, 1-diphenyl-2-picrylhydrazyl) radical scavenging activity was observed in A. flavus ($90.9{\pm}2.90%$) and A. parasiticus ($77.9{\pm}4.13%$). This result indicated that the antioxidative activities were very correlated with the total phenol contents. The antibacterial activitiy was found in the every tested pathogenic bacteria. Especially, the antibacterial activity was strongest against Listeria monocytogenes and Escherchia coli.