• Journal of the Korean earth science society
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• v.28 no.2
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• pp.169-178
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• 2007

In this research we diagnosed the actual status of the 7th National science elective curriculum and suggested a way to select and organize the content of the new science elective curriculum. The first science education reform was grounded in the structuralism where the structure of discipline was valued above everything else. On the other hand, the second science education reform suggested alternative interpretations of students' opportunity to learn, putting a brake on the structuralist thinking. According to the survey result, the majority of the science elective courses are in need for revision because the contents are overcrowded, too difficult in light of students' learning readiness, failed to draw students' interest in science, and are overlapped and repeated among the 10th grade science, high school science I and II. In particular, Earth Science II and physics II are the most unfavorable courses among students. Thus, we recommended a fundamental change be made in the new curriculum in addition to the optimization of the content. In this paper, we suggested 'topic-centered content organization' for the science elective course I, i.e., Physics I, Chemistry I, Biology I and Earth Science I that is designed for both science track and non-science track students. Since curriculum provides students with an 'opportunity to learn', a curriculum study should focus on what the 'opportunity to learn' is that students ought to be offered. Based on the result of this study, we recommended one way to select and organize the content of high school elective curriculum.

• The Korean Journal of Zoology
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• v.18 no.3
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• pp.107-114
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• 1975

This study was performed in order to know the histochemical changes of mucosubstances in granular secretions of the serous gland under normal and dry conditions. The frogs were collected near Jinju and the experimental groups were retained under dry conditions for 24, 48, 72 and 96 hours to make a comparison with normal group. The results obtained were as follows: 1. The secreting granules in serous gland of the frog skin contained neutral and weakly acidic mucosubstances. 2. the secreting granules in serous gland of the frog skin were significantly decreased under dry conditions, as is evident from the histochemical properties. The neutral mucosubstances were decreased more than acidic mucosubstances. 3. Histochemical compositions of the mucosubstances of secreting granules in the lumen of the serous gland were not changed according to dry condition.

• The Korean Journal of Zoology
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• v.36 no.2
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• pp.293-303
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• 1993

쇠오징어(Sepiella maindroni)흠반의 외측 상피조직에서 3종류의 감각세포(A, B 및 D형 감각세포)와, 1종류의 감각상피세포(C형 감각 상피세포) 그리고 2종류의 점액세포(a 및 b형 점액세포)가 각각 관찰되었다. A 및 B형 감각세포는 분포상태가 다를 뿐 형태는 거의 유사한 세포이고 많은 분비액포를 지닌 해면질 형태의 세포로서 전자 밀도가 낮은 물질을 분비하는 분비성 감각세포로 확인되었다. 0형 세포는 매우 작은 감각세포로서 세포의 자유면에 긴 융모가 밀생되어있었고, 측면원형질막은 불규칙한 수지상 연접을 이루고 있었다. 이 세포는 전자밀도가 매우 높아서 검게 보였다. C형 감각 상피세포도 세포의 자유면에 긴 미세융모가 밀생되어있는 단층 원주상 세포로서. 이 세포 역시 측면원형질막이 불규칙한 수지상 연접을 이루고 있고. 엽접내에는 많은 소포와 약간의 사립제가 관찰되었다. 3형 점액세포는 세포질속에 내강이 팽창된 활면소포체를 소지하고 있으며 전자밀도가 높은 구형의 점액과립을 형성하였고, b형 점액세포도 전자밀도가 중등도인 점액질 과립을 소지하고 있었다.

• The Korean Journal of Zoology
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• v.35 no.3
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• pp.395-403
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• 1992

화에 따른 연두금파리(Lucilia illustris Meigen) 타액선의 미세구조 변화와 타액선 내부에 함유된 분비물질의 형성과정 및 물질의 성분을 전자현미경 및 효소세포화학적 방법으로 관찰하였 다. 종령유충기의 타액선은 식도의 좌우에 위치한 한쌍의 반투명한 관으로 단층으로 배열된 편평형의 세포들로 이루어져 있었다. 세포질에는 조면소포체와 골지복합체가 풍부하였고, 세포내 물질의 생성이 매우 활발하였으며, 세포질내에 축적된 분비과립은 부분분비에 의해 배출되었다. 전용기의 타액선은 세포가 비후해짐에 따라 타액선의 내감이 줄어들며 타액선의 길이도 감소하였으며, 세포질내 조면소포체의 양적 감소와 대형분비과립의 형성이 현저하였다. 용기에는 대형의 자식성 액포들이 황범위하게 형성되어 있었으며 이는 유충시기의 타액선이 변태과정을 거치며 퇴화되는 것으로 사료되었다. 타액선 세포에 대한 acid phosphatase외 반응은 주로 내강면에 인접한 리소조옴에서 양성반응이 나타났으며, 종령유충 시기의 타액선 세포질내 지질성분은 주로 기저부에 존재하였으나, 용 형성 48시간 이후에는 관찰되지 않았다.

• The Korean Journal of Zoology
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• v.33 no.3
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• pp.354-364
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• 1990

The ultrastructure and silk formational process of the flagelliform glands, one of the capture thread producing organs in the orb web spider (Nephila clavata L. Koch), have been studied with electron microscope. A pair of flagelliform glands consist of three distinct regions: excretory duct, storage sac and convoluted tail. This gland is connected to the large spinning tube (spigot) of the posterior spinnerets with two pairs of aggregate glands, and showed a characteristic spigot structure called "triad". The excretory duct consists of three long segments surrounded by the same sheath of connective tissue. The distal duct near the spinning tube bears the electron lucent subcuticles which have the functions of water removal and orientation of the silk fiber, whereas the proximal duct near the sac contains the cuticule precursor transported through the intercellular space. Cytoplasms of the sac and tail regions have well developed rough endoplasmic reticulum and contain the round secretory granules commonly, but the electron densities and internal textures of the granules do not coincided. Adjacent epithelial cells are connected with the specialized septate junctions, and secretory granules accumulated at the apical pole are released to the lumen by the apocrine secretion.secretion.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.3
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• pp.257-261
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• 2000

Integumentary system of the polychaete, Perinezeis aibuhitensis was consisted cuticular, epidermal and dermal layers. Excretory pores opened in cuticular layer, which is covered with epicuticular projections. The hemidesmosomes were observed between supporting cell and basal area of cuticular layer. The epidermal layer was consisted supporting cells and unicellular glands. Supporting cell was relatively larger than the other neighbouring cells, and the nucleus had one to two nucleolus. Cytoplasm of the supporting cell had well-developed intracellular organs such as tonofilaments, mitochondria, rough endoplasmic reticula, free ribosomes and pigment granules of electron dense. The gland cells were reacted with blue in AB-PAS, and classified into the three types such as ${\alpha},\;{\beta}\;and\;{\gamma}$ from the transmission electron microscopic observation. Type ${\alpha}$ gland cell was ovoid and the cytoplasm had well-developed tonofilaments and membrane bounded secretory granules of $0.8{\~}1.5 {\mu}m$ in diameter. Type ${\beta}$ gland cell had a large vacuole and secretory granules of $0.5{\~}0.8 {\mu}m$, which scattered evenly in the cytoplasm. Type ${\gamma}$ gland cell had well-developed endoplasmic reticulum, Golgi auparatus and secretory granules of $0.2{\~}0.3 {\mu}m$ in diameter. The electron density of this granules was the highest among the granules.

• Applied Microscopy
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• v.37 no.1
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• pp.43-52
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• 2007

In order to observe the localization of excretory, purified and infected antigenic protein in the tissue of Trichinella spiralis larvae, immunogoldlabeling methodology using IgG and protein A-gold complex was implemented. T. spiralis larvae obtained from rat muscle were initially cultured in medium, and secreted excretory antigen was collected for 1 or 3 days. Purified antigenic protein was obtained from homogenized T. spiralis larvae. Rabbits were then immunized with 1 or 3 days secreted excretory protein and purified 45 kDa protein, and IgG was purified from collected serum. Serum, against infected antigen, collected from rat on 1 and 4 weeks after infection with T. spiralis larvae, and IgG was purified from collected serum. T. spiralis larvae were embedded in Lowicryl HM20 medium. Then they were finally treated with immunized IgG and protein A-gold complex (particle size; 15 nm) and observed under electron microscope. In T. spiralis larvae tissue, the tissue antigen reacted with rabbit IgC antigen Day 1 secreted excretory protein, infected antigenic protein and purified 45 kDa protein. But different distribution pattern of labeled gold particles were observed. When Day 1 secreted excretoy protein was used, gold particle labeling was observed specifically on the cuticle, basal layer, esophagus interstitial matrix (EIM) and ${\alpha}_0,\;{\alpha}_1$ granules of stichocyte of the worm. In a separate group of tissue, the antigen reacted with rabbit IgG against Day 3 secreted excretory protein. Labeled gold particles were specifically distributed on the surface layer of cuticle, EIM and ${\alpha}_0$ granules of stichocyte of the worm. In case of using infected antigenic protein, gold particle labeling was specifically distributed on the cuticle and EIM of the worm. When purifed 45 kDa protein was used gold particle labeling was specifically distributed on the cuticle, basal layer, EIM and ${\alpha}_0,\;{\alpha}_1$ granules of stichocyte of the worm. Therefore, excretory antigens appeared to originate from the cuticle and ${\alpha}_0,\;{\alpha}_1$ granules of stichocyte for the first day but the cuticle layer associated with globular proteins and ${\alpha}_0$ granules of stichocyte after 3 days and infected antigens appeared to originate from the cuticle for 1 and 4 weeks after infection. These results suggest that excretory and infection specific antigens are secreted into the cuticle, basal layer, EIM and ${\alpha}_0,\;{\alpha}_1$ granules of stichocyte and 45 kDa protein may be contained these specific antigens.

• The Korean Journal of Zoology
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• v.37 no.1
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• pp.88-96
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• 1994

고양이의 시상하부내 SON과 PVN에서 VP분비신경원과 OT분비신경원의 형태와 분포를 관찰하기 위해서 면역조직화학적 반응을 시행하였다. 광학 및 전자 현미경적 관찰에 의하면 VP분비신경원과 OT분비신경원의 형태 차이는 없었다. 이들의 형태는 방추형, 타원형 그리고 원형이었으며 크기는 25-40mm으로 나타났다. SON은 시삭위에 능형의 형태로 나타나고 OT분비신경원과 VP분비신경원의 비율은 1:2.4이며 PVN은 제3뇌실을 따라 삼각형 모양으로 나타나고 VP분비신경원과 OT분비신경원의 비율은 1:1.6으로 나타났다 전자현미경적 관찰에 의하면 VP분비신경원과 OT분비신경원에서 과립형질내세망, 사립체, 골지장치, 그리고 미세소관 등이 특히 잘 발달되어 있음을 관찰할 수 있었다.

• Applied Microscopy
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• v.34 no.3
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• pp.199-209
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• 2004

The migut epitheluim of the last instar larva in the mosquito larvae, Anopheles sinensis was observed with electron microscopes. The midgut epitheluim of the mosquito larva is composed of a single-layered columnar absorptive cells, regenerative cells and secretory granular cells. The free surface of the columnar absorptive cells has a regular array of microvilli 'brush border', while cell membranes close to the basal lamina are extrmely infolded and a lot of mitochondria are concentrated in those processes. The columnar absorptive cells also contain cell organelles expected to be found in absorptive cell. Midgut regenerative cells which are positioned basally in the epithelium form the groups, which are called 'nidi', composed of 1 or $2{\sim}3$ cells, they show darker appearance than the columnar absoptive cells. The secretory granular cells contain numerous electron dense granules, $200{\sim}400$ nm in diameter. The cone shaped secretory granular cells are located in the basal portion of the midgut epitheluim. The epithelium is surrounded by the subepithelial space and muscle bundles. The subepithelial space, which is filled with fibrous connective tissue, is innervated by many axon cells and tracheoles.

• Applied Microscopy
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• v.26 no.1
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• pp.17-31
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• 1996

The venomous apparatus of the black widow spider, Latrodectus mactans, is composed of chelicera and paired venom glands in the cephalothorax. Each glands is surrounded by a thin adventitia and striated muscular bundles resting on a basal membrane. Along the musculature neuromuscular synaptic contacts are formed by a motor axon and the muscle fibers. The secretory epithelium, which made up of simple and long columnar cells with extensive finger-like processes, creates a simple acinar gland. The secretory surfac is increased by a sort of fringes extended from the basal membrane into the gland lumen, and the luminal surface of the epithelium is marked by the presence of closely spaced microvilli. The venoms of the black widow spider are produced from two types of secretory granules within the epithelial cells. During the secretory phase, these granules are transformed into droplets and suffering a condensation. Finally the secretory products are released by the apocrine secretion. After the gland is emptied, the basal epithelial cells present a high proliferative process and regenerate the columnar epithlial cells.