• 제목/요약/키워드: dimorphism

검색결과 135건 처리시간 0.04초

채송화(Portulaca grandiflora Hook)의 계절에 따른 동종이형현상과 돌나무과형 유기산대사에 관한 연구 (Characteristics of CAM and Seasonal Dimorphism in the Succulent $C_4$ Dicot, Portulaca grandiflora Hook.)

  • Chang, Nam Kee;Chang Duck Jin
    • 환경위생공학
    • /
    • 제5권2호
    • /
    • pp.89-99
    • /
    • 1990
  • Morphology, anatomy and diurnal acid fluctuations were investigated monthly for the succulent C4 dicot Portulaca grandiflora Hook. growing under natural environmental conditions. Modified Kranz-Type sturcture and typical CAM-like cells were shown in leaves and stems, respectively. Values of indices of mesophyll succulence inleaves stems were 5.62 and 16.68, respectively. The number of stomata were 1476$\textrm{cm}^{-2}$ in leaves while the stomata in stems were not observed through growing seasons from spring to summer. However, on Sep. 16, 1981 in defoliate autumn season, stomata were begun to be produced for the first time in stems and the number were increased gradually to 216$\textrm{cm}^{-2}$ on Oct. 29. This feature can be interpreted as a seasonal plant dimorphism. P. grandiflora exhibited a diurnal fluctuation of titratable acidity in leaves and stems. Seasonal amplitudes of acid fluctuation in stems were as follows: 27 $\mu$eq./g.f.wt. on Sep. 21; 57$\mu$eq/g.f.wt. on Oct. 3; 80$\mu$eq./g.f.wt. on Oct. 21. Such the results in seasonal amplitude were able to consider due to decrease of light period and cool night air temperature according to change of season. Also, the naturally defoliated stems which had already stomata exhibited usual diurnal acid fluctuation, on the other hand the treated stems which possessed artificially closed stomata showed a few of acid fluctuation. Especially, stomata in stems are developed by seasonal dimorphism and activated stomata participate in CAM behavior of stems.

  • PDF

공초점현미경을 이용한 암수 흰쥐 청색반점의 비교연구 (Study for comparison with male & female rat locus coeruleus using confocal laser scanning microscopy)

  • 박일권;송치원;이경열;권효정;김무강;이강이;정영길;이남섭;하권수
    • 대한수의학회지
    • /
    • 제40권3호
    • /
    • pp.451-461
    • /
    • 2000
  • The locus coeruleus(LG) is known to be observed a sexual dimorphism in rat CNS. LC is the largest collections of norepinephrine(NE)-containing neurons in the mammalian brain. Especially in rat, all LC neurons contained NE unlike other mammalians, so that specific reactions were found in the tyrosine-hydroxylase(TH) immunoreactive neurons. Sexual dimorphism of rat LC has affected by genes before sex hormone appeared, thereafter affected by sex hormones. In these day, many scientists founded morphological differences between male and female LC morphology, but differences of entire structure was not founded. Thus we investigated sex differences of the LC neuron's morphology in rat by three-dimensional(3-D) reconstruction using Confocal laser scanning microscopy(CLSM). We reported that neuron's shape was relatively-large multipolar neurons and neuron's processes in dorsal LC proceeded to ventral direction in the male and female rat. Male had a longer anterior-posterior length than female had in dorsal LC. In addition to middle-LC, male rat's LC had a more thicker posterior region but had not viewed in a previous study. In reverse, female rat's LC had a thicker anterior region like a previous study. This results using 3-D reconstruction by CLSM showed that the male's LC was more wide-ranging than female's relatively.

  • PDF

Gynodioecy and floral dimorphism of Glechoma longituba (Nakai) Kuprian. (Lamiaceae) in Korea

  • Jang, Tae-Soo;Hong, Suk-Pyo
    • 식물분류학회지
    • /
    • 제41권3호
    • /
    • pp.202-208
    • /
    • 2011
  • The present study was focused on the careful investigation of Glechoma longituba flowers collected from four populations in Korea to clarify their precise sexual systems. All floral characters of this taxon were examined by using a stereo microscopy. The nutlet size and production were compared between two distinct morphs (i.e., hermaphrodites and females), and pollen viability test of hermaphrodite and intermediate phenotype (i.e., individuals with a mixture of females and perfect flowers) was also observed by light microscopy (LM). All of the investigated floral characters of G. longituba are significantly different from one sexual morph to another. Hermaphroditic plants were larger than the female ones in corolla width and length, calyx length, filament length, anther length, and style length (all P < 0.0001, respectively). However, the nutlet width of the female plants was larger than those of the hermaphrodites (P = 0.013). Nutlet production of females was higher than hermaphrodites in Na-Ju population [H (Hermaphrodite): ca. 17.76%, F (Female): ca. 37.45%], but in Mun-San population was no significant difference between these sexual morphs (H: ca. 57.52%, F: ca. 53.16%). We have found significant differences between the fertile pollen grain of hermaphrodite and sterile pollen grain of intermediate phenotype based on pollen size and viability. The results of the present study suggest that compensation (flower size dimorphism, seed set, and pollen viability) is one of the main mechanisms in order to maintain female plants in gynodioecious G. longituba.

배양세포의 성염색질에 관한 세포학적 연구 1. 배양기간을 달리한 고양이, 몰못트, 닭의 배양세포에 있어서의 성염색질에 대하여

  • 강영선;박상대
    • 한국동물학회지
    • /
    • 제8권2호
    • /
    • pp.37-41
    • /
    • 1965
  • The frequency and pattern of sex chromatin in primary cultured cells of kidney cortex of cats and guinea-pigs, and muscle of chick embroys were examined and compared to those of in vivo condition, with special reference to the various cultured stages. 1. In cat, the frequencies of sex chromatin positive I of peripheral position were average 62.7% in female, and 15% in male, whereas those of non-peripherla position were 5.8% in female and 0.1% in male. The incident proportion between them showed a marked difference-approximately 10 times higher in female than male. These results failry indicated that a distinct nuclear dimorphism with regard to the sex chromatin positive I was established in cultured cells. The position of sex chormatin was usually peripheral location. The tendency of frequencies , with reference to the cultured stages, was low count in primary extracted and initial stage cells , but it showed a peaked frequency in 10-13 days after primary culture, and after that the frequencies were decreased gradually. Compared between I vitro and in vivo condition of the same tissues, the cells in vivo exhibited the sex chromatin in high frequency at the peak showed stage. 2. In guinea-pig , the frequencyies of peripheral positive I were 36.8% in female and 6.3% in male, while non-peripheral positions were 6.1% in female and 3.5% inmale. Its incident was a rate of nearly 4 times higher in female than male. The nuclear dimorphism was also established in cultrued cells of guinea-pig. The position and the incident frquency showed a similar pattern as in cat except the primary extracted cells. 3. In chick embryo, the frequencies of sex chromatin positive I of peripheral position were 38.2% in female, and 18.3% in male, non-peripheral position, however, was hardly to find. These results suggest that the definite sexual dimorphism was unable to find in chick embryo cultured cells. The position and the incident tendency were a similar pattern as in above mammals and the frequency was higher in vitro cells.

  • PDF

하늘다람쥐(Pteromys volans)의 형태적 특성: 성적이형성 및 위도에 따른 형태학적 특성 비교 (Morphological Characteristics of Siberian Flying Squirrel (Pteromys volans): Sexual Dimorphism and Camparison of Morphological Characteristics in Different Latitudes)

  • 김준수;전종훈;이우신;김종우
    • 한국산림과학회지
    • /
    • 제108권1호
    • /
    • pp.133-137
    • /
    • 2019
  • 하늘다람쥐의 형태적 특성을 파악하기 위해 강원도 원주시 백운산에서 2014년 4월부터 2016년 3월까지 하늘다람쥐의 6가지 외부형태적 특성에 대한 측정을 실시하고 분석하였다. 그 결과 하늘다람쥐는 암컷이 수컷보다 큰 암컷편향적 성적이형성을 나타내는 것으로 확인되었다. 이는 단독 생활을 하고 암컷 혼자 새끼를 키우는 하늘다람쥐의 번식전략과 관련이 있는 것으로 보인다. 국내와 핀란드, 일본에서 파악된 하늘다람쥐의 외부형태 측정치 중 체중과 머리-몸통의 길이를 비교한 결과, 모두 핀란드와 일본 그리고 한국 순서대로 위도가 높은 지역이 크게 나타났다. 이러한 형태적 특성의 차이는 분포 지역 위도에 따른 기후와 서식환경 차이에 따른 것으로 생각되며, 추후 체중과 머리-몸통의 길이 이외의 외부형태 측정치에 대한 비교 연구가 필요할 것으로 생각된다.

영양 수준의 향상에 따른 신장 성적이형성의 변화: 탈북자 자료를 이용한 남북한 비교연구 (A Study of the Relationship between the Nutritional Quality of Life and Stature Sexual Dimorphism)

  • 박순영
    • Journal of Nutrition and Health
    • /
    • 제44권2호
    • /
    • pp.162-170
    • /
    • 2011
  • 본 논문에서는 탈북 성인 남녀의 평균 신장을 남한의 것과 비교 검토함으로써 영양 환경의 질이 향상되면 남녀 간 신장의 성적이형성 (SSD, Stature Sexual Dimorphism)이 커질 것이라는 영양환경 가설을 검증하였다. 연구대상 선정은 두 단계에 걸쳐 이루어졌다. 우선, 1997년부터 2007년 4월까지 남한에 입국하여 신체를 계측한 탈북자 중에서 탈북 당시 연령이 최소 만 20세 이상이어서 성인신장을 북한에서 도달한 것으로 추정할 수 있는 사람들을 일차 표본으로 선정하였다. 이 일차 표본 중에서 1955년에서 1959년 사이에 출생한 사람들과 1980년에서 1984년 사이에 출생한 사람들을 최종 선정하여 탈북자들 사이의 세대 간 변화를 비교하였다. 남북한 비교를 위해서는 남한의 Size Korea 2004 자료를 이용하였다. Size Korea 2004 자료에서 만20세 이상 성인으로서 탈북자 표본과 같은 시기 즉, 1955년에서 1959년 사이 그리고 1980년에서 1984년 사이에 출생한 사람들의 SSD를 계산하여 탈북자 자료와 비교하였다. SSD의 크기 변화를 통계적으로 검증하기 위해서는 Greene (1989)의 검증법을 이용하였다. 조사 결과, 탈북자들 사이에서는 한국전쟁 종전 직후 출생한 세대와 1980년대에 출생한 세대 사이에 평균 신장의 증가가 관찰되지 않았고 신장 성적이형성의 크기에도 변화가 없었다. 반면에 남한에서는 두 세대 사이에 평균 신장의 확연한 증가가 있었는데 남녀 중에서도 남성 집단의 평균신장 증가가 더욱 두드러진 결과로 SSD도 증가하였다. 즉 1980년대 출생자들이 한국전쟁 종전 직후인 1955~59년 사이에 출생한 사람들보다 확연히 큰 SSD를 보여주었다. 이는 영양 환경의 질이 향상되면 남성과 여성 사이의 성적 이형성이 커지는 경향이 나타날 것이라는 영양환경 가설을 뒷받침하는 결과이다.