All issues
Volume 69, Issue 811
Displaying 1-7 of 7 articles from this issue
- |<
- <
- 1
- >
- >|
-
Yoshihiro TSUBO1956 Volume 69 Issue 811 Pages 1-6
Published: 1956
Released on J-STAGE: December 05, 2006
JOURNAL FREE ACCESSDownload PDF (665K) -
Shun-ei ICHIMURA1956 Volume 69 Issue 811 Pages 7-16
Published: 1956
Released on J-STAGE: December 05, 2006
JOURNAL FREE ACCESSThe standing crop and productive structure of phytoplankton communities in some lakes of central Japan have mainly been investigated by chlorophyll extraction method.
1.Remarkable difference of chlorophyll content with lake type was ascertained. In summer, average values of the chlorophyll content in epilimnion are in maximum ca. 50mg/m3 in eutrophic lakes, and less than 1mg/m3 in oligotrophic and dystrophic ones.
2. The chlorophyll content in lakes varied not only in quantity but also in the vertical distribution, -the productive structure of phytoplankton community-, of which two main types, i.e., homogeneous distribution and stratum one (Fig. 3), were recognized and both the types appeared alter nately in the course of year, The process of the transformation of the two types was analysed on the basis of metabolism of phytoplankton.
3.The standing crop of phytoplankton was investigated with the amount of chlorophyll. It showed that in summer the seston was mainly composed of phytoplankton but in winter mainly inorganic matter and non-chlorophyllic organisms.View full abstractDownload PDF (1003K) -
Shizuko KOBAYASHI, Isao HATAKEYAMA, Joji ASHIDA1956 Volume 69 Issue 811 Pages 16-23
Published: 1956
Released on J-STAGE: December 05, 2006
JOURNAL FREE ACCESSThe fresh weight of sectioned pieces of Avena coleoptile did not increase in an auxin solution if this contained lactose or mannitol to cause incipient plasmolysis of the cells. When transferred from the sugar solutions to water, the pieces treated by auxin absorbed more water than those without auxin action. The results suggest that auxin acts to decrease the wall pressure, rather than to increase the absorbing power of cell contents.
O2 uptake, as well as its stimulation by auxin, was not much inhibited in the state of incipient plasmolysis. This partly answers the objection that metabolic activities which support active water absorption might be inhibited under the abnomal osmotic condition.View full abstractDownload PDF (811K) -
Shun-ichiro IMAMURA, Atsushi TAKIMOTO1956 Volume 69 Issue 811 Pages 23-29
Published: 1956
Released on J-STAGE: December 05, 2006
JOURNAL FREE ACCESSThe transmission rate of the photoperiodic stimulus across the graft union in Pharbitis Nil was found to be 2.8 and 2.4mm per hour. The stimulus travels in the grafted plants approximately with the same velocity as in the two-branched plants; the graft union has no significantly hindering effect upon the transmission of the stimulus.View full abstractDownload PDF (690K) -
Shogo SAWAMURA1956 Volume 69 Issue 811 Pages 30-33
Published: 1956
Released on J-STAGE: December 05, 2006
JOURNAL FREE ACCESSThe studies on the mitosis in vivo were carried out on young petal cells in Allium fistulosum and stipular cells in Vicia faba, and the methods and the observational results are described in detail.
On the standpoint of cell biology it is very important that the mitosis in Allium and Vicia, the most common materials in fixed preparations, is now studied in the living state of the cell.View full abstractDownload PDF (1830K) -
Ryohei FUJII1956 Volume 69 Issue 811 Pages 34-38
Published: 1956
Released on J-STAGE: December 05, 2006
JOURNAL FREE ACCESSSugars condained in the alcohol extracts of seed embryos of Vigna sesquipedalis germinated in the dark were studied semi-quantitatively on onedimentional ascending paper-chromatograms.
No other sugar than sucrose, glucose and fructose was detectable, excepting that two unidentified blue-colored spots of relatively high Rf values were made appeared when resorcinol-HCl was sprayed. These sugar-like substances behaved different on paper-chromatogram from galactose, mannose, rhamnose, xylose, arabinose and ribose; they also did not react with the diphenylamine as well as the orcinol reagents.
The seeds before germination contained only sucrose, no hexose being detected. As germination proceeded, glucose and fructose were formed rapidly to predominate soon over sucrose in the epicotyl, hypocotyl and radicle. In plumules, on the contrary, the amount of glucose and fructose did not exceed that of sucrose; the production of fructose in particular was very much small. The cotyledon, as a homologous organ to the plumule, showed a similar sugar pattern to that of plumules, i.e. a bulk of sucrose accompanied by only a scanty amount of glucose and no fructose.
In the cotyledon tissues maltose was absent, and, therefore, the starch degradation might not be performed by the action of amylase but likely by the phosphorylase action instead.
These results would suggest, in accordance with Wanner (1952), that in the cotyledon sucrose may be synthesized from the products of starch degradation, hexoses, and transported as such into the growing parts of the germs to be split again to free hexoses probably by the action of invertase.View full abstractDownload PDF (535K) -
Seibin ARASAKI, Hiroshi TOKUDA, Kazue FUJIYAMA1956 Volume 69 Issue 811 Pages 39-44
Published: 1956
Released on J-STAGE: December 05, 2006
JOURNAL FREE ACCESS1. The field observations on the vegetation and sexuality of Codium fragile have been made for several years during 1940-1949 and 1951-1953 in the central region of the Pacific coast of Japan.
The young plants begin to appear during early winter and spring, then they become luxuriant during early summer and late autumn. The reproductive organs (gametangia) are produced usually from May till December. As for the sexuality, most plants are dioecious and some are monoecious, while the sexual ratio and the ratio of monoecious to dioecious plants are varied in places or seasons.
2. The gametes are anisomorphic, and the conjugation takes place between a macro (female)- and a micro (male)- gamete. The zygote develops into a tufty plant composed of non-septate, sympodially branched filaments. Though the shape of the free filament is variable, the contents of the filament or chromatophores are identical to those of C. fragile. This tufty vaucherioid plant survives over four years becoming much denser, but not into Codium-form probably owing to the unfavourable conditions in the culture vessel.
3. From the field and laboratory observations, it is suggested that the frond of Codium may be made up by the interweaving of the sympodially branched filaments, producing in the beginning the prostrate basal portion then one or more erect portions. And also it is suggested that these filaments may be originate in a zygote or in a few zygotes: that is to say homogeneous or heterogeneous. If this assumption is acceptable, much variety in sex differentiation in Codium fragile seems to be explained by such flexibility in the process of the morphogeny.View full abstractDownload PDF (866K)
- |<
- <
- 1
- >
- >|