Rhizoid formation inValonia(Siphonocladales, Chlorophyceae)

Phycologia ◽  
2012 ◽  
Vol 51 (4) ◽  
pp. 391-402 ◽  
Author(s):  
Paul Rommel Elvira ◽  
Satoko Sekida ◽  
Kazuo Okuda
Keyword(s):  
Rhizoid Formation

scholarly journals Changes in cell wall structure during rhizoid formation of Silvetia babingtonii (Fucales, Phaeophyceae) zygotes

2021 ◽  
Author(s):  
Rina Yonamine ◽  
Kensuke Ichihara ◽  
Shiro Tsuyuzaki ◽  
Cécile Hervé ◽  
Taizo Motomura ◽  
...  
Keyword(s):  
Cell Wall ◽  
Cell Wall Structure ◽  
Wall Structure ◽  
Rhizoid Formation

Sporeling development in the genus Exormotheca. 1. Exormotheca ceylonensis

1968 ◽  
Vol 46 (8) ◽  
pp. 1009-1012 ◽  
Author(s):  
Ram Udar ◽  
S. C. Srivastava
Keyword(s):  
Germ Tube ◽  
Plate Formation ◽  
Rhizoid Formation

The sporeling development in E. ceylonensis has been described. The germ tube emerges through the distal face of the spore. The plate formation is of two types: the Stephensoniella type and the Asterella type. The germ rhizoid formation is of the Stephensoniella type.

scholarly journals ELECTRICAL CONTROL OF RHIZOID FORMATION IN THE RED ALGA, GRIFFITHSIA BORNETIANA

1934 ◽  
Vol 18 (1) ◽  
pp. 1-21 ◽  
Author(s):  
Victor Schechter
Keyword(s):  
Red Alga ◽  
Ph Change ◽  
Electrical Field ◽  
Galvanic Current ◽  
Electrical Control ◽  
Differentiated Cells ◽  
Cytoplasmic Bodies ◽  
Bright Pink ◽  
Rhizoid Formation

1. Direct galvanic current of 10 to 40 microamperes per square millimeter of cross-section of medium results in anodal determination of rhizoid origin in the differentiated cells of the red alga Griffithsia bornetiana. The current is most effective near the upper end of the range. 2. Within the range used there is an increase in the number of rhizoids produced with increase in current intensity and a decrease in size of rhizoids. 3. Currents of lower intensity require a longer time to produce these effects than comparatively high currents. 4. The orientation of the plants in the electrical field seems to affect the number of rhizoids produced, in that plants with apexes toward the anode produce more rhizoids. 5. Together with anodal rhizoid determination there is migration of chromatophores toward the anodal side of each cell. 6. Displacement of chromatophores (and other cytoplasmic bodies) by the centrifuge does not affect the point of rhizoid origin, but does affect the shoots. 7. Together with anodal determination of rhizoids the algal filaments become graded in color, from bright pink toward the cathode to pale tan toward the anode. 8. Evidence is presented to show that this is not due to a pH change, but to a loss of pigment by chromatophores toward the anode and electrophoresis of the pigment toward the cathode. 9. In conclusion the probability is pointed out that the current acts in morphogenesis by moving particles of different charge.

Self-Organization in a Rhizoid Formation of Fucus Eggs

1982 ◽  
Vol 51 (9) ◽  
pp. 3049-3056 ◽  
Author(s):  
Kiyoshi Toko ◽  
Kaoru Yamafuji
Keyword(s):  
Self Organization ◽  
Rhizoid Formation

scholarly journals Rhizoid Formation in Megagametophytes of Marsilea in Response to Growth Substances

1972 ◽  
Vol 62 (1) ◽  
pp. 24
Author(s):  
William W. Bloom ◽  
Kenneth E. Nichols
Keyword(s):  
Growth Substances ◽  
Rhizoid Formation

scholarly journals THE EFFECT OF UNILATERAL ULTRAVIOLET LIGHT ON THE DEVELOPMENT OF THE FUCUS EGG

1941 ◽  
Vol 24 (3) ◽  
pp. 263-278 ◽  
Author(s):  
D. M. Whitaker
Keyword(s):  
Ultraviolet Light ◽  
Wave Length ◽  
Single Layer ◽  
The Other ◽  
Maximum Response ◽  
Strong Response ◽  
Wide Range ◽  
The Difference ◽  
Adequate Dosage ◽  
Rhizoid Formation

1. When Fucus eggs which have been fertilized for a sufficient length of time are irradiated unilaterally with monochromatic ultraviolet light (λ2804 Å) of adequate dosage, 97–100 per cent form rhizoids on the halves of the eggs away from the source of radiation (see Figs. 1 and 2). 2. The responsiveness of the eggs increases gradually after fertilization and does not reach a maximum until about 7 hours at 15°C. (see Fig. 3). The first rhizoids begin to form in a population at about 12 hours after fertilization. The responsiveness remains maximal until at least 11 hours after fertilization. 3. It is suggested that the low responsiveness of a population of eggs at an earlier period is due to recovery from the effects of irradiation before the rhizoids begin to form. 4. The response of eggs to λ2804 Å is proportional, over a wide range, to the logarithm of the dosage (see Fig. 1). Dosage was regulated by the duration of exposure during the period of maximum response. 5. High dosages of λ2804 Å, of the order of 10,000 ergs per mm.2, cause the rhizoids to form fairly precisely away from the source of radiation (see Fig. 2). Twice this dosage inhibits rhizoid formation altogether without causing cytolysis. 6. Other wave-lengths which have also been shown to be effective are: 3660, 3130, 2654, 2537, 2482, and 2345 Å. Only exploratory measurements have been made to test the effectiveness of these wave-lengths, but they show that much greater energy is necessary to obtain a strong response with λ3130 and 3660 Å, especially the latter. The wave-lengths shorter than 2804 Å, on the other hand, show the same order of effectiveness as λ2804 Å. Some may be more effective. 7. A beam of λ2804 Å which is incident on a single layer of Fucus eggs is completely extinguished at 2, 3, 6, or 6½ hours after fertilization. About 85 per cent of a beam of λ3660 Å is extinguished. The wave-length 3660 Å is thus not so completely absorbed as λ2804 Å, but the difference in proportion absorbed by the egg is not nearly so great as the difference in effectiveness.

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