Interaction Between the Effects of pH and Density on Growth and Development in Rana Temporaria L. Tadpoles

1989 ◽  
Vol 3 (1) ◽  
pp. 45 ◽  
Author(s):  
C. P. Cummins
Keyword(s):  
Growth And Development ◽  
Rana Temporaria ◽  
Effects Of Ph

Thyroid growth and its relationship to metamorphosis in Rana temporaria

Development ◽  
1966 ◽  
Vol 16 (3) ◽  
pp. 487-496
Author(s):  
Harold Fox
Keyword(s):  
Thyroid Gland ◽  
Growth And Development ◽  
Maximum Rate ◽  
Cellular Proliferation ◽  
Rana Temporaria ◽  
Thyroid Cells ◽  
Metamorphic Climax

In a previous work on pronephric degeneration, larvae of Rana temporaria from practically the whole range of the metamorphic cycle were studied (Fox, 1962). Metamorphosis in anurans is dependent upon the presence of a functional thyroid gland (Kollros, 1951; Lynn & Wachowski, 1951; Etkin, 1964), and the same specimens have now been used to investigate thyroid growth and development quantitatively and qualitatively, especially in relation to those major events which occur at the metamorphic climax between stages 49 and 54 (Cambar & Marrot, 1954). It will be shown that in larvae from 16 mm long (stage 41; see Fox, 1962) until practically the end of the climax (stage > 53), thyroid cells are of stable volume (about 700 μ3), and thyroid enlargement is by cellular proliferation and vesicular expansion. The maximum rate of thyroid growth occurs between 16 mm and 28 mm (stages 41–45).

Effects of pH on K depolarization and contracture in frog muscles

1979 ◽  
Vol 57 (2) ◽  
pp. 217-219
Author(s):  
Hrvoje Lorković
Keyword(s):  
Rana Temporaria ◽  
Rana Esculenta ◽  
Low Ph ◽  
Fiber Bundles ◽  
Bathing Solution ◽  
Mechanical Tension ◽  
Contraction Coupling ◽  
High K ◽  
Frog Species ◽  
Effects Of Ph

Membrane potential changes and mechanical tension provoked by 20 or 80 mM K at pH 8.0 or 4.5 were measured in muscle fiber bundles from Rana temporaria and Rana esculenta. The bathing solution contained Cl as the main anion. Low pH increased the depolarizing efficiency of high K to about the same degree in muscles of both species of frogs. The tension–[K] relationship was shifted toward lower [K] in muscles from R. temporaria and toward higher [K] in muscles from R. esculenta. It was concluded that the depolarization–contraction coupling was insensitive to pH changes in the former but not in the latter frog species.

scholarly journals The Effects of pH-Neutral Electrolysed Oxidising Water on Growth and Development of Chrysanthemums

Agricultura ◽  
2021 ◽  
Vol 18 (1-2) ◽  
pp. 9-15
Author(s):  
Andrej Šušek ◽  
Klara Copot ◽  
Metka Šiško
Keyword(s):  
Growth And Development ◽  
Cut Flower ◽  
Cut Flowers ◽  
Aboveground Part ◽  
Effects Of Ph ◽  
Water Ph ◽  
Test Plants

The aim of the study was to analyse the effects of pH-neutral electrolysed oxidising water (pH-neutral EOW), prepared by using the Envirolyte® system, on the growth and development of chrysanthemums. The experiment included two varieties of potted ('Tonka Blanc', 'Jahou CoCo') and two cut flower varieties of chrysanthemums ('Annecy White', 'Ninja'). The test plants planted in pots were irrigated with three different solutions of pH-neutral EOW (0%, 0.1% and 0.2%). Based on the results of the study, we can confirm that pH-neutral EOW has a significant effect on the growth and development of the studied chrysanthemum varieties. In potted chrysanthemums, we found a significant effect on the increased number and diameter of inflorescences, as well as fresh and dried weight of the plant and inflorescences. Chrysanthemums for cut flowers were taller and more developed, with a greater weight of the aboveground part of the plant. Its effect on the growth and development of the studied varieties depended on the solution of the mixture. Best results were observed with the 0.2% solution of pH-neutral EOW.

An ultrastructural study of vegetative incompatibility in plants

1978 ◽  
Vol 36 (2) ◽  
pp. 436-437
Author(s):  
Randy Moore
Keyword(s):  
Ultrastructural Study ◽  
Cell Walls ◽  
Growth And Development ◽  
Solanum Pennellii ◽  
Initial Product ◽  
Basic Aspect ◽  
Tissue Interactions ◽  
Graft Interface ◽  
Antigen Antibody ◽  
Standard Fixation

Cell and tissue interactions are a basic aspect of eukaryotic growth and development. While cell-to-cell interactions involving recognition and incompatibility have been studied extensively in animals, there is no known antigen-antibody reaction in plants and the recognition mechanisms operating in plant grafts have been virtually neglected.An ultrastructural study of the Sedum telephoides/Solanum pennellii graft was undertaken to define possible mechanisms of plant graft incompatibility. Grafts were surgically dissected from greenhouse grown plants at various times over 1-4 weeks and prepared for EM employing variations in the standard fixation and embedding procedure. Stock and scion adhere within 6 days after grafting. Following progressive cell senescence in both Sedum and Solanum, the graft interface appears as a band of 8-11 crushed cells after 2 weeks (Fig. 1, I). Trapped between the buckled cell walls are densely staining cytoplasmic remnants and residual starch grains, an initial product of wound reactions in plants.

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