Effects of aluminium and low pH on growth and development in Rana temporaria tadpoles

Oecologia ◽  
1986 ◽  
Vol 69 (2) ◽  
pp. 248-252 ◽  
Author(s):  
C. P. Cummins
Keyword(s):  
Growth And Development ◽  
Rana Temporaria ◽  
Low Ph

The Effects of Low pH and Aluminum on Breeding Success in the Frog Rana temporaria

1992 ◽  
Vol 26 (4) ◽  
pp. 353 ◽  
Author(s):  
Robert C. Beattie ◽  
Richard Tyler-Jones
Keyword(s):  
Breeding Success ◽  
Rana Temporaria ◽  
Low Ph ◽  
Frog Rana Temporaria

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.

The Mobilization of the Calcium Carbonate Deposits in the Endolymphatic Sacs of Metamorphosing Frogs

1966 ◽  
Vol 45 (2) ◽  
pp. 329-341
Author(s):  
J. B. PILKINGTON ◽  
K. SIMKISS
Keyword(s):  
Calcium Carbonate ◽  
Rana Temporaria ◽  
Morphological Changes ◽  
Environmental Water ◽  
Low Ph ◽  
The Other ◽  
Biochemical Data ◽  
Calcium Salts ◽  
Metamorphic Climax ◽  
Carbonate Deposits

1. Tadpoles of Rana temporaria have been reared in solutions of high and low pH with and without calcium. 2. Methods have been devised for analysing calcium, carbonate and phosphate in individual tadpoles. From these analyses it is possible to determine the distribution of calcium salts between the endolymphatic sacs and the skeleton throughout metamorphosis. 3. A system has been devised for correlating biochemical data with the morphological changes occurring during metamorphosis by means of a scale of ‘developmental days’. 4. The resorption of the endolymphatic deposits is not influenced by the acidity of the environmental solution. 5. Tadpoles reared in solutions containing added calcium had at any one stage in metamorphosis a larger reserve of endolymphatic calcium and a better ossified skeleton than the other tadpoles. 6. During metamorphic climax, when the tadpoles do not feed, the calcareous material in the endolymphatic sac is resorbed to provide calcium for the ossification of the skeleton and to make good any renal loss of calcium. 7. The resorption of endolymphatic calcium carbonate occurs in all tadpoles during metamorphic climax irrespective of the level of calcium in the environmental water. 8. The otoliths do not appear to be resorbed and the spinal portion of the deposits in the endolymphatic sacs may be more labile than those in the cranial regions.

Relationship between golgi apparatus and axonal reticulum in sympathetic ganglion cells

1978 ◽  
Vol 36 (2) ◽  
pp. 598-599
Author(s):  
J. Quatacker ◽  
W. De Potter
Keyword(s):  
Golgi Apparatus ◽  
Sympathetic Ganglion ◽  
Phosphotungstic Acid ◽  
Ganglion Cells ◽  
Low Ph ◽  
Dense Core ◽  
Dense Core Vesicles ◽  
Large Dense Core Vesicles ◽  
Cervical Ganglia ◽  
Axoplasmic Reticulum

Mucopolysaccharides have been demonstrated biochemically in catecholamine-containing subcellular particles in different rat, cat and ox tissues. As catecholamine-containing granules seem to arise from the Golgi apparatus and some also from the axoplasmic reticulum we examined wether carbohydrate macromolecules could be detected in the small and large dense core vesicles and in structures related to them. To this purpose superior cervical ganglia and irises from rabbit and cat and coeliac ganglia and their axons from dog were subjected to the chromaffin reaction to show the distribution of catecholamine-containing granules. Some material was also embedded in glycolmethacrylate (GMA) and stained with phosphotungstic acid (PTA) at low pH for the detection of carbohydrate macromolecules.The chromaffin reaction in the perikarya reveals mainly large dense core vesicles, but in the axon hillock, the axons and the terminals, the small dense core vesicles are more prominent. In the axons the small granules are sometimes seen inside a reticular network (fig. 1).

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