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EN
Direct environmental impact and microevolutionary pressure may both shape the phenotype by acting synergistically (cogradient) or antagonistically (countergradient). An experimental approach is therefore needed to determine which environmental challenges are responsible for the observed inter-population variation in a phenotypic trait and if such variation is adaptive. Rana temporaria L. larvae were reared in a factorial experiment, with two temperature regimes (differential of 6[degrees]C) and larvae originating from two source populations in Poland: a montane pond in the Babia Gora National Park (elevation 1025 m) and a lowland swamp near Warszawa (elevation 100 m). Populations did not differ in early larval growth rates or in the length of the larval period. In both populations, the early rates of development were higher and the larval period was expectably and substantially shorter at higher temperature. The montane larvae were heavier at metamorphosis than the lowland larvae, but significantly so only at the low temperature treatment. The observed patterns of responses partially conform to the cogradient model of phenotypic variation, in which both environmental and selective effects are mutually enhancing the differentiation of populations.
EN
General metabolism and lead accumulalion was studied in common frog tad-poles irradiated with UV (UV-A of 0.24 kJ . m-2, UV-B of 2.7 kJ . m-2) during lead poisoning (1 mg/dm3 Pb2+) and during recovery after lead poiso-ning. General melabolism of larvae during lead poisoning ranged between 0.061 +- 0.004 and 0.079 +- 0.016 mg O2/g . h-1 and the differences between experimental groups were insignificant. Significanl differences occurred after the 24, 48 and 72 hours of recovery period after the Pb2+ poisoning. General metabolism of tadpoles exposed lo UV during recovery period after lead poisoning was increasing, after initial drop (0.059 +- 0.010 mg 02/g. h-1), reaching the highesl level of 0.192 +- 0.028 mg O2/g . h-1 after 72 h. The level of accumulated lead ranged from 0.305 +- 0.156 to 0.521 +- 0.263 mg/g d.m. UV did not influence significanlly on lead accumulation and removal.
PL
Zbadano metabolizm ogólny i poziom skumulowanego ołowiu u larw żaby trawnej naświetlanych promieniowaniem UV (UV-A - 0.24 kJ . m-2, UV-B - 2.7 kJ . m-2) w czasie zatruwania ołowiem (1 mg/dm3 Pb2+) i w okresie od-truwania. Larwy w czasie zatruwania ołowiem zużywały od 0.061 +- 0.004 do 0.079 +- 0.016 mg O2/g . h-1. Różnice pomiędzy poszczególnymi grupami nie były statystycznie istotne. Znaczące różnice zaobserwowano po 24, 48 i 72 godzinach odtruwania. Poziom metabolizmu ogólnego larw eksponowanych na UV w czasie odtruwania początkowo się obniżył (0.059 +- 0.010 mg O2/g . h-1), a następnie wzrósł osiągając największe wartości po 72 godzinach od-truwania (0.192 +- 0.028 mg O2/g . h-1). Badane larwy skumulowały od 0.305 +- 0.156 do 0.521 +- 0.263 mg/g s.m. ołowiu. Nie stwierdzono znaczącego wpływu UV na kumulację i usuwanie jonów ołowiu z organizmu badanych larw.
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