Amphibians tadpoles

Immunotoxic Effects of Environmental Chemicals on Amphibian Tadpoles... 

Tavera-Mendoza L, Ruby S, Brousseau P, Fournier M, Cyr D, Marcogliese, D (2002a) Response of the amphibian tadpole (Xenopus laevis) to atrazine during sexual differentiation of the testis. Environ Toxicol Chem 21 527-531... 

Ralph S, Petras M. 1998. Caged amphibian tadpoles and in situ genotoxicity monitoring of aquatic environments with the alkaline single cell gel electrophoresis (comet) assay. Mutat Res 413 235-250. 

Many organisms rely on anti-predator defenses after contact with a predator (Brodie, Formanowicz Brodie, 1991). Because energetic costs and mortality risks are increased during contact, some species avoid these interactions whenever possible. A number of animals chemically detect and avoid predators, including invertebrates (Parker Shulman, 1986 Alexander Covich, 1991 Turner, 1996), fish (Keefe, 1992 Smith, 1992 Mathis Smith, 1993), reptiles (Thoen, Bauwens Verheyen, 1986 Dial, 1989 Cooper, 1990), and mammals (Weldon, 1990). In anuran amphibians, tadpoles commonly avoid the waterborne odors of predators (Petranka, Kats Sih, 1987 Flowers Graves, 1997 Kie-secker, Chi vers Blaustein, 1997), and among caudate amphibians, both larval and adult... 

Reaction of pigmentary system of amphibian tadpoles in lower concentrations of some pesticides. In Ib-oblems of ecological monitoring and ecosystem model. L. Gidmeteoizdat. T. VI. pp. 77-90. (Russ.). 

The amphibian metamorphosis test is based on the abiUty of thyroid hormones to induce precocious transformation of a tadpole into a frog or of the axolod into a salamander. It is rarely used because of solubiUty problems and the difficulty of applying the results to humans. 

Pauli, B.D., Coulson, D.R., BerriE, M. (1999) Sensitivity of Amphibian Embryos and Tadpoles to Mimic 240 LV Insecticide Following Single or Double Exposures. Environmental Toxicology and... 

In the OE of jawed fish only cellular, and little if any, tissue specialisation is achieved. During metamorphosis from tadpole to adult in amphibia, a developmental parallel of water-to-land transition includes the timing of maturation of the AOS. The system as it appears in living amphibians, is already a more or less discrete entity (Fig. 4.3) with its own sub-set of receptors. A process of regionalisation within the bulb, already underway even at the level of organisation in cartilaginous fishes, shows parallel adjustments (Dryer and Graziadei, 1993). 

Amphibians Bullfrog, Rana catesbeiana tadpoles South Carolina ... 

Greulich, K., Hoque, E., and Pflugmacher, S., Uptake, metabolism, and effects on detoxication enzymes of isoproturon in spawn and tadpoles of amphibians, Ecotoxicol. Environ. Saf., 52, 256, 2002. 

Benbassat J (1974) The transition from tadpole to frog haemoglobin during natural amphibian metamorphosis. I. Protein synthesis by peripheral blood cells in vitro. J Cell Sci 15 347-357... 

These hormones induce amphibian metamorphosis, the change of a tadpole into a frog—an obviously very complex series of biochemical and developmental reactions. Human fetuses will show skeletal abnormalities as well as neuromuscular and mental retardation if born with an inadequately functioning thyroid gland. 

As aquatic animals, tadpoles can use diffusion and dilution to remove excess ammonia, but the amphibian frog excretes urea. Birds and some reptiles excrete uric acid. In most mammals, excess ammonia is excreted as urea. 

Metamorphosis differs in the many different amphibian species. In frog development, the eggs hatch and give rise to tadpoles, small aquatic larvae that have exter-... 

Gutleb AC, Appelman J, Bronkhorst MC, et al. 1999. Delayed effects of pre- and early-Ufe time exposure to polychlorinated biphenyls on tadpoles of two amphibian species (xenopus laevis and rana temporaria). Environ Toxicol Pharmacol 8 1-14. 

In amphibians, the dark coloration in eggs and tadpoles is chiefly accredited to... 

For the littoral zone, tadpoles, frogs, salamanders and other amphibians are also typical, and there may be some reptiles (snakes and tortoises). 

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