Results 201 to 210 of about 32,751 (228)

The effects of the herbicide atrazine on freshwater snails

Ecotoxicology, 2015
Atrazine has been shown to affect freshwater snails from the subcellular to community level. However, most studies have used different snail species, methods, endpoints, and atrazine exposure concentrations, resulting in some conflicting results and limiting our understanding.
Kyle D. Gustafson, Jason B. Belden, Matthew G. Bolek   +2 more
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Population genetics of freshwater snails

Trends in Ecology & Evolution, 1991
Freshwater snails have attracted the attention of biologists for a long time, because they are intermediate hosts of schistosomes, agents of bilharziases. However, population-genetic studies of freshwater snails have been undertaken only during the past decade, covering topics such as the relative roles of genetic drift and gene flow in subdivided ...
Bernard Delay, Philippe Jarne
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The maintenance of hybrids by parasitism in a freshwater snail

International Journal for Parasitology, 2014
Hybrids have often been labelled evolutionary dead-ends due to their lower fertility and viability. However, there is growing awareness that hybridisation between different species may play a constructive role in animal evolution as a means to create variability.
Frida Ben-Ami, Yonathan Guttel
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Haemoglobin producing cells in freshwater snails

Zeitschrift f�r Zellforschung und Mikroskopische Anatomie, 1972
One of the cell types occurring in the connective tissue of gastropods and bivalves is thepore cell. Cells of this type have a characteristic morphology in that their plasmamembrane has many invaginations bridged by cytoplasmic tongues. In the well developed granular endoplasmic reticulum and in these invaginations fine granular material, sometimes ...
Taede Sminia, H. H. Boer, Addy Niemantsverdriet   +2 more
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Monoamines and their metabolites in the freshwater snail Biomphalaria glabrata

Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, 2000
Metabolism of the major monoamines and their functions were studied in the freshwater snail Biomphalaria glabrata. In both juvenile and adult snails, the plasma (cell-free hemolymph) appears to act as a reservoir for most of these monoamines and their metabolites including among others, L-dopa and dopamine as major constituents.
Timothy P. Yoshino, Venkatachari Santhanagopalan   +1 more
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Biological methods for the control of freshwater snails

Parasitology Today, 1990
As a result of the advent of new drugs and diagnostic techniques, the emphasis in the control of schistosomiasis has changed from snail control to chemotherapy for infected individuals. However, chemotherapy does not prevent reinfection and there remains a need to reduce snail densities in human water supplies. In the past, treatment with molluscicides
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Chromosomes of Gyraulus circumstratius, a Freshwater Snail

Nature, 1960
POLYPLOIDY is relatively scarce in the animal kingdom, and is apparently almost entirely confined to those species in which reproduction is partheno-genetic, hermaphroditic or clonal1. Such animals usually do not have a heterogametous sex-determining mechanism to be disturbed by polyploidy.
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Freshwater snails in brackish water

1929
(Uploaded by Plazi from the Biodiversity Heritage Library) No abstract provided.
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Fixed phagocytes in the freshwater snail Lymnaea stagnalis

Cell and Tissue Research, 1979
Morphological and histochemical examination of the blood and connective tissue of the freshwater snail Lymnaea stagnalis injected with various types of foreign particulate materials has shown the existence of free as well as fixed phagocytic cells. The morphology of the fixed phagocytes is described, and the phagocytic system of the snail is compared ...
W. P. W. van der Knaap, F. G. M. Kroese, Taede Sminia   +2 more
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On the underwater weights of freshwater snails

Zeitschrift f�r Vergleichende Physiologie, 1963
1. Under laboratory conditions, the mantle cavities of Lymnaea stagnalis and Planorbarius corneus immediately after ventilation at the surface, contain enough air to make the animals buoyant. 2. Both species lose this buoyancy over the first three hours of submersion by a process reducing the gas volume. 3. The gas is used as
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