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Orientation of helminths during host seeking
Vojtová, Terezie ; Mikeš, Libor (advisor) ; Horák, Petr (referee)
The parasitic helminths are often forced in the environment to search for their host quickly in order to continue the ontogenetic development, or else to finish it. To search for and indentify the host, they use various types of receptors which allow them to provoke a taxes corresponding to the oncoming stimulus and to react regarding the current situation. In respect to the concept relevant to the helminths, this work concerns trematodes, whose freely movable stadia are miracidium and cercacia, and then monogeneans which are viparous or oviparous with oncomiracidium larva, and nematodes during which the third larva stage moves. The representatives of the groups of Myxozoans and Ciliophorea are also mentionned, since they use similar mechanisms to look for hosts as helminths. This thesis includes the summary of the existing knowledge related to the orientation of helminths in the environment. On the basis of the data that is already known, it is possible to compare which mechanisms are used for host-seeking by particular species, and according to which signals from the surroundings they most often orientate themselves. Powered by TCPDF (www.tcpdf.org)
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Orientation of helminths during host seeking
Vojtová, Terezie ; Mikeš, Libor (advisor) ; Horák, Petr (referee)
Helminths are often forced in the environment to search for their host quickly in order to continue the ontogenetic development, or else to finish it. To search for and indentify the host, they use various types of receptors which allow them to provoke a taxes corresponding to the oncoming stimulus and to react to the presence of the host. This thesis includes the summary of the existing knowledge related to the orientation of helminths, the comparison of the mechanisms used by the searching of a host and signals in the environment. In respect to the concept relevant to the helminths, this work concerns trematodes, whose freely movable stadia are miracidium and cercaria, and then monogeneans which are viparous or oviparous with oncomiracidium larva, and nematodes with the third infective larva stage. The representatives of fish parasites of Myxozoans and Ciliophorea are also mentionned, since they use similar mechanisms to look for hosts as helminths. Powered by TCPDF (www.tcpdf.org)
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