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Molluscs as a new model system in molecular biology
Ber, Tobiáš ; Svoboda, Petr (advisor) ; Pergner, Jiří (referee)
Molluscs form the second largest animal phylum and are of great biological and economic significance. Their distinct evolutionary adaptations enabled them to inhabit a broad range of environments, with many of them invading new areas and becoming invasive pest species. Despite their importance, molluscan model systems have not received attention they deserve. In this bachelor thesis, I have reviewed the current state of molluscan model systems in molecular biology and analyzed their significance for more common use. From available data, it is apparent that the already established molluscan models are either marine or fresh-water, and therefore require more complex logistics and maintenance in order to set up a laboratory culture. To remedy the problem of aquaculture, the use of terrestrial gastropods was proposed. Here, I suggest that gastropods genus Deroceras have a good potential to become a new prominent molluscan model system in molecular biology.
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Relationship between recent and Holocene mollusc fauna diversity of the Veľká Fatra Mts.
Kubíková, Kateřina ; Juřičková, Lucie (advisor) ; Horáček, Ivan (referee)
Quaternary molluscs assemblages are one of the most important sources of information used for palaeoecology and biogeography reconstructions, yet little attention has been paid to the informative value of quaternary profiles on a landscape spatial scale. In the area of Velka Fatra Mts., a large number of existing records concerning both recent and quaternary land snails enable us to compare Holocene and recent species diversity to estimate how many profiles are needed to evaluate species richness of such geomorphologically diverse area. In this study, available data are supplemented with samples from additional recent sites and quantitative analysis of material from quaternary profiles Stankovany and Skamenelá skala. In recent sites, 129 species of terrestrial molluscs were recorded (more than 72 % of land snail species occurring in Slovakia). Samples from all seven Holocene profiles yielded 93 species, covering more than 85 % of recent land snails diversity. On the other hand, only about 50 % of recent land snail species were recorded in a single profile, thus highlighting the importance of multiple profiles evaluation in palaeoecological studies.
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Production and elimination of superoxide radical in relation to the compatibility of snails and trematodes
Cibulková, Lucie ; Skála, Vladimír (advisor) ; Nývltová, Eva (referee)
Almost all trematodes use snails as the intermediate host in their life cycles. To survive within the host, they have to efficiently avoid defense reactions of its immune system. The most important effector cells, haemocytes, produce reactive oxygen species with the first molecule known as superoxide radical. Various snail species produce different levels of these radicals in relation to the compatibility with the invasive trematode species. The parasite decreases the levels of toxic radicals by using antioxidant enzymes including superoxide dismutase which catalyzes transformation of superoxide radical into hydrogen peroxide. This dismutation reaction is the first step during the oxidative burst and likely influences survival of trematodes within the host. Based on the current knowledge the production and elimination of superoxide radical in relation to the compatibility between snails and trematodes have been described thoroughly for a few models such as for example Biomphalaria glabrata-Schistosoma mansoni. However, this interaction appears to play a key role and, therefore, it deserves more attention in another models as well. Key words: trematodes, snails, compatibility, haemocytes, oxidative burst, antioxidant enzymes, superoxide dismutase, superoxide radical
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Larval Stages of Flukes (Platyhelmintes: Trematoda) in Secondary School Education
Šulcová, Hana ; Říhová, Dagmar (advisor) ; Podroužková, Štěpánka (referee)
The parasites are one of the most important factors that shape relationships in the nature. This thesis deals mainly with developmental stages of trematodes (Platyhelmintes: Trematoda), especially the cercariae of so-called Schistosomes and sporocysts of Leucochloridium paradoxum, as well as with and their intermediate host - freshwater snails. Introductory chapters are focused on general introduction into the topic, such as basic terminology or occurrence issue of trematodes (mainly schistosomes) in the world and in the Czech Republic. In order to determine larval stages of flukes and their morphological types, the research was conducted in four Prague localities with known presence of aquatic snails. Only in one site, Kunratická tůň Pond, the constant presence of echinostomous cercariae (and in lesser extent also furcocercariae) in Radix labiata was recorded during summer season of 2015. In small pond in the Botanical Garden of the Natural Sciences Faculty of Charles University and in Modřanské tůně Ponds, xiphidocercarie in Lymnaea stagnalis were found. No cercarie were detected in the pond in the Genetic garden of Charles University. The presence of Leucochloridium paradoxum in the European Amber Snail Succinea putris was confirmed in the vicinity of Modřanské tůně Ponds. The verified...
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The influence of geology to the diversity of molluscan assemblages
Krajinčáková, Lucie Linda ; Juřičková, Lucie (advisor) ; Myšák, Jan (referee)
Molluscan populations are influenced by various factors of environment where they occur. In my work I am taking particular atention of soil properties, which are directly influenced by the geological substrate, and of course other factors which are with soil properties either directly or indirectly related. The important benchmarks are especially moisture, pH, calcium content and vegetation cover. This bachelor thesis also deals with utilization of calcium salts. Geological substrate is closely linked with the diversity and abundance of molluscan populations. Various pedochemical factors affect molluscan communities whether it is the amount of calcium in the soil or a pH value. In the past different authors found different dependencies between environmental factors, species composition and diversity of molluscan communities. Most of the studies were focused on very specific habitats and locations. In this thesis I tried to organize our knowledge about the specific effects of various environmental factors, especialy compositíon of geological substrate on malakofauna. Key words: Mollusca, Gastropoda, Geological substrate, diversity
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Molluscs of Boulder Sites in Křivoklátsko PLA and Their Use in Education
Kebert, Tomáš
The work deals with molluscs as specific inhabitants of boulder sites in southern part of Křivoklátsko PLA. It discusses related questions and information sources connected with nature protection. The thesis describes molluscs as generally lesser known, but diverse group of animals with variety of ecological requirements. It shows the results of malacozoological site research performed using collection of leaf litter samples and compares them to previous works. It also examines how the topic could be incorporated in education. The work emphasizes the ecology of molluscs, whose knowledge can facilitate contextual thinking about various organisms and also is not confined to a narrow scope of biology. The thesis discusses various means of education and describes a general proposal of excursion to the place of interest. Keywords gastropods ecology excursion nature protection didactics
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Gastropods, trees, pH, subsoil and epiphytic lichens
Pelant, Filip ; Svoboda, David (advisor) ; Peksa, Ondřej (referee)
Epiphytic lichens are under considerable grazing pressure due to invertebrate lichenivores, mostly gastropods. Preferences of tree-climbing gastropods affect vertical distribution of lichens, their habitat preferences and whole area of distribution. Higher grazing pressure is expected on sites with basic subsoil and sufficient sources of calcium, where the abundance of gastropods is higher. Most of researches about the topic of grazing pressure were therefore conducted on such sites, although this hypothesis has never been formally tested. Epiphytic communities are also affected by pH and other properties specific to its photophyte. Nevertheless, it is not known, if the same applies for grazing gastropods and how is the grazing pressure affected by tree species. I have addressed these questions in my thesis. I set an 80-days-long field transplantation experiment in the mixed forest of Moravský kras (South Moravia, Czech Republic). Glass fiber meshes with lichen thalli were placed on sixty trunks of three tree species (Carpinus betulus - hornbeam, Abies alba - fir, Fagus sylvatica - common beech) on both calcareous (limestone) and acidic (granodiorite) sites. Abundance and diversity of gastropods were measured. Determined grazing pressure was higher than pressure detected by other authors and was...
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Fauna nepôvodných bezstavovcov tropických skleníkov botanických a zoologických záhrad sveta a Českej republiky - review
Pažitková, Petronela
The following bachelor thesis with the topic: ,,Non-native invertebrate fauna of tropical and subtropical greenhouses in botanical and zoological gardens of the world and Czech Republic – review“ is concentrating on summarization of found researches, parrticularly in Czech and Slovak Republic, after that their brief comparison with some european and other countries of the world. The thesis is divided into four main sections. In the first section is a further explanation of basic concepts related to our thesis and a short characteristics of the most significant invertebrate groups. The following section is focused on the surveys that were done in botanical and zoological gardens mainly in Czechia and Slovakia, in short, foreign researches are also mentioned. Additionally, the following section is devoted on the measures againts the invasions and it also asks a question, if these species may be somehow useful. In the last section, we have compared these surveys with each other. We can observe a regularity of the occurence of some species, or on the other side, rare findings within the regions.
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Molluscs of Boulder Sites in Křivoklátsko PLA and Their Use in Education
Kebert, Tomáš
The work deals with molluscs as specific inhabitants of boulder sites in southern part of Křivoklátsko PLA. It discusses related questions and information sources connected with nature protection. The thesis describes molluscs as generally lesser known, but diverse group of animals with variety of ecological requirements. It shows the results of malacozoological site research performed using collection of leaf litter samples and compares them to previous works. It also examines how the topic could be incorporated in education. The work emphasizes the ecology of molluscs, whose knowledge can facilitate contextual thinking about various organisms and also is not confined to a narrow scope of biology. The thesis discusses various means of education and describes a general proposal of excursion to the place of interest. Keywords gastropods ecology excursion nature protection didactics
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Phylogenetic and ecological impact to the microstructures of mollusc shells
Nedvědová, Jana ; Juřičková, Lucie (advisor) ; Simon, Ondřej (referee)
This bachelor thesis summarizes the available information on microstructures of mollusc shells. The aim was to provide an overview of the different types of microstructures for specific specimens from different environments, as well as to obtain as much information as possible about the ecology of these animals. The first part summarizes the basic information on the shell formation. The following chapter summarizes known microstructure types of mollusc shells. Microstructures of molluscs living in terrestric, freshwater and marine environment are discussed. The influence of temperature changes on the shell microstructure of V. viviparus, the occurrence of vaterit within C. fluminea shells, the extreme environment of hydrothermal vents and cold seeps, as well as extreme temperatures on rocky shores, have been mentioned in more detail. The microstructures of related molluscs are compared with regard to ecology to determine whether the occurrence of microstructures in a particular group is given by the phylogeny of these animals, or if the changes in microstructures can be affected by different ecology. Key words: microstructures, molluscs shells, impact of phylogeny, impact of ecology, calcium carbonate, Mollusca, gastropods, bivalves
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