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Enamel cover of the mammalian teeth: structural, functional, developmental and phylogenetic aspects.
Hanousková, Pavla ; Horáček, Ivan (advisor) ; Němec, Pavel (referee)
Specificities of the mammalian teeth and their enamel coat with particular re- spect to the autapomorphies establishing the mammalian organization. Basic structural and organizational levels of the enamel histology (nanocrystals, elementary crystallites, prismatic enamel, IPM, schmelzmuster, ultimate characteristics of particular dentitions). Basic survey of comparative data: characterization of enamel of mammals in particular clades and a brief summary of their specificities. Concluding remarks on current state of knowledge and per- spectives of further study. 1
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Magnetic orientation in mammals
Tejmlová, Kristýna ; Němec, Pavel (advisor) ; Vácha, Martin (referee)
Earth's magnetic field can provide animal with both directional and positional information. The ability to perceive and utilize information extracted from the geomagnetic field is called magnetoreception. Magnetoreception mechanisms remain largely unknown. Three main hypotheses are currently supported by experimental evidence. The light-independent mechanisms are based either on electromagnetic induction or on biogenic magnetite. The light-dependent mechanism is based on specific chemical reaction between radical pairs. Perception of the geomagnetic field facilitates both long- and short-distance orientation of animals. Some animals exhibit the magnetic alignment, i.e., spontaneuos preference for a certain geomagnetic direction. Another manifestation of magnetoreception is magnetic compass (polarity- or inclination-based, depending on species), which enable an animal to determine the azimuth, i.e., the angle between the direction of motion and geomagnetic field vector. Magnetic map sense enable an animal to determine its position and direction to the goal destination, most likely utilizing the inclination and the intensity of the geomagnetic field as navigational cues. Magnetic orientation of mammals seems to be a widespread phenomenon. Light- independend, polarity compass has been reported in...
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Metabolism of uric acid during mammalian evolution
Mančíková, Andrea ; Krylov, Vladimír (advisor) ; Stibůrková, Blanka (referee)
Uric acid is the end product of purine metabolism of humans and some higher primates. In other mammals enzyme urate oxidase is capable to further convert uric acid to allantoin. During evolution of primates several mutations in urate oxidase gene had occured, led the enzyme to decrease its activity or to complete loss of function. What was the initial impetus for the utilization of uric acid and what biochemical traits of uric acid led to a tendency to retain a major of this metabolite production in the bloodstream? Uric acid has antioxidant capabilities and it is scavanger of free radicals. Increased levels of uric acid in blood has an effect on acute and chronic elevations of blood pressure. It is possible that hyperuricemia helped to maintain blood pressure under low-salt dietary conditions of primates during the Miocene. This mechanism probably have allowed to stabilize bipedalism our ancestors. Uric acid has an important role as a neuroprotector. As inhibitor the permeability blood-brain barrier, uric acid limits the infiltration of undesirable substances to the neurons and prevents central nervous system against the formation of inflammatory diseases. Such as neurodegenerative diseases may be caused by reduced serum uric acid levels. Uric acid protects against peroxinitrite damage tissues in the...
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Cryptids
Dvořáková, Dana ; Turek, Filip (referee) ; Sterec, Pavel (advisor)
Cryptids, video which is studying animals, its shapes, moves and the environment , where they find themselves. The video is looking equal to all entity without any difference, document varied life as same as passing death or rot as well. It also speaks about collaboration and the microworld, which creates perfect unit. Silent mutual conversations.
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Analysis of trade in some groups of mammals protected by the CITES convention between the EU and third countries
KUCÍRKOVÁ, Kateřina
Unsustainable international wildlife trade together with destruction and pollution of wild nature and spread of the invasive species, has long been recognised as a major threat to biodiversity. The subject of this thesis is an evaluation of international trade with some groups of mammals (Great apes and Rhinos) covered by CITES convention between European Union and third countries according EU Annual Reports in 2000 ? 2009. The trade has been divided into export and import and within these categories were evaluated main traded species, types of specimens, exporter and importer, source and purpose of the trade. It was found the trends of Great apes export and import increased, trend of Rhinos export decreased, the trend of Rhinos import increased over this period.
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CLASSIFICATION OF STATEMENT OF WASTEPOND MAPE THROUGH THE USE OF THE CHOSEN MARKERS OF BACKGROUND
HULANOVÁ, Monika
The main point of the bachelor´ s writing was to analyse the stand of wastepond after the mining uranic ores. This analysis was attached by chosen indicators of the background. Little land mammals were chosen as an indicator. The samples were gained through trapping to the collapsible traps and then they were stored in the freezer. The gathered material was sent for the analysis of the chosen microelements (As, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Zn). The analysis was provided by ANECLAB s.r.o. in České Budějovice. Next the problem of rescue and recultivation of watched landscape was analysed. The accomplishments of working describe the stand of the wastepond DIAMO s.p. in light of ecological stability of the formation in the landscape and the influence of recultivation on the surrounding watched biota and consequential comprehension of the areas to the landscape.
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