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Embryogenesis and early ontogenesis of basal versus derived groups of the Ray-finned fishes (Actinopterygii)
Truhlářová, Veronika ; Černý, Robert (advisor) ; Krylov, Vladimír (referee)
Almost 30 thousand species of the ray-finned fishes, which exist in the world today, represent approximately one half of all known vertebrates. The ray-finned fishes are divided into four distinct groups: bichirs, chondrosteans, neopterygians and teleost fishes. These groups differ significantly in their mode of embryogenesis, however, particular details are known only from few model species like danio or medaka, which all belong to the most diversified actinopterygian group, the teleost fishes. In this thesis, I summarize the current knowledge and compare the patterns of embryogenesis of all four groups of ray-finned fishes. Interestingly, their patterns of early ontogenesis are very dissimilar, such as bichirs and sturgeons undergo holoblastic cleavage of the whole egg, similar to amphibians, whereas teleost fishes evolved strictly meroblastic cleavage of the cytoplasm accumulated on the animal pole of yolk mass, which has profound effects on their further development. The meroblastic cleavage, which is described in details in zebrafish, serves as a template for studying early ontogenesis of all other teleost fishes comprising nearly 27 thousand species. The meroblastic cleavage remained preserved in all teleosts, aside from the fact that these fishes have developed many alternative reproductive...
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The evolution of vision in ray-finned fishes
Truhlářová, Veronika ; Musilová, Zuzana (advisor) ; Kalous, Lukáš (referee)
Vision plays a key role in life of many vertebrates, and the performance of visual system is often adapted to specific environments inhabited by individual species. Fish colonized a wide range of habitats and adjusted their visual abilities to maximize their success rates in hunting, reproduction and predator avoidance. This thesis is focused on molecular mechanism of visual system, namely on genes for photoreceptor proteins, opsins, of two major groups of teleost fishes: African riverine cichlids (family Cichlidae, order Cichliformes, part of larger taxa Percomorpha), and European freshwater cyprinids (family Cyprinidae, order Cypriniformes, part of larger taxa Ostariophysi). Two types of photoreceptor cells are present on retina: the cones and the rods. Actinopterygian fishes in general have four cone opsin types (SWS1, SWS2, RH2 and LWS) used for colour (photopic) vision, and one rod opsin type (rhodopsins) for vision in deteriorated light conditions (scotopic vision). In the present thesis, I focus on 1) DNA sequence and amino acid substitutions of the opsin genes, and on 2) gene expression levels of opsins sensitive to various wavelengths of light spectrum. The results of my work show that both cichlids (family Cichlidae) and cyprinids (family Cyprinidae) have a complete set of opsin genes in...
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Kronika o Štylfrýdovi" and "Kronika o Bruncvíkovi" - Comparing knightly story and the book of native reading
TRUHLÁŘOVÁ, Veronika
This diploma thesis is going to focus on a comparison of a traditional knight´s short story and an early modern folk reading of the Chronicles of "Štifríd" and "Bruncvík"; the focus will be primarily on differences of the two texts. Narratives in Czech literature were repeatedly used in different time periods and in texts of various genres: from the allegorical knight's short story in the end of the 14th century to the early modern funny book of folk reading or even e.g. a folclore fairytale in the 19th century. The starting point for the work will be, therefore, an introduction of the interpretation attempts aimed at the filliation of handwritten and printed editions of the two narratives (Jaroslav Kolár's study), then an actual composition of the work (Hana Mirvaldová - Šmahelová's study) and also an allegorical presentation (Jaroslav Kolár's story). The main part of the thesis is an analysis of the handwritten releases from the turn of the 14th and 15th century and the printed edition from the 18th century, and their mutual comparison.
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Embryogenesis and early ontogenesis of basal versus derived groups of the Ray-finned fishes (Actinopterygii)
Truhlářová, Veronika ; Černý, Robert (advisor) ; Krylov, Vladimír (referee)
Almost 30 thousand species of the ray-finned fishes, which exist in the world today, represent approximately one half of all known vertebrates. The ray-finned fishes are divided into four distinct groups: bichirs, chondrosteans, neopterygians and teleost fishes. These groups differ significantly in their mode of embryogenesis, however, particular details are known only from few model species like danio or medaka, which all belong to the most diversified actinopterygian group, the teleost fishes. In this thesis, I summarize the current knowledge and compare the patterns of embryogenesis of all four groups of ray-finned fishes. Interestingly, their patterns of early ontogenesis are very dissimilar, such as bichirs and sturgeons undergo holoblastic cleavage of the whole egg, similar to amphibians, whereas teleost fishes evolved strictly meroblastic cleavage of the cytoplasm accumulated on the animal pole of yolk mass, which has profound effects on their further development. The meroblastic cleavage, which is described in details in zebrafish, serves as a template for studying early ontogenesis of all other teleost fishes comprising nearly 27 thousand species. The meroblastic cleavage remained preserved in all teleosts, aside from the fact that these fishes have developed many alternative reproductive...
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Allegory of characters in The Labyrinth of the World and the Paradise of the Heart by Jan Amos Comenius
TRUHLÁŘOVÁ, Veronika
The topic of my thesis is the allegory of the characters in the Labyrinth of the World and Paradise of the Heart by Jan Amos Komensky. The best known of Comenius text has been subject to several interpretations conducted on various methodological positions (Philological - Critical, structuralist, thematic etc.) The basis of my work is thus to show existing interpretive trials relating to the composition of the work (treatise by Antonín Škarka and Lubomir Doležel) and allegorical depiction (study by J. B. Čapek and Hana Šmahelová) and their comparison. The focus of the work will be the analysis of key literary figures of the Labyrinth (The Pilgrim, Delusion and Ubiquitous) and their development. J. B. Čapek, Jan Lehár and Věra Vařejková were my main interpretation stimuli.
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