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Genetická diverzita zástupců rodu Ceropegia L.
Valová, Radmila
The genus Ceropegia was described by Carl Linnaeus and it is currently included in the family Apocynaceae. Representatives of Ceropegia are in many cases characterized by a succulent or climbing stem and flowers with an often tubular elongated crown. They grow mainly in tropical regions of the world, which represent for example India, the southern region of China, Africa and the Philippines. In this work, eight representatives of the genus Ceropegia were analyzed on the basis of nuclear and chloroplast regions of DNA, which function as a recognition site (marker) for their inclusion in the current system of the genus. All samples for analysis were get in dried form. For successful analysis, it was necessary to make methods such as isolating DNA, PCR, and DNA sequencing that produced sequences which, after modifications, were used to assign individual samples to an existing phylogenetic tree.
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Molekulární fylogeneze a adaptace rostlin na podmínky sucha
Petrová, Silvie
Due to the alternation of the dry season with the rainy season, the succulent plants gradually evolved to such conditions and thus gained evolutionary advantages over other plants for survival in these unwelcoming areas. The theoretical part of this thesis focuses on the occurrence of succulent plants and their CAM metabolism. Furthermore, the theoretical part deals with the field of molecular phylogenetics as an important discipline in phylogenetics including DNA sequencing. The experimental part of the work focuses on samples of selected species from the section of Echidnopsis from the Apocynaceae family. It also demonstrates the usage of DNA sequencing, work with bioinformatic softwares like Geneious version 8.1.9 and MEGA X version 10.2.4 and construction of phylogenetic trees including usage in phylogenetic analysis.
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Ontogeneze versus věk u břízy bělokoré (Betula pendula Roth)
Čadová, Barbora
Ontogenesis and age are an inseparable part of every living organism, including trees. During their life, trees are undergoing changes in external and internal structure. The ontogeny is related to aging, which is in every tree different. Some trees are aging faster others slower. Raimbault (2006) in his methodology divided stages of ontogeny into 10 parts and completed a rough estimate of age. This thesis is focused on this methodology and deals with the 7th stage of ontogeny in silver birches (Betula pendula Roth.), which grow at two different sites. At the site with unsuitable conditions for growth and at the site with optimal conditions for the growth of trees. This work compares environment in which the birch trees grow, their age and overall appearance.
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The genus Neotinea Rchb.f. in Europe
Vavřina, Štěpán ; Chumová, Zuzana (advisor) ; Vosolsobě, Stanislav (referee)
The thesis deals with the genus Neotinea from the phylogenetic, molecular and ecologic points of view. Most of its species have been classified in the genus Orchis until the use of molecular methods. Within the Orchidoideae, Neotinea forms a sister clade to the genera Anacamptis, Serapias, Ophrys and Himantoglossum. Six species are accepted now. The current taxonomic circumscription calls for a revision under the influence of new knowledge. Especially in N. tridentata, which contains several well-differentiated lineages and is the ancestor of the tetraploid N. commutata. Also the relationship between N. lactea and N. conica remains unresolved. The genome size within the genus ranges from 6.48 pg in N. maculata to 31.14 pg in N. lactea. All species except N. commutata, whose tetraploid origin is debated, are diploid (2n = 42). Partial endoreplication is present in the genus. The range of endoreplicated DNA is relatively narrow regardless of differences in genome size. Species prefer open, slightly basic habitats. In mycorrhizal interactions they appear generalistic with a preference for Ceratobasidiaceae. At the level of reproductive strategies, the genus Neotinea prefers the generative mode over the vegetative one. N. maculata is autogamous, the other species are allogamous, food deceptive, with...
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Biology and ecological dynamics of Baltic Fucus belts
Kivader, Martin ; Neustupa, Jiří (advisor) ; Němcová, Yvonne (referee)
The belt-forming algae of the genus Fucus are key species of the otherwise species-poor Baltic Sea. The distribution of the Fucus species is limited by the reduced salinity of brackish water to which the Baltic populations have adapted. The genus Fucus is known for high phenotypic plasticity and the absence of reproductive barriers, complicating the study of its recent radiation. The recent speciacion of the Baltic endemic F. radicans from locally adapted F. vesiculosus populations probably happened twice independenly 2 500-400 years ago. Baltic Sea is the largest brackish ecosystem characterised by a pronounced salinity gradient ranging from 1.2 to 30.2 ‰. It is influenced by the discharge of over 200 rivers and water exchange with the ocean is limited by the shallow Danish Straits. Since 1970s, Fucus decline and local extinction due to eutrophication of the Baltic Sea have been reported. Baltic water has high residence time which leads to accumulation of nutrients. In 1974, Helsinki Commission was established and the Helsinki Convention on the protection of the Baltic Sea Area was signed in response to its worsening state. Fucus belts, however, continue to decline and their ability for recovery is limited. Increased sedimentation due to eutrophication has in many locations resulted in the loss of...
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Streptophytic Algae with a Focus on the Class Zygnematophyceae
Špička, Jan ; Soldán, Zdeněk (advisor) ; Ráček, Jan (referee)
This bachelor's thesis deals with streptophyte algae, with special attention given to the class Zygnematophyceae. The thesis is written as a literature review, aiming to summarize existing knowledge about streptophyte algae, particularly focusing on the class Zygnematophyceae. Additionally, the thesis elucidates the phylogenetic relationships within this group, which historically have been challenging. The thesis primarily focuses on the description, ecology, and taxonomy of streptophyte lineages, emphasizing their significance in the study of terrestrialization, or the colonization of land. A significant part of this thesis is therefore to highlight the ecological and evolutionary role of streptophyte algae, especially in the context of their adaptation to terrestrial environments. An additional aim of the thesis is to address the issues associated with the group of algae, given their inconsistent definition. The thesis points out that algae do not form a monophyletic group, as they encompass various taxonomic lineages. This thesis can serve as a foundation for further research in the field of algology, thereby contributing to a better understanding and orientation in the process of terrestrialization. It also indicates the need for more phylogenetic studies to enhance understanding of the...
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Host Specialization and Evolution of Cuckoo Behavior in Bees
Policarová, Jana ; Straka, Jakub (advisor) ; Orr, Michael Christopher (referee) ; Litman, Jessica (referee)
Cuckoo bees are nest parasites of solitary and sometimes also social bee species. They do not build their own nests. Nor do they provision their larvae. Instead, they seek out a suitable host nest to lay their eggs in, and their larvae then feed on the host's provisions. In this doctoral thesis, I examined the host specialization of cuckoo bee species. I focused on the evolution of host specialization of cuckoo bees and factors which may limit their host choice - specifically whether and how are cuckoo bees affected by host food specialization. Answering these questions required phylogenetic reconstruction of several cuckoo bee lineages. We produced the first phylogenetic reconstruction of the tribe Sphecodini (Halictidae) and revised the taxonomy of the lineages Neolarrini, Biastini and Townsendiellini (Apidae), merging them into a single tribe Neolarrini. Lastly, we reconstructed the phylogeny of the mainly Palaearctic species of the genus Nomada, on the basis of which we divided the Nomada species into 13 subgenera. The mapping of ancestral character states showed that cuckoo bees of the genus Sphecodes change hosts quite frequently during evolution and are able to switch to phylogenetically distant hosts from different families. It also appears that there is no evolutionary trend towards...
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Detection of Correlated Mutations
Ižák, Tomáš ; Bendl, Jaroslav (referee) ; Martínek, Tomáš (advisor)
Tato práce zkoumá existující možnosti a metody detekce korelovaných mutací v proteinech. Práce začíná teoretickým úvodem do zkoumané problematiky. Využití informací o korelovaných mutacích je především při predikci terciální struktury proteinu či hledání oblastí s významnou funkcí. Dále následuje přehled v současnosti používaných metod detekce a jejich výhody a nevýhody. V této práci jsou zkoumány zejména metody založené na statistice (například Pearsonově korelačním koeficientu nebo Pearsonově chi^2 testu), informační teorii (Mutual information - MI) a pravděpodobnosti (ELSC nebo Spidermonkey). Dále jsou popsány nejdůležitější nástroje s informací o tom, které metody používají a jakým způsobem. Také je diskutována možnost návrhu optimálního algoritmu. Jako optimální z hlediska úspěšnosti detekce je doporučeno využít více zmíněných metod. Také je doporučeno při detekci využít fyzikálně-chemických vlastností aminokyselin. V praktické části byla vyvinuta metoda využívající fyzikálně-chemických vlastností aminokyselin a fylogenetických stromů. Výsledky detekce byly porovnány s nástroji CAPS, CRASP a CMAT.
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