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Euglenids (Excavata: Euglenophyta): Important Species
Bryxová, Tereza ; Říhová, Dagmar (advisor) ; Hanel, Lubomír (referee)
This bachelor thesis focuses on a detailed description of euglenids (Excavata: Euglenozoa), and selected important species from the class Euglenophyta. Euglenids are unicellular mostly free-living flagellates. Their most closely related protozoans are those from the group called Kinetoplastida. Members of Euglenophyta have specific and unique cell structure. A specific organelle, the stigma (also called eye spot), formed by a large number of pigment granules, helps them to perceive the direction from which light comes. An important part of the cell are also plastids, which cause different colouration of euglenids, and thus also colour of freshwater bodies in which they occur. Mobile stages of euglenids possess two flagella (sometimes only one flagellum is present - e.g. genus Euglena) which are anchored in small cavity called ampula. The surface of the flagellum is covered with fine hairs, mastigonemes. The thesis closely focuses on three euglenid species. Euglena viridis is characterized by its green colour and forms characteristic green clusters visible on the water surface of water bodies. Euglena gracilis is of great importance as a potential source in biotechnological use. It is one of the future sources of biofuels or healthy bioproducts. The last closely described model representative is...
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Norway spruce chloroplast ultrastructure - heterogeneity within a needle.
Glanc, Natália ; Lhotáková, Zuzana (advisor) ; Kutík, Jaromír (referee)
6 Abstract Temperate forests serve as long term carbon storage and are affected by increasing carbon dioxide (CO2) concentration in the atmosphere. Norway spruce (Picea abies (L.) Karst.) is the most abundant conifer in the forests of the Czech Republic, therefore I studied the response of its photosynthetic aparatus to elevated CO2 concentration. The aim of my thesis was to analyze the impact of CO2 concentration on chloroplast ultrastructure in both shaded and exposed needles, focusing on the volume density of starch in the median cross-sections of mesophyll cell chloroplasts. The next aim of the study was to test whether the chloroplasts of the first subepidermal layer of mesophyll are representative for the whole needle with respect to starch volume density. The study was performed on eleven years-old Norway spruce trees that had been exposed to ambient or elevated concentration of CO2 for six years; the experiment had been carried out at the Bílý Kříž experimental station in the Beskids Mountains in cultivation chambers with automatically adjustable windows. First year needles of trees grown under abient (382-395ppm) or elevated (700 ppm) CO2 concentration were collected in October 2011. The needles were used to prepare ultrathin sections and the images of median chloroplast cross-sections were...
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Structure and function of chloroplasts in selected woody plants grown under increased CO2 concentration
Hlízová, Eliška ; Albrechtová, Jana (advisor) ; Kutík, Jaromír (referee)
The effect of elevated CO2 concentration (EC CO2) on photosynthesis has been observed on many hierarchical levels. There was a significant increase in the rate of photosynthesis of examined trees observed in previous studies thus I hypothesised these changes are accompanied by changes of chloroplast ultrastructure and photosystem content and function and the main aim of this study is to evaluate these adjustments. In this study 13 - 14 years old seedlings of Norway spruce (Picea abies L. Karst.) grown in glass domes with adjustable windows - one with ambient CO2 concentration as a control, the other one with simulated EC CO2 (700 ppm) - during the vegetative season were examined. Pigment content, fluorescence and reflectance indexes, activity of photosystem 1 (PS1) and 2 (PS 2) of isolated chloroplasts, size of cross-sectional area of chloroplast and proportion of stromal to granal thylakoids under EC CO2 treatment were investigated. Although there was a significant increase in the maximum rate of photosynthetic assimilation of trees from EC CO2 (observed by other researchers of our team), decreased chlorophyll and carotenoid content as well as the activity of both photosystems were observed, which is usually atributed to photosynthetic acclimation. As the rate of decrease of photosystem 1 and photosystem 2...
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Study of quantitative parameters of Norway spruce needle structure under the effect of elevated CO₂ concentration and different irradiance
Kubínová, Zuzana ; Lhotáková, Zuzana (advisor) ; Urban, Otmar (referee) ; Gebauer, Roman (referee)
Zuzana Kubínová: Study of Quantitative Parameters of Norway Spruce Needle Structure under the Effect of Elevated CO2 Concentration and Different Irradiance, Doctoral Thesis, Prague 2019 Abstract Atmospheric concentration of CO2 is increasing, while its influence on plants is still not fully elucidated. Norway spruce (Picea abies L. Karst.) is an abundant conifer tree in European temperate and boreal forests, which behave as carbon sink in the global carbon cycle. The physiological response to elevated CO2 concentration may be interconnected with changes in leaf anatomy and morphology. Needle structure is also determined by other factors in addition to CO2 concentration, irradiance being the most important one. Thus, effect of irradiance was also included in our studies. The effects of elevated CO2 concentration and irradiance on Norway spruce needle structure were studied using new applications of well-established quantitative methods and novel methods enabling effective and unbiased analysis of needle structural traits. The General Procrustes analysis showed to be effective for needle shape on cross section comparison and the disector method proved to be suitable for chloroplast number estimates. The influence of elevated CO2 concentration and different irradiance on needle structure was studied at two...
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Study of quantitative parameters of Norway spruce needle structure under the effect of elevated CO₂ concentration and different irradiance
Kubínová, Zuzana ; Lhotáková, Zuzana (advisor) ; Urban, Otmar (referee) ; Gebauer, Roman (referee)
Zuzana Kubínová: Study of Quantitative Parameters of Norway Spruce Needle Structure under the Effect of Elevated CO2 Concentration and Different Irradiance, Doctoral Thesis, Prague 2019 Abstract Atmospheric concentration of CO2 is increasing, while its influence on plants is still not fully elucidated. Norway spruce (Picea abies L. Karst.) is an abundant conifer tree in European temperate and boreal forests, which behave as carbon sink in the global carbon cycle. The physiological response to elevated CO2 concentration may be interconnected with changes in leaf anatomy and morphology. Needle structure is also determined by other factors in addition to CO2 concentration, irradiance being the most important one. Thus, effect of irradiance was also included in our studies. The effects of elevated CO2 concentration and irradiance on Norway spruce needle structure were studied using new applications of well-established quantitative methods and novel methods enabling effective and unbiased analysis of needle structural traits. The General Procrustes analysis showed to be effective for needle shape on cross section comparison and the disector method proved to be suitable for chloroplast number estimates. The influence of elevated CO2 concentration and different irradiance on needle structure was studied at two...
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Grana
Hlavsová, Kateřina ; Duchoslav, Miloš (advisor) ; Kutík, Jaromír (referee)
The evolution of life on Earth is closely connected to the ability of some organisms to oxidise water and reduce carbon dioxide using solar energy in a process called oxygenic photosynthesis. Substantial part of the photosynthetic reactions is located in the thylakoid membrane inside of chloroplasts and cyanobacteria. The main photosynthetic complexes in the thylakoid membrane are photosystems I and II with their light harvesting antennas, cytochrome complex and ATP synthase. All higher plants form grana (stacks of appressed thylakoid membranes) that are interconnected by stroma lamellae. Proper distribution of certain processes between grana and stroma lamellae seems to be crucial for smooth flow of photosynthesis. First part of this thesis is focused on the major photosynthetic complexes while the second part focuses on grana structure, dynamics and stabilising forces as well as proteins essential for grana formation. The last part of the thesis describes some differences between granal and agranal organisms and summarises hypotheses about grana functions.
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Norway spruce chloroplast ultrastructure - heterogeneity within a needle.
Glanc, Natália ; Lhotáková, Zuzana (advisor) ; Kutík, Jaromír (referee)
6 Abstract Temperate forests serve as long term carbon storage and are affected by increasing carbon dioxide (CO2) concentration in the atmosphere. Norway spruce (Picea abies (L.) Karst.) is the most abundant conifer in the forests of the Czech Republic, therefore I studied the response of its photosynthetic aparatus to elevated CO2 concentration. The aim of my thesis was to analyze the impact of CO2 concentration on chloroplast ultrastructure in both shaded and exposed needles, focusing on the volume density of starch in the median cross-sections of mesophyll cell chloroplasts. The next aim of the study was to test whether the chloroplasts of the first subepidermal layer of mesophyll are representative for the whole needle with respect to starch volume density. The study was performed on eleven years-old Norway spruce trees that had been exposed to ambient or elevated concentration of CO2 for six years; the experiment had been carried out at the Bílý Kříž experimental station in the Beskids Mountains in cultivation chambers with automatically adjustable windows. First year needles of trees grown under abient (382-395ppm) or elevated (700 ppm) CO2 concentration were collected in October 2011. The needles were used to prepare ultrathin sections and the images of median chloroplast cross-sections were...
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Regulation of cytokinin metabolism in tobacco plants and chloroplasts
Havlová, Marie ; Vaňková, Radomíra (advisor) ; Ryšlavá, Helena (referee) ; Malá, Jana (referee)
Cytokinins (CKs) are one of the most important group of phytohormones influencing many processes throughout the whole plant. As many processes are regulated both by the light and phytohormones, the first part of this work has been focused on evaluation of diurnal rhytmicity in levels of cytokinins and other cooperating hormones like auxin (indol-3-acetic acid, IAA), abscisic acid (ABA) and polyamines (PA). The changes in activity of selected enzymes participating in metabolism of the above mentioned phytohormones were followed as well. Diurnal variation of phytohormones was tested in tobacco leaves (Nicotiana tabacum L. cv. Wisconsin 38) grown under a 16/8 h (light/dark) period. The main peak of the physiologically active forms of CKs, found after the middle of the light period, coincided well with the maximum of IAA and PA levels and with activity of the corresponding enzymes. The achieved data indicate that metabolism of CKs, IAA and PAs is tightly regulated by the circadian clock. The other part of the study has been focused on changes in the contents of CKs, IAA and ABA in transgenic tobacco plants with altered cytokinin metabolism, achieved via the over-expression of particular enzymes participating in CK metabolism (biosynthesis, degradation and reversible conjugation). As CKs are known to be...
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Structure and function of chloroplasts in selected woody plants grown under increased CO2 concentration
Hlízová, Eliška ; Albrechtová, Jana (advisor) ; Kutík, Jaromír (referee)
The effect of elevated CO2 concentration (EC CO2) on photosynthesis has been observed on many hierarchical levels. There was a significant increase in the rate of photosynthesis of examined trees observed in previous studies thus I hypothesised these changes are accompanied by changes of chloroplast ultrastructure and photosystem content and function and the main aim of this study is to evaluate these adjustments. In this study 13 - 14 years old seedlings of Norway spruce (Picea abies L. Karst.) grown in glass domes with adjustable windows - one with ambient CO2 concentration as a control, the other one with simulated EC CO2 (700 ppm) - during the vegetative season were examined. Pigment content, fluorescence and reflectance indexes, activity of photosystem 1 (PS1) and 2 (PS 2) of isolated chloroplasts, size of cross-sectional area of chloroplast and proportion of stromal to granal thylakoids under EC CO2 treatment were investigated. Although there was a significant increase in the maximum rate of photosynthetic assimilation of trees from EC CO2 (observed by other researchers of our team), decreased chlorophyll and carotenoid content as well as the activity of both photosystems were observed, which is usually atributed to photosynthetic acclimation. As the rate of decrease of photosystem 1 and photosystem 2...
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