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The effects of irradiation on plant photomorphogenesis in highschool biological education
Sedlecký, Libor ; Albrechtová, Jana (advisor) ; Pavlová, Libuše (referee)
Light does not serve plants only as a source of energy, but it mediates the information about the environmental conditions and brings signal information for developmental processes taking place in plants. Radiation within the whole spectrum range can be produced by a natural source, or an artificial source. Radiation is percived by a plant due to the whole range of receptors, known as photoreceptors - receptor molecules. Because of photoreceptors plant is able to adapt to its enviromnent and to adjust its metabolism to be as effective as possible. In photomorphogenetic reactions a plant responds mostly to red, blue and partly ultraviolet part of electromagnetic spectrum. For the red radiation there is only one receptor - phytochrome, existing in two various conformations and in several species. Phytochrome is one of the most studied photoreceptors. Blue visible light and partly also ultraviolet radiation is therefore percieved through cryptochromes, which were resistant to research for a long time. In photomorfogenesis there is an enormous difference in plant reactions to light and dark condition. Very different response is observed in various radiation conditions and different physiological events are triggerred and take place. One of the main reactions occurring during change from dark to light...
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Fotomorfogeneze: the effects of irradiation on plant development in the eductational programs of basic schools and highschools
Sedlecký, Libor ; Albrechtová, Jana (advisor) ; Janštová, Vanda (referee)
The main aim of this diploma thesis was creation of functional experiments and supporting teaching materials for high school students which would clearly demonstrate the processes of photomorphogenesis in plants. Proposed experiments had to be verified in practice on the basis of their reliability, repeatability and reproducibility in schools. It was necessary to drew up the educational materials for each experiment focused on observation of photomorphogenesis plant's reactions. These materials give students the basics of scientific work and specifically they increase the interest in experimental plant biology. The first part of the thesis is literary introduction that provides the theoretical background to the topic of photomorphogenesis for teachers. It summarizes the current of the art mechanisms and manifestations of photomorphogenesis processes of plants. The second didactic part of the introduction deals with the framing up teaching of plant physiology into current curricula of education in the Czech Republic. For the formativ of educational materials experiments had to be designed to demonstrate reliably basic photomorphogenetical processes. Three experiments were designe dat: 1. plant phototropism, 2. negative plant phototropism and 3. plant scotomorphogenesis.To select these experiments I...
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The effects of irradiation on plant photomorphogenesis in highschool biological education
Sedlecký, Libor ; Albrechtová, Jana (advisor) ; Pavlová, Libuše (referee)
Light does not serve plants only as a source of energy, but it mediates the information about the environmental conditions and brings signal information for developmental processes taking place in plants. Radiation within the whole spectrum range can be produced by a natural source, or an artificial source. Radiation is percived by a plant due to the whole range of receptors, known as photoreceptors - receptor molecules. Because of photoreceptors plant is able to adapt to its enviromnent and to adjust its metabolism to be as effective as possible. In photomorphogenetic reactions a plant responds mostly to red, blue and partly ultraviolet part of electromagnetic spectrum. For the red radiation there is only one receptor - phytochrome, existing in two various conformations and in several species. Phytochrome is one of the most studied photoreceptors. Blue visible light and partly also ultraviolet radiation is therefore percieved through cryptochromes, which were resistant to research for a long time. In photomorfogenesis there is an enormous difference in plant reactions to light and dark condition. Very different response is observed in various radiation conditions and different physiological events are triggerred and take place. One of the main reactions occurring during change from dark to light...
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Circadian rhythm of secondary alga Chromera velia
JONÁKOVÁ, Martina
A life cycle of many known algae is influenced by the circadian clock. It seems probable that also Chromera velia, the closest known photosynthetic relative to Apicomplexa, uses circadian oscillator. We tested, if fluctuating of zoospore?s abundance is driven by the circadian clock. This rhythm is stable even in the constant light condition. Furthermore, three cryptochrome genes, involved in circadian rhythms, were sequenced and consequently phylogenetically investigated. Two of them were classified as CRY-DASH, the third is CRY-DASH-like. The rhythmicity of CRY-DASH expression in C. velia was also investigated. The level of expression was also tested under constant light and dark condition. It was suggested that expression of these genes is associated with the circadian oscillator. This is the first study of the circadian clock in C. velia.
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Function of retina of Homing pigeon \kur{Columba livia} in magnetoreception
BAJGAR, Adam
Many animals have ability to percieve the magnetic field of the Earth and use this clue for both orientation and navigation. Yet little is known about physiological mechanism that underlies this sensory ability. Although physiological mechanism still remains unclear, there are three major hypotheses how animals can detect the magnetic field. In this study I focused on the radical pair theory. I analyzed how manipulation of the ambient magnetic field influence the expression of CRY 1, CRY 2 and c-Fos in the pigeon´s retina. I observed in incerased numbers of CRY1, c-Fos and CRY1+c-Fos possitive cells in the ihned nuclear layer (INL) of the retina in animals sbjected to the periodical manipulation of the magnetic field inclination. These data demonstrate that the INL constains a population of neurons that are responsive to magnetic stimuli and strongly suggest that Cry 1 is involved in detection of the Earth magnetic field.
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