Search for dissertations about: "biological cycle"

Showing result 1 - 5 of 530 swedish dissertations containing the words biological cycle.

  1. 1. Reproductive physiology of the female three-spined stickleback, Gasterosteus aculeatus

    Author : Chrysoula Roufidou; Bertil Borg; Geir Lasse Taranger; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; overripening of eggs; spawning cycle; brain-pituitary-gonad BPG axis; vitellogenin; ovarian fluid; sex steroids; reproduction; three-spined stickleback; Gasterosteus aculeatus; fish; funktionell zoomorfologi; Functional Zoomorphology;

    Abstract : Reproduction in vertebrates, including fishes, is under control of the brain-pituitary-gonad (BPG) axis. The female three-spined stickleback, Gasterosteus aculeatus, produces egg clutches at intervals of a few days and spawns them in a nest built by male. READ MORE

  2. 2. Genomic and morphological diversity of marine planktonic diatom-diazotroph associations : a continuum of integration and diversification through geological time

    Author : Andrea Caputo; Rachel Ann Foster; Monika Quinones Winder; Ramon Massana; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; phytoplankton; diatoms; cyanobacteria; diazotrophs; symbiosis; evolution; phylogenetics; confocal microscopy; qPCR; CARD-FISH; tropics; sub-tropics; Marine Ecology; marin ekologi;

    Abstract : Symbioses between eukaryotes and nitrogen (N2)-fixing cyanobacteria (or diazotrophs) are quite common in the plankton community. A few genera of diatoms (Bacillariophyceae) such as Rhizosolenia, Hemiaulus and Chaetoceros are well known to form symbioses with the heterocystous diazotrophic cyanobacteria Richelia intracellularis and Calothrix rhizosoleniae. READ MORE

  3. 3. Intramolecular isotope analysis reveals plant ecophysiological signals covering multiple timescales

    Author : Thomas Wieloch; Jürgen Schleucher; Mats Nilsson; Gerd Gleixner; Lisa Wingate; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NMR spectroscopy; tree ring; isotope ratio; isotope effect; intramolecular 13C 12C signal; carbon allocation; acclimation; plant performance; climate reconstruction; plant ecophysiology;

    Abstract : Our societies' wellbeing relies on stable and healthy environments. However, our current lifestyles, growth-oriented economic policies and the population explosion are leading to potentially catastrophic degradation of ecosystems and progressive disruption of food chains. READ MORE

  4. 4. Violaxanthin De-epoxidase and the Xanthophyll Cycle

    Author : Anna Gisselsson; Biokemi och Strukturbiologi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Plant biochemistry; zeaxanthin.; xanthophyll cycle; violaxanthin de-epoxidse; thylakoid; regulation; quenching; protonation; pH-dependence; light stress; histidine; Conformational change; domains; Växtbiokemi;

    Abstract : The xanthophyll cycle is a mechanism for short term adaptation of plants to varying light intensities. It involves a reversible conversion of violaxanthin to zeaxanthin, via the intermediate antheraxanthin, upon high light intensities. READ MORE

  5. 5. How could Christmas trees remain evergreen? : photosynthetic acclimation of Scots pine and Norway spruce needles during winter

    Author : Pushan Bag; Stefan Jansson; Fransis Andre Wollman; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Scots Pine; Norway spruce; Photosynthesis; Winter adaptation; biologisk kemi; biological chemistry; biology; biologi; molekylärbiologi; Molecular Biology; Physiological Botany; fysiologisk botanik;

    Abstract : Plants and other green organisms harvest sunlight by green chlorophyll pigments and covertit to chemical energy (sugars) and oxygen in a process called photosynthesis providing the foundation for life on Earth. Although it is unanimously believed that oceanic phytoplanktons are the main contributors to the global photosynthesis, the contribution of coniferous boreal forests distributed across vast regions of the northern hemisphere cannot be undermined. READ MORE