Search for dissertations about: "ancestral"

Showing result 16 - 20 of 144 swedish dissertations containing the word ancestral.

  2. 16. Reconciling gene family evolution and species evolution

    Author : Joel Sjöstrand; Jens Lagergren; Nicolas Lartillot; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Computational biology; Bioinformatics; Phylogenetics; Phylogenomics; Comparative genomics; Evolutionary biology; datalogi; Computer Science;

    Abstract : Species evolution can often be adequately described with a phylogenetic tree. Interestingly, this is the case also for the evolution of homologous genes; a gene in an ancestral species may – through gene duplication, gene loss, lateral gene transfer (LGT), and speciation events – give rise to a gene family distributed across contemporaneous species. READ MORE

  4. 17. Evolution of the Neuropeptide Y and Opioid Systems and their Genomic Regions

    Author : Görel Sundström; Dan Larhammar; Manfred Schartl; Uppsala universitet; []
    Keywords : neuropeptide Y; opioid; evolution; genome duplication; gene duplication; Hox; SCN; IGFBP; MEDICINE; MEDICIN;

    Abstract : Two whole genome duplications (2R) occurred early in vertebrate evolution. By using combined information from phylogenetic analyses and chromosomal location of genes, this thesis delineates the evolutionary history of two receptor-ligand systems that expanded by these large scale events. READ MORE

  5. 18. Hyperoxia avoidance and aggregation behavior in C. elegans

    Author : Annelie Persson; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; c. elegans; aggregation;

    Abstract : Living in the soil, C. elegans can move in three dimensions in search for food. To navigate, it partly uses oxygen levels as a description of its habitat. Oxygen tension may indicate presence of microbial food and location with respect to the surface, where oxygen is 21%. READ MORE

  6. 19. On the evolutionary origin of the vertebrate cortex

    Author : Shreyas M Suryanarayana; Karolinska Institutet; Karolinska Institutet; []
    Keywords : ;

    Abstract : The aim of this thesis is to dissect out the minimalistic ancestral neural hardware, which has been conserved in homologue structures of the cerebral cortex and in particular the neocortex, across vertebrates. For this purpose, we utilise the lamprey - a cyclostome (jawless vertebrate), and we compare its anatomical homologue of cortex, the lateral pallium (LPal), in terms of its connectivity, cytoarchitecture and sensory organisation with that of the mammalian neocortex. READ MORE

  7. 20. Culture-independent methods and high-throughput sequencing applied to evolutionary microbial genomics

    Author : Anders E. Lind; Thijs JG Ettema; Purificación López-García; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Single cell genomics; metagenomics; amplicon; archaea; haloarchaea; endosymbiosis; ciliate; hydrogenosome; tree reconciliation;

    Abstract : Culture-independent methods allow us to better understand the diversity of microorganisms on earth. By omitting the culturing step, we can gain access to species previously out of our reach.To better capture and understand the diversity of microorganisms, we have developed an alternative to 16S amplicon sequencing. READ MORE