Sökning: "Organic-walled microfossils"

Hittade 2 uppsatser innehållade orden Organic-walled microfossils.

1. 1. Biodiversity of Organic-Walled Eukaryotic Microfossils from the Tonian Visingsö Group, Sweden

   Master-uppsats, Uppsala universitet/Institutionen för geovetenskaper

   Författare :Corentin Loron; [2016]
   Nyckelord :Organic-walled microfossils; Tonian; cyst; green algae; eukaryote; Visingsö Group; Mikrofossil med organiska cellväggar; tonian; cysta; grönalger; eukaryot; Visingsö gruppen;

   Sammanfattning : The diversification of unicellular, auto- and heterotrophic protists and the appearance of multicellular microorganisms is recorded in numerous Tonian age successions worldwide, including the Visingsö Group in southern Sweden. The Tonian Period (1000-720 Ma) was a time of changes in the marine environments with increasing oxygenation and a high input of mineral nutrients from the weathering continental margins to shallow shelves, where marine life thrived. LÄS MER

3. 2. The life cycle and developmental phases of Cambrian-Ordovician organic-walled microfossils from Kolguev Island, Arctic Russia.

   Master-uppsats, Uppsala universitet/Institutionen för geovetenskaper

   Författare :Magdalena Pazio; [2016]
   Nyckelord :Saharidia fragilis; Prasinophyceae algae; life cycle; acritarchs; Saharidia fragilis; Prasinophyceae; livscykel; acritarch;

   Sammanfattning : Light microscopy studies of collections of late Cambrian/Early Ordovician organic-walled microfossils, informally called acritarchs, provide the observations on phenotypic traits that are comparable to Modern microalgae and make possible recognition of various developmental stages in their complex life cycle. The exceptionally preserved Saharidia fragilis microfossils show the internal body within the vesicle and the formation of the fringe and pylome, the opening for releasing of the daughter cells from the phycoma-like cyst. LÄS MER