BIO153H5 Lecture Notes - Lecture 7: Chromalveolata, Rhizaria, Nuclear Membrane
Document Summary
Capacity to photosynthesis (a lot of lost) Protists behaved like animals as chase other organisms. Protists behaved like plants as could photosynthesise. According to history of earth, earliest life forms were in aquatic environments. This was because of low o2 concentration in atmosphere and there was o2 in the water no ozone layer. No zone layer means no protection from the radiation of sun, so underwater allowed an advantage. Protists don"t have a true multicellularity . Form colonies, but cells are not connected by cytoplasm. Collection of same cells but not divergent cells. Cells are of same type, any new cell can form a colony. Protista includes both nucleated and non-nucleated cells. The resistriction in the past as some protists were eukaryotes and some were prokaryote but were grouped together. It was concluded that prokaryotes and eukaryotes diverged very early in history so not closely related.
