Photosynthetic organisms eukaryotic

Eukaryotes (multicellular) Plants Fungi Animals Sedentary photosynthetic organisms Filamentous, sedentary Mobile foraging organisms with senses and later a nervous system, use of Na, K, Cl... 

Fig. 2. An evolution diagram illustrating a suggestion of common ancestry of some present-day organisms. The essential features of present-day photosynthesis may have originated in the prebiotic era and is preserved in its most primitive form in (at least some) present-day phototrophs. The heterotrophs may have developed parallel with the aerobic nonphotosynthetic bacteria, some l to 1.5 x 109 years after the emergence of the cyanobacteria. The eukaryotic photosynthetic organisms developed much later, perhaps some 1.5 to 0.5 x 109 years ago. The archaebacteria are primitive organisms that seem to have no evolutionary relation with the present prokaryotes.21 Little is known about their energy metabolism. Tentatively, they are considered as a very early form of cellular life.

Fig. 3 Schematic model of light-harvesting compartments in photosynthetic organisms and their position with respect to the membrane and the reaction centers. RC1(2) Photosystem I(II) reaction centre. Peripheral membrane antennas Chlorosome/FMO in green sulfur and nonsulfur bacteria, phycobilisome (PBS) in cyanobacteria and rhodophytes and peridinin-chlorophyll proteins (PCP) in dyno-phytes. Integral membrane accessory antennas LH2 in purple bacteria, LHC family in all eukaryotes. Integral membrane core antennas B808-867 complex in green nonsulfur bacteria, LH1 in purple bacteria, CP43/CP47 (not shown) in cyanobacteria and all eukaryotes.

Eukaryotic photosynthetic organisms include various types of algae, mosses, ferns and higher plants. In all these organisms, photosynthesis is confined to a subceUular organelle known as the Chloroplast. In many ways, the chloroplast is similar to certain types of photosynthetic bacteria, and can... 

Eukaryotic, non-photosynthetic organisms that obtain their nutrients by the absorption of compounds from their surroundings. 

These observations suggest a lateral transfer of cellulose synthase from cyanobacteria to D. discoideum. However, while the primary and secondary endo-symbiotic events that led to the evolution of plastids in plants and algae provide a clear mechanism for the transfer of a cyanobacterial cellulose synthase to photosynthetic organisms, such a mechanism is lacking for D. discoideum. Cyanobacterial genes are known to exist in eukaryotes which have secondarily lost plastids. However, there is no evidence for the existence of an endosymbiotic relationship between ancestors of D. discoideum and a cyanobacterium. Therefore, if a lateral transfer occurred, it was likely xenologous, possibly via a food ratchet mechanism (Doolittle 1998). 

Coupling factor one (CFl) complexes have been isolated and characterized from a wide variety of photosynthetic organisms These include bacteria (Beechy et al., 1975) thermophilic cyanobacteria (Binder, Bachofen, 1979), unicellular, eukaryotic green algae (Selman-Reimer et al., 1981), and higher (vascular) plants (Nelson, 1976). 

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