REGNUM PROKARYOTAE
Prokaryotes: unicellular microorganisms of 0.1-15 um, presenting
rod or coccus shape, sometimes filamentous or mycelial forms
may occur. They are widely distributed in nature (soil, water,
foods, plants, animals, rarely hot springs or radioactive medium).
Cells have a single circular DNA chromosome, contained within a
region called the nucleoid & may also have various small circular
pieces of DNA (plasmids) inside the cell. The nucleoplasm is not
separated from the cytoplasm by a nuclear membrane.
Reproduction is most often asexual, through binary fission,
occasionally by budding. Cells may remain attached after division
resulting specific arrangements (strepto-, staphylo- etc.).
The cells are surrounded by a rigid peptidoglicans based wall with
the exception of the Mollicutes. The plasma membrane forms
vesicular, lamellar or tubular intrusions into the cytoplasm.
Respiratory and photosyntetic functions are associated with the
plasma membrane system (where available).
Ribosomes of the 70S type are dispersed in the cytoplasm.
Kingdom Prokaryotae includes Cyanobacteria (blue-green algae)
and Bacteria. The last makes the object of our pages.

Bacteria identification software. Free access
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Antibiotic database & antibiogram analyser
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Salmonella isolation & identification scheme
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Copyright [CS] (c) 2006 All rights reserved
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Note de curs Medicina Veterinara
Cursuri, schite, desene, tabele & lucrari.
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