General characteristics of Bacteria and Mollicutes:
General characteristics of Bacteria and Mollicutes Morphology and Ecology
THE BACTERIAL CELL :
THE BACTERIAL CELL Introduction Shape and size Spheroidal ( cocci ), Cylinderical (bacilli or rods) and Spirillar (spirochetes ).
Arrangement of Bacterial Cells :
Arrangement of Bacterial Cells
Basic Characteristics:
Basic Characteristics Prokaryotic Simplest of all microbial cells Single-celled organisms Distinctive cell walls, or unique cell envelopes, which contain a peptidoglycan layer Tiny; measured in units called micrometers (µm) Lack a true nucleus; instead, have a region called the ‘ nucleoid region' (i.e., DNA) DNA is free floating May have additional DNA which is not associated with this nucleoid region (called a plasmid)
Other Characteristics:
Other Characteristics Rapid growth and cell division (binary fission) under favorable conditions Mutants that arise from bacteria can become extremely resilient organisms because bacteria can: Grow and reproduce cells quickly Adapt quickly to changing environments Plasmids impart additional resistant characteristics to bacteria via cell-to-cell transfer of this extra DNA material Capable of colonizing in almost any environment Extremely diverse and numerous in soils or waters Morphology of bacterial cell The overall form of a basic bacterial cell is that of a complex cell envelope that encloses cell protoplasm. Cell appendages from the envelope protrude into the environment surrounding the cell.
Bacterial cell components:
Bacterial cell components
SURFACE APPENDAGES:
SURFACE APPENDAGES Flagella Monotrichous Lophotrichous Amphitrichous Peritrichious Pilli Sex pilli Common pilli