The hook that acts as a universal joint connecting these two to transmit motor torque to the propeller.The helical filament that acts as a propeller.The basal body that spans the cell envelope and works as_ a rotary motor.Some inclusion bodies in form of organic (cyanophycean starch and glycogen) and inorganic granules (phosphate and sulphur) are also found.īacterial flagellum : The bacterial flagellum is an organelle for motility made up of three parts:.Cytoplasm of prokaryotes is a pool of all necessary materials like water, enzymes, elements, amino acids, etc.
Some other surface projections are the tubular pili (which help in inter-cellular communication) and fimbriae (for clinging to support). Other parts of flagellum are filament and hook. Both are driven by rotatory movement produced by basal body (which works as motor) of flagellum. In motile bacteria either cilia or flagella are found. The cyanobacteria show more longer extensions called as chromatophores which carry photosynthetic pigments.Cell membrane shows infoldings called mesosomes which help in cell wall formation and DNA replication.It helps in intercellular communication.It is the innermost covering of the cell envelope, chemically composed of lipids and proteins.In Gram-negative bacteria, cell wall is made up of two layers inner layer of Murein or peptidoglycan and outer layer of Lipopolysaccharides.It gives mechanical strength to the cell. The Gram-positive bacteria show presence of peptidoglycan layer in the cell wall and Gram-negative bacteria show presence of murein in the cell wall.It helps in protection of bacterial cell. Other bacteria may have a thick and tough covering called capsule. In some bacteria, glycocalyx occurs in the form of a slime layer (loose sheath).Prokaryotic cell has chemically complex protective cell envelope having glycocalyx, cell wall and plasma membrane.The cell in prokaryotes show following main features : Genetic material is in the form of nucleoid.It does not have membrane bound cell organelles (like endoplasmic reticulum, Golgi complex, mltochondrlai etc.) and well-defined nucleus (nuclear membrane is absent).Prokaryotic cells are primitive type of cells.
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