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Think of the cell wall as a wicker basket in which a balloon has been inflated so that it exerts pressure from the inside. Such a basket is very rigid and resistant to mechanical damage. Thus does the prokaryote cell (and eukaryotic cell that possesses a cell wall) gain strength from a flexible plasma membrane pressing against a rigid cell wall ...
These bacteria are characterised by a rigid cell wall. They may either be motile or nonmotile. If motile, they have a flagellum. A typical flagellum consists of a basal body, filament, and hook. The long filament is the organ which helps eubacteria move. [citation needed] [citation needed]
The function or significance of mitosis, is the maintenance of the chromosomal set; each formed cell receives chromosomes that are alike in composition and equal in number to the chromosomes of the parent cell. Mitosis occurs in the following circumstances: Development and growth: The number of cells within an organism increases by mitosis.
The cells of the filaments are arranged end to end. They are cylindrical or barrel-shaped. [2] The apical cell is somewhat rounded at its terminal end whereas the basal cell is elongated. It is also called the basal holdfast, which attaches the filament to the substratum. The cell wall is composed of propectin and cellulose and it lacks mucilage.
Since the cell wall is required for bacterial survival, but is absent in some eukaryotes, several antibiotics (notably the penicillins and cephalosporins) stop bacterial infections by interfering with cell wall synthesis, while having no effects on human cells which have no cell wall, only a cell membrane
Cytokinesis illustration Ciliate undergoing cytokinesis, with the cleavage furrow being clearly visible.. Cytokinesis (/ ˌ s aɪ t oʊ k ɪ ˈ n iː s ɪ s /) is the part of the cell division process and part of mitosis during which the cytoplasm of a single eukaryotic cell divides into two daughter cells.
Sarcina cells, for example, are arranged in cubical pockets because cell division alternates regularly among the three perpendicular planes. Streptococcus spp. resemble a string of beads because division always occurs in the same plane. Some of these strings, for example, S. pneumoniae, are only two cells long.
The elementary body may be 0.25 to 0.30 μm in diameter. This form is covered by a rigid cell wall (hence the combining form chlamyd-in the genus name). The elementary body induces its own endocytosis upon exposure to target cells. One phagolysosome usually produces an estimated 100–1000 elementary bodies.