Cell Wall

The cell wall is the tough, usually flexible but sometimes fairly rigid layer that surrounds some types of cells. It is located outside the cell membrane and provides these cells with structural support and protection, in addition to acting as a filtering mechanism. A major function of the cell wall is to act as a pressure vessel, preventing over-expansion when water enters the cell. Cell walls are found in plants, bacteria, fungi, algae, and some archaea. Animals and protozoa do not have cell walls.

The material in the cell wall varies between species, and can also differ depending on cell type and developmental stage. In bacteria, peptidoglycan forms the cell wall. Archaean cell walls have various compositions, and may be formed of glycoprotein S-layers, pseudopeptidoglycan, or polysaccharides. Fungi possess cell walls made of the glucosamine polymer chitin, and algae typically possess walls made of glycoproteins and polysaccharides. Unusually, diatoms have a cell wall composed of biogenic silica. Often, other accessory molecules are found anchored to the cell wall.

Read more about Cell Wall:  Properties, Plant Cell Walls, Algal Cell Walls, Fungal Cell Walls, Cell Walls of Water and Slime Molds

Other articles related to "cell, cell wall, cell walls, cells, wall":

Subcellular - Anatomy - Prokaryotic Cells
... The prokaryote cell is simpler, and therefore smaller, than a eukaryote cell, lacking a nucleus and most of the other organelles of eukaryotes ... The nuclear material of a prokaryotic cell consists of a single chromosome that is in direct contact with the cytoplasm ... A prokaryotic cell has three architectural regions On the outside, flagella and pili project from the cell's surface ...
Prokaryotic Cell Walls - Archaeal Cell Walls
... Although not truly unique, the cell walls of Archaea are unusual ... is a standard component of all bacterial cell walls, all archaeal cell walls lack peptidoglycan, with the exception of one group of methanogens ... There are four types of cell wall currently known among the Archaea ...
Staining Dyes - In Vivo Vs In Vitro - Specific Techniques - Gram Staining
... It is based on the composition of their cell wall ... staining uses crystal violet to stain cell walls, iodine as a mordant, and a fuchsin or safranin counterstain to mark all bacteria ... Gram status is important in medicine the presence or absence of a cell wall changes the bacterium's susceptibility to some antibiotics ...
Acid Growth
... Acid growth refers to the ability of plant cells and plant cell walls to elongate or expand quickly at low (acidic) pH ... This form of growth does not involve an increase in cell number ... During acid growth, plant cells enlarge rapidly because the cell walls are made more extensible by expansin, a pH-dependent wall-loosening protein ...
L-form Bacteria - Appearance and Cell Division
... Bacterial morphology is determined by the cell wall ... Since the L-form has no cell wall, its morphology is different from that of the strain of bacteria from which it is derived ... Typical L-form cells are spheres or spheroids ...

Famous quotes containing the words wall and/or cell:

    ... the Wall became a magnet for citizens of every generation, class, race, and relationship to the war perhaps because it is the only great public monument that allows the anesthetized holes in the heart to fill with a truly national grief.
    Adrienne Rich (b. 1929)

    What Mrs. Thatcher did for women was to demonstrate that if a woman had enough desire she could do what she wanted, do anything a man could do.... Mrs. Thatcher did not have one traditional feminine cell in her body.
    Julie Burchill (b. 1960)