The cell wall is a rigid andA dense membrane located above the cytoplasmic membrane. This element is characteristic for cells of bacteria, fungi and plants. In addition to protecting the cells, the rigid shell performs a number of other equally important functions.
Cell wall: general information
The cell wall of each organism has a numberfeatures. For example, in bacteria it consists mainly of murein. By the way, bacterial strains are divided into two types - gram-positive and gram-negative - precisely due to the structural features of the rigid shell. This determines their sensitivity to antibiotics.
If we talk about the cell walls of fungi, then theirthe main components are chitin and glucans. But algae shells can consist of different polysaccharides - mainly glucose and its compounds. By the way, the composition of the cell membrane of algae is a very important taxon. It is worth remembering about the Diatom Algae group, whose representatives synthesize their own wall from silica.
Cellular wall of plants and its functions
Principles of the structure of a rigid cell membraneit is most convenient to study using the example of a plant cell. And although mechanical protection is one of the most important functions of the cell wall, it has a much greater significance:
Structure of the cell wall
In the plant wall, it is common to distinguish three main components: a framework, a matrix and inlaying substances.
The cell wall of the plant consists of cellulose. Due to the formation of hydrogen bonds, the cellulose molecules form strong microfibrils that are immersed in the base material, or matrix.
The cell wall matrix is approximately60% of its total mass. It fills the space between the microfibrils, and also creates strong bonds between the macromolecules, ensures the elasticity and strength of this cellular structure. The main components of the matrix are hemicellulose and pectin.
The encrusting substances are in most cases lignin, which is about 30% of the dry mass of the cell wall.
Quite often, substances such as kutin, suberin and wax are deposited on the outer surface of the cell membrane.
Suberin is deposited on the insidecell membrane, providing a process of culling. Such a cell becomes absolutely impermeable to moisture, therefore its content quickly dies off, and the free space is filled with air.
The main function of wax substances and cuticles is to protect cells from infection, as well as to reduce the level of evaporation of water.
We can say that the cell wall is a very important element of the plant cell, which ensures its normal development.