A plant cell is an elementary unit of a living organism - a plant. It contains components that are inherent in all eukaryotic organisms: nucleus, cytoplasm, Golgi apparatus, mitochondria, endoplasmic reticulum, ribosomes and lysosomes, microtubules. However, the plant cell has differences - it is the presence of plastids, vacuoles and cellulose walls.
Unites all organelles with each other and takes part in the metabolism of a special semi-fluid medium of the living unit (cell) - the cytoplasm. The structure of the cytoplasm is quite complex. It is a multicomponent colloidal solution that can pass from the sol to the gel. At the same time, the entire cell is permeated with protein filaments, which form the cytoskeleton of the structural unit. Its composition includes water, which accounts for 60 to 90% of the total mass, proteins (10-20%) and lipids (up to 23%), as well as organic and inorganic substances. The role of cytoplasm in cell life is very high:
- It is the medium in which chemical reactions occur;
- Actively participates in metabolism;
- Supports turgor and thermoregulation;
- Performs a supporting function, helps the cell to keep its shape.
The effect on the semi-fluid medium is exerted by cells And external factors - temperature, light, air composition, amount of water. All this directly affects the movement of the cytoplasm, in which she constantly resides. Due to the movement of the colloidal solution with nutrients (oxygen, ATP, etc.), the unit unit of a living organism exists. The vital activity of a cell is accomplished by a combination of physiological processes. The nutrition of the structural unit of a living organism occurs in the course of biochemical reactions, as a result of which inorganic substances are transformed into organic substances . Breathes the plant cell with oxygen, formed during the oxidation of complex substances - carbohydrates, lipids, amino acids. Simultaneously, during breathing, the synthesis and release of energy necessary to sustain life occurs. The plant cell grows by stretching Cellulose wall and increase the volume of the cytoplasm and vacuoles.
Together, all these vital processes take part in the metabolism, the main essence of which is the formation of new products, their decomposition into smaller components, the removal of decay products from the cell or deposition in the form of reserve substances. The allocation of unnecessary links occurs through the cell wall, and the movement, collection (formation) of new structures is due to the movement of the cytoplasm.
An important property of cells is their ability to multiply by division. The result of this process is the formation of two daughter structural units of a living organism that have a set of chromosomes identical to the parent one.
Thus, the plant cell is the smallest living structure of the body, it feeds, breathes, reacts to stimuli, grows and multiplies, and the cytoplasm and the organelles immersed in it participate in the metabolism.