Meaning of Plant Cell
When analyzing eukaryotic cells, it is possible to find several similarities between plant and animal cells. This is due to the fact that there are structures that the groups share, that is, they are present in both one and the other, as is the case with ribosomes, the plasma membrane, and mitochondria, among other elements.
Another aspect that gives similarity between the groups is the existence of structures that, although they are different, basically play the same role.
Like all eukaryotes, plant cells have a plasma membrane, genetic material delimited by a nuclear envelope called a library and, immersed in the cytoplasm, several membranous and non-membranous organelles that carry out the vital and functional functions of the cell. However, they have differences compared to other eukaryotic, animal cells.
Vegetables, however complex they may be, are beings that are not looking for food.
Therefore, another strategy is needed to obtain nutrients and energy. Some of these nutrients and water are obtained from the root because they are present in the substrate on which the vegetable stands. However, the energy comes from glucose and it is not free or present in the soil.
In this sense, the strategy used by these organisms is based on a process called photosynthesis.
Photosynthesis is, in short, a chemical reaction that occurs in cells by sunlight, carbon dioxide, and water, resulting in the production of glucose and the release of oxygen.
This process is characteristic of beings called autotrophs, that is, they “produce” their own food.
One of the differences between animal and plant cells is precisely a plastid responsible for the process mentioned in the previous paragraph.
This organelle is called a chloroplast. Plastids are large membranous organelles composed of two membranes, one internal and one external. These structures may have non-photosynthetic pigments, the chromoplast, or non-pigmented leukoplast.
In the case of plant cell photosynthesis, the plastid in question is the chloroplast, a plastid pigmented green by a substance called chlorophyll.
The cell wall is a structure absent in animal cells and present in plant cells. They are a semi-rigid shell external to the plasmatic membrane, basically composed of cellulose.
This envelope, also known as cellulosic membrane, has as its main functions the protection and stability of the cell shape.
This is because the rigidity of this structure protects the cell against impacts and injuries (mechanical protection) and, the external association with the membrane, makes the wall a protective barrier against infections and attacks from other organisms (physical protection). ).
This same characteristic, stiffness, is what triggers the stability of cell shape and size.
This is due to the fact that this envelope provides the cell with the capacity to resist the pressures of the internal and external media that would alter its characteristics.
In general, there are certain levels of communication between cells, that is, there is the transfer or movement of substances from one cell to another. While in animal cells this communication takes place through gap junctions, in plant cells this takes place through plasmodesmata.
These structures are peripheral regions in which there is no cellulose deposit -cell wall-, which ends up forming small tubes that connect one cell with the adjacent one. Therefore, it is the plasmodesmata that make it possible for molecules to be exchanged from one cell to another.
In another aspect, there are two other characteristics that are very clear in the difference of the groups.
Cells, in general, have the ability to maintain a reserve of energy in the form of some complex sugar. In the case of vegetables, the polysaccharide is starch, while in animals, the reserve form is glycogen.
The other, and last, is the size of cytoplasmic vacuoles. Both groups have this structure, however, in plant cells the vacuoles are generally large and can reach most of the cell volume, while in animals it is very small.
However, although there are several similarities between the different eukaryotic cells, there are characteristic differences between them that serve to classify the groups.
Finally, plants are extremely important for life because they participate in the “recycling” of the oxygen present in the environment and because they form the “base” of the food chain (ancient food pyramid) because they are producer beings, initial individuals in the flow of life Energy.