The nature of mushrooms has always raised many questions. In this article, we will try to deal with this and learn about the structural features of fungal cells.
What are mushrooms: plants or animals?
Even in the first half of the 20th century, mushrooms were classified as plants. Detailed studies have shown that they do not have the main feature of plants, namely the ability to photosynthesis, but they have much in common with animals. But this claim has also been refuted. In 1969, scientists came to the conclusion that the structure of fungal cells has its own unique features, which means that they should be attributed to a separate kingdom of wildlife.
Traditionally, the science of mycology is a branch of botany. Like most organisms, fungi belong to the super-kingdom of eukaryotes, or nuclear. Their peculiarity lies in the synthesis of qualities that are inherent in other living beings. Like plants, they do not have arms, legs, eyes, independent movement is also difficult for them. At the same time, fungi lack the ability to produce organic substances. Like animals, they consume them prepared.
This is one of the most diverse biological groups. Count the total number of species thatare included in this realm, it is difficult even for specialists. The numbers range from 300 thousand to several million. Mushrooms are part of all terrestrial and aquatic ecosystems.
Structure of fungal cells
The average size of a fungal cell in diameter is from 10 to 100 microns. Outside, it is enveloped by a strong shell, or cell wall. It consists of polysaccharides, lipids, phosphates, simple sugars, proteins, chitin and other substances. Inside, the wall is covered with a plasma membrane, which is responsible for metabolism and maintaining pressure.
The membrane is filled with fluid - the cytoplasm, which contains all the organelles. In the form of small particles in the cytoplasm is glycogen with a supply of nutrients. The basis of the cell is the nucleus, it contains genetic information. There may be several of them, depending on the type of fungus. Sometimes there is a nucleolus in the nucleus.
The structure of fungal cells is also characterized by the presence of vacuoles, centrioles, mitochondria, lobas. They contain the Golgi apparatus along with its various derivatives, such as phagosomes and lysosomes. The main task of all its components is the chemical rearrangement of secretion products. The endoplasmic reticulum is represented in the fungal cell by an extensive network of tubules and tubules that perform many functions. Among them - the accumulation of carbohydrates, the neutralization of poisons, the synthesis of hormones.
Scheme of the structure of the fungus cell is presented to your attention above.
Distinctive features in the structure
Together withIn plants and animals, fungi are classified as eukaryotes due to the presence of nuclei in their cells. In this regard, the cellular structure of these organisms is similar. Animals and plants have the most different composition, while the structure of fungal cells is something in between.
They, like plants, have a hard cell wall. Only it does not consist of cellulose, but of chitin, which is present in some animals (crayfish, insects, etc.). Fungi do not have chloroplasts and cannot carry out photosynthesis. Like plants, fungal cells contain vacuoles, and glycogen instead of starch.
The main common feature of fungi and some animals is the presence of chitin, as well as the accumulation of the polysaccharide glycogen as a nutrient. Representatives of both kingdoms have heterotrophic nutrition. Animal cells, unlike fungi, do not have vacuoles and a dense cell wall, except for a protective membrane.
Mold mushrooms
Among the huge variety of fungi are molds, scientifically - oomycetes. They are no different from other types of mold cells. The structure of these organisms has external differences. They do not have a pronounced fruiting body (reproductive organ), like cap mushrooms. All that can be seen with the naked eye is the highly branched mycelium, which in the cap fungus usually hides underground. The fruiting body of the mold is weakly expressed.
The main distinguishing feature is the microscopic size. These organisms are widely distributed throughout the world. Mold has even been found in the ice of Antarctica. These fungi reproduce by spores and are especially fond of moisture. They are characterized by high survival and adaptability to various environmental factors. Even radiation doesn't kill mold. There are species that can cause great harm to humans and animals (aspergillosis, etc.), and some are used as antibiotics (penicillin, cyclosporine).
Yeast
One type of mushroom is yeast. Unlike cap and mold fungi, they usually do not form mycelium. Reproduction of this species does not occur by spores, as in their "relatives", but by a vegetative method using division or budding. Some varieties do form mycelium, which can break down into single cells.
Yeast has the ability to decompose sugar into carbon dioxide and alcohol. This process is called fermentation. When it is implemented, the necessary energy for the life of the fungus is released. Fermentation helps raise the dough, making it porous, which is why it is often used in cooking.
Yeast is demanding on environmental conditions. For them, the presence of sugar in the substrate is important. They are common on the surface of fruits and leaves, in natural reservoirs and soils. Some species live in the intestines of insects that feed on wood.
