Symbiosis is a form of relationship in which both organisms benefit from each other. The organism that lives in symbiosis is a symbiont.

Types of symbiosis

In biology, the term symbiosis can be used in two different meanings. As already mentioned, this is a form of cohabitation beneficial to everyone. However, in biology there is an older definition - mutualism. In any case, the word "symbiosis" in 1879 was introduced by the German botanist and microbiologist Heinrich Anton de Bari. The term was meant as the beneficial existence of different organisms, regardless of whether it is beneficial to them or not. Symbiosis was divided into:

• Parasitism (existence is beneficial for one roommate, the other suffers)
• Mutualism (mutually beneficial cohabitation).
• A third option, called commensalism, was also possible.

Commensalism

The third type denoted symbiosis, from which one organism benefited, and for the second it had a neutral value. This type of cohabitation can be divided into: zoohoria (animals and plants interact, animals help plants transfer seeds and fruits), syneykia (lodging, one doesn’t care, the second is beneficial), phoresia (a symbiosis of different species, in which a larger symbiont carries a smaller one) , epibiosis (the settling of one organism on another), epioikia (a symbiont lives on the surface of another without harming it), entoykia, paroikia. However, all these species have one similarity: one of the symbionts forms a special habitat for the other.

Symbiosis Examples

Mushrooms and trees

Many mushrooms (cep, boletus) have a close relationship with the roots of trees, having benefits for both themselves and the plant. With this symbiosis, the small roots of certain trees are braided with mycelium filaments (hyphae) that penetrate the roots and are located between cells. This formation is called mycorrhiza. Mycorrhiza was discovered by the Russian botanist Franz Mikhailovich Kamensky in 1879, and the name was given to this kind of symbiosis by the German scientist David Albertovich Frank.

If you literally translate this term, it really will reflect its essence, because it translates as - mushroom root. The benefit for the roots of the plant lies in the fact that the mycelium gives it water and the minerals dissolved in it, absorbed by it from the soil. This is necessary for the plant to develop the root system, because the mycelium can secrete vitamins and substances for this development. The plant supplies the fungus with ready-made organic substances, such as sugar, or root secretion, for the spores of the fungus.

Lichens

Thanks to symbiosis, groups of creatures can form, for example, lichens. They are formed by two organisms - cyanobacteria and fungus. The thallus is formed by intertwined fungal hyphae, and between them are cyanobacterial cells. There is an assumption that the autotrophic symbiont in most of these creatures is cyanobacteria nostok.

Algae and protists can also replace them. The benefit of this symbiosis is completely similar to mycorrhiza. Only here the mushroom, being part of the lichen, absolutely cannot do without an autotrophic symbiont, and the other - vice versa.Some sea anemones may also have mutual cohabitation, entering into symbiosis with invertebrates, hermit crabs, and even with fish (clown fish).

There is a very interesting suggestion that plastids also have a symbiotic origin, because cyanobacteria entered into symbiosis with eukaryotic cells. That is why eukaryotes have passed divided into autotrophs, and heterotrophs. They think similarly about mitochondria, only purple bacteria entered into symbiosis with eukaryotic cells.