Symbiosis: Definition, Meaning, Overview, Examples, Types

Symbiosis is the fundamental concept in biology describing a close and long-term association between two different living organisms, such as a symbiotic relationship. The definition of symbiosis in biology involves several kinds of associations, including mutualism, commensalism, and parasitism, which all describe different relationships. Symbiosis definition in biology stresses the interdependence among organisms that underlie the operation and evolution of ecosystems. There are symbiotic relationships found throughout nature, such as those that occur between the fungi and algae of lichens, or for the mycorrhizal fungi, which serve to enhance plant roots. This is the topic of the chapter Organisms And Population of Biology.

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This Story also Contains

1. What is Symbiosis?
2. Types of Symbiosis
3. Mutualism
4. Commensalism
5. Parasitism
6. Amensalism
7. Neutralism

What is Symbiosis?

Symbiosis refers to the mutual relationship between two different living organisms that can interact for an extended period depending on the kind of symbiosis. Symbiosis is said to be a close, long-term interaction between two different species. This kind of relationship is commonly known as a symbiotic relationship.

Symbiosis depends on the kind of interaction involved between species, such as mutualism, where both species benefit commensalism, where one benefits and does not affect the other and parasitism, where one species benefits at the expense of another. Symbiotic relations are important for the interpretation of ecosystems because they put across the idea that they are interconnected and dependent on each other.

Lichens are an example of a symbiotic association between fungi and algae, mycorrhizal fungi and plant roots, and clownfish and sea anemones. In general, symbiosis biology helps study how such interactions influence survival, reproduction, and adaptation. In ecology, the role of symbiosis is underscored in shaping ecosystems and driving evolution.

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Types of Symbiosis

The types of symbiosis are described below-

Mutualism

A symbiotic relationship is best characterised when both the involved species benefit from the arrangement, and one such form of symbiotic relationship is mutualism. Such a relationship can also improve the existence and breeding of both species. An example to well understand is that of the bee and the flower. Bees feed on honey that is collected from flowers and in so doing they transfer pollen needed for the production of seeds onto the flowers.

Mutualistic Relationship between Bees and Flowers

Commensalism

Commensalism is another form of showing a symbiotic relationship that is inter-species and in it one of the species benefits while the other remains unbothered in any way. An example is the bit between the barnacles and the whales. Whale lice are parasitic creatures that cling to the whale's skin to be granted a space to live at the same time, the whale is not harmed.

Commensal relationship between Barnacles and Whales

Parasitism

Symbiosis is the living together of two organisms different organisms living together especially with one of them being harmed or benefited. Parasitism is a type of symbiosis where one organism called the parasite benefits while the other one called the host is harmed. Such a relationship most likely hurts the host organism. An example is the association of fleas and dogs. The flea is a parasite that has a host and in this case, the host is the dog and feeds on the dog’s blood leading to uneasiness and even other health complications for the host.

Parasitic relationship between Flea and Dog

Amensalism

Amensalism is the type of symbiosis in which one of the species is harmed or even killed with no impact on the other partner. An example is the discharge of chemical substances by some plants to retard the growth of other encroaching plants like the black walnut tree synthesizes jungle.

Comparison of Amensalism with other forms of symbiosis

Neutralism

Neutralism is quite similar to neutralism, in which the two species tolerate each other’s presence and do not interact. It is the most limited because it is a rarity in most relations since no relation is completely free of any effect. An example might be a spider living with a cactus in the desert, in which case the two are not enemies.

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