What is symbiosis in biology? This is a kind of unspoken agreement between two or more individuals belonging to completely different species. Such cooperation may take the form of mutualism, commensalism and parasitism. Organisms in this case are called symbionts.
What is symbiosis in biology: definition
Symbiosis is any association between two different species of populations. His study is the quintessence of systems biology, which combines not only all levels of biological analysis, from molecular to environmental, but also studies the relationships between organisms in the three domains of life. The development of this area is still at an early stage, but in the near future the results will not be long in coming.
Types of symbiosis
What is symbiosis in biology (Grade 5)? Symbiosis is a relationship between two or more organisms living in close contact with each other. An interaction occurs when two species live in one place and one or both benefit from the other. Predation indirectly falls under this definition, since it can also be considered as a kind of symbiosis.
Indeed, one of the types of symbiosis, parasitism, is just a special form of predation. Despite this, ecologists classify predation and symbiosis as two different types of interactions. There are three main types of symbiotic interactions. This is mutualism, parasitism, commensalism.
Mutualism
Mutualism is one of the most famous and most environmentally significant types of symbiosis. Such relationships include, for example, insects and plants (pollination). Such cooperation is favorable and mutually beneficial for both parties. Insects, birds and even some mammals in the form of nectar get their livelihood. The plant, on the other hand, receives a great reproductive advantage, namely, they have the opportunity to transfer their pollen to other plants.
Since plants do not often end up together, it is quite problematic for them to perform reproductive function without intermediaries. In this case, symbiosis is simply vital for them, and in the full sense of the word. Without pollinators, many plants could simply gradually disappear. On the other hand, without pollinating plants, many insects themselves would be in great trouble. This is a truly mutually beneficial alliance.
Examples of symbiosis in biology are not limited to this. Another fascinating variant of beneficial cooperation can be seen in the relations of some species of ants and aphids. Aphids are tiny, soft insects that feed on the sap of plants, and as a waste they secrete a certain portion of sugar and water. This becomes suitable food for some species of ants. In turn, ants often transfer them to a new place, thus providing additional sources of nutrition.
Parasitism
What is symbiosis in biology? This cooperation, however, it can not always bring only benefit. Parasitic relations, in contrast to mutualistic ones, always imply inequality of interests. In fact, these relationships always take the form of a win-lose. Sometimes nothing happens with the loser, often this cooperation manifests itself in the form of discomfort, in some cases parasitism can be fatal.
There are many different types of parasites, but they are divided into two main types. Some arrange their home within the body of their owners, in which they live, while others feed on the surface.
The first type is called endoparasitis, these protozoa can cause diarrhea and severe pain, clog the lymph nodes and cause swelling of the extremities (elephantiasis). The second type, the so-called ectoparasites, also causes harm to its carrier. These include lice, mosquitoes and others, these pests receive shelter, food, and at this time their owner receives harm of varying degrees.
Commensalism
What is symbiosis in biology? First of all, this is cooperation. One of the most rare types of symbiosis in nature is commensalism. In this case, only one side benefits. The second from such an agreement is neither hot nor cold. Finding out his examples is a rather difficult task. However, a few examples can be given.
Commensalism is the union of two or more partners living together, where only one benefits from the partnership, and the other simply remains unharmed. For example, tiny inhabitants of the ocean depths, known as sticks and anemones, attach themselves in a special way to larger inhabitants (whales and sharks) and feed on any food at their expense. Missing tiny particles of food are immediately absorbed by "good" parasites. Actinia and the clown fish also have a similar relationship.
An example of commensalism can be shown by some desert lizards, who find their place of residence in abandoned rat or snake holes. Lizards receive shelter, while another animal does not receive anything in return.
What is symbiosis in biology? In simple words, we can say that this is a positive, negative or neutral cooperation between different types of organisms.