This term has other meanings, see Competition. Competition in biology, any antagonistic relationship associated with the struggle for existence, for dominance, for food, space and other resources between organisms or species ... Wikipedia

- (from Latin mensa meal) a type of interspecific relationship in which one species, called amensal, undergoes growth and development inhibition, and the second, called an inhibitor, is not subject to such tests. Antibiosis and ... ... Wikipedia

- (from Latin com “with”, “together” and mensa “table”, “meal”; literally “at the table”, “at the same table”; earlier companionship) a way of coexistence (symbiosis) of two different types living organisms in which one population benefits ... Wikipedia

- (from other Greek ἀντι against, βίος life) antagonistic relations of species, when one organism limits the capabilities of another, the impossibility of coexistence of organisms, for example, due to intoxication by some organisms (antibiotics, ... ... Wikipedia

This term has other meanings, see Symbiosis (meanings). clown fish and sea ​​anemone organisms coexisting in mutualistic symbiosis ... Wikipedia

- (Late Lat. organismus from Late Lat. organizo I arrange, I give a slender appearance, from other Greek ὄργανον a tool) a living body that has a set of properties that distinguish it from inanimate matter. As a separate individual organism ... ... Wikipedia

"Predator" redirects here; see also other meanings. "Predators" redirects here; see also other meanings ... Wikipedia

Between two ants of the species Oecophylla longinoda. Thailand. Trophallaxis ... Wikipedia

Co-evolution of biological species interacting in an ecosystem. Changes that affect any traits of individuals of one species lead to changes in another or other species. The first to introduce the concept of co-evolution was N. V. Timofeev Resovsky ... ... Wikipedia

This article or section has a list of sources or external links, but the sources of individual statements remain unclear due to the lack of footnotes ... Wikipedia

Books

• Semiotic theory of biological life, N. A. Zarenkov. Is it possible to understand what life is, limited to the study of the flesh of organisms - the signs of life: molecules, chromosomes, cells, tissues and organs? This book substantiates the negative answer to ...

Species of any organisms living in the same territory and in contact with each other enter into different relationships with each other. The position of the species in different forms of relationships is indicated by conventional signs. The minus sign (?) denotes an adverse effect (individuals of the species are oppressed). The plus sign (+) denotes a beneficial effect (individuals of the species benefit). The zero sign (0) indicates that the relationship is indifferent (no influence).

Biotic connections? relationships between different organisms. They can be direct (direct impact) and indirect (indirect). Direct connections are carried out with the direct influence of one organism on another. Indirect links are manifested through the influence on external environment or another kind.

Thus, all biotic bonds can be divided into 6 groups:

1 Neutralism - populations do not affect each other (00);

2a. Protocooperation - populations have mutually beneficial relationships (++) (Interaction with each other is useful for both populations, but is not mandatory);

2c. Mutualism - populations have mutually beneficial relationships (++) (Required interaction, useful for both populations);

3. Competition - relationships are harmful to both species (? ?);

5. Commensalism - one species benefits, the other does not experience harm (+0);

6. Ammensalism - one species is oppressed, the other does not benefit (? 0);

Interaction types

In nature, cohabitation of two or more species is often found, which in some cases becomes necessary for both partners. Such cohabitation is called the symbiotic relationship of organisms (from the combination of sim? together, bio? life) or symbiosis. The term "symbiosis" is general, it refers to cohabitation, a prerequisite of which is living together, a certain degree of cohabitation of organisms.

A classic example of symbiosis are lichens, which are a close mutually beneficial cohabitation mushrooms and algae.

A typical symbiosis is the relationship between termites and single-celled ones living in their intestines? flagella. These protozoa produce an enzyme that breaks down fiber into sugar. Termites do not have their own cellulose-digesting enzymes and would die without symbionts. And flagellates find favorable conditions in the intestines that contribute to their survival. A well-known example of symbiosis? cohabitation of green plants (primarily trees) and fungi.

A close mutually beneficial relationship, in which the presence of each of the two partner species becomes mandatory, is called mutualism (++). Such, for example, are the relationships of highly specialized plants for pollination (figs, bathing suit, Datura, orchids) with insect species that pollinate them.

A symbiotic relationship in which one species gains some benefit without harming or benefiting the other is called commensalism (+0). The manifestations of commensalism are diverse, therefore, a number of variants are distinguished in it.

Freeloading? consumption of the host's leftover food. This, for example, is the relationship between lions and hyenas, picking up the remains of half-eaten food, or sharks with sticky fish. Companionship? consumption of different substances or parts of the same food. Example? relationships between different types of soil bacteria-saprophytes that process different organic matter from decayed plant residues, and higher plants that consume the mineral salts formed in the process. Housing? the use by one species of others (their bodies, their dwellings) as shelter or dwelling. Is this type of relationship widespread in plants? an example is lianas and epiphytes (orchids, lichens, mosses) that settle directly on the trunks and branches of trees.

In nature, there are also such forms of relationships between species when coexistence is not mandatory for them. These relationships are not symbiotic, although they play an important role in the existence of organisms. An example of mutually beneficial relationships is proto-cooperation (literally: primary cooperation) (++), which can include the spread of seeds of some forest plants by ants or pollination by bees of different meadow plants.

If two or more species use similar ecological resources and live together, there may be competition between them (? ?), or a struggle for possession of the necessary resource. Competition occurs where ecological resources are in short supply, and rivalry inevitably arises between species. At the same time, each species experiences oppression, which negatively affects the growth and survival of organisms, and the number of their populations.

Competition is extremely widespread in nature. For example, plants compete for light, moisture, nutrients soil and, consequently, for the expansion of its territory. Animals fight for food resources and for shelters (if they are in short supply), that is, ultimately, also for territory. Competition weakens in areas with a sparse population represented by a small number of species: for example, in arctic or desert regions there is almost no competition for plants for light.

Predation (+ ?) ? a type of relationship between organisms in which representatives of one species kill and eat representatives of another. Predation? one of the forms of food relations.

If two species do not affect each other, what is it? neutralism (00). In nature, true neutralism is very rare, since indirect interactions are possible between all species, the effect of which we do not see due to the incompleteness of our knowledge.

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Question 1. Define the main forms of interactions of living organisms.
1. Symbiosis (cohabitation)- a form of relationship in which both partners or one of them benefit from the interaction without causing harm to the other.
2. Antibiosis- a form of relationship in which both interacting populations (or one of them) experience a negative impact.
3. Neutralism- a form of relationship in which organisms living in the same territory do not directly influence each other. They turn them into simple compounds.

Question 2. What forms of symbiosis do you know and what are their features?
There are several forms of symbiotic relationships, characterized by varying degrees of dependence of partners.
1. Mutualism- a form of mutually beneficial cohabitation, when the presence of a partner is a prerequisite for the existence of each of them. For example, termites and flagellate protozoa that live in their intestines. Termites themselves cannot digest the cellulose they feed on, and flagellates receive food, protection and a favorable microclimate; lichens, which are an inseparable cohabitation of a fungus and algae, when the presence of a partner becomes a condition for the life of each of them. Hyphae of the fungus, braiding the cells and threads of algae, receive substances synthesized by algae. Algae extract water and minerals from fungal hyphae. In a free state, lichen fungi do not occur and are able to form a symbiotic organism only with a certain type of algae.
Higher plants also enter into a mutually beneficial relationship with fungi. Many grasses and trees develop normally only when soil fungi settle on their roots. The so-called mycorrhiza is formed: root hairs do not develop on the roots of plants, and the mycelium of the fungus penetrates into the root. Plants receive water and mineral salts from the fungus, and the fungus, in turn, receives carbohydrates and other organic substances.
2. Cooperation - mutually beneficial coexistence we see different representatives, but which, however, is obligatory. For example, hermit crab and anemone soft coral.
3. Commensalism(companionship) - a relationship in which one species benefits, while the other is indifferent. For example, jackals and hyenas, eating up the remnants of food for large predators - lions; pilot fish.

Question 3. What is the evolutionary significance of symbiosis?
Symbiotic relationships allow organisms to most fully and effectively master the environment, they are the most important components of natural selection involved in the process of species divergence.

Nature is beautiful and varied. Living on the same planet, plants and animals had to learn to coexist with each other. The relationship between organisms is not an easy but interesting topic that will help you better understand the world around you.

Relationship types

Eat different kinds relationships among themselves. But scientists divide them into three large groups.

The first group combines all those types of relationships between organisms that can be called positive, the result of which helps two organisms to exist without contradictions.

The second group includes those types of relationships that are called negative. As a result of the interaction of two organisms, only one benefits, while the other is oppressed. Sometimes the latter may even die as a result of such relationships. This group also includes such an interaction of organisms that negatively affects both the first and second individuals.

The third group is considered the smallest. This group includes relationships between organisms that bring neither benefit nor harm to both parties.

Positive types of relationships between organisms

In order to exist in the world, you need to find allies and helpers. This is what many plants and animals do during their lifetime. evolutionary development. The result is a relationship where both parties benefit from the relationship. Or those relationships that are beneficial only to one side, and they do not harm the other.

Positive relationships, also called symbiosis, come in many forms. Currently, cooperation, mutualism and commensalism are distinguished.

Cooperation

Cooperation is such a relationship between living organisms when both parties benefit. Most often, this benefit lies in the extraction of food. But sometimes one of the parties receives from the other not only food, but also protection. Such relationships between organisms are very interesting. Examples can be seen in the animal kingdom in different parts planets.

One of them is the cooperation of hermit crab and sea anemone. Thanks to anemones, cancer finds a home and protection from other inhabitants of the water. Without a hermit crab, an anemone cannot move. But cancer allows you to expand the radius of the search for food. In addition, what the anemone does not eat will sink to the bottom and get cancer. This means that both parties benefit from this relationship.

Another example was the relationship between rhinos and bullock birds. Such relationships between organisms allow one of the parties to find food. Cowbirds eat insects that live in abundance on the huge rhinoceros. Rhinos also benefit from neighbors. Thanks to these birds, he can lead healthy life and don't worry about insects.

Commensalism

Commensalism is those relationships between organisms in ecosystems when one of the organisms benefits, and the second does not experience inconvenience from these relationships, but does not benefit either. This type of relationship is also referred to as cheating.

Sharks are terrible marine predators. But for stick fish, they become a chance to survive and protect themselves from other aquatic predators, which are weak compared to sharks. Stick fish benefit from sharks. But they themselves do not bring them any benefit. At the same time, there is no harm. For the shark, such relationships go unnoticed.

In the burrows of rodents you can find not only cubs, but also a huge number of different insects. The hole created by the animal becomes their home. It is here that they find not only shelter, but also protection from those animals that love to feast on them. In a rodent hole, an insect is not afraid. In addition, here they can find enough food to lead a life without trouble. Rodents do not experience any difficulties from these types of relationships.

Negative types of relationships between organisms

Living together on the planet, animals can not only help each other, but also cause harm. It is not easy to learn these relationships between organisms. The table will help schoolchildren and students.

Predation

What is predation, anyone can tell without preparation. This is the relationship between organisms when one side benefits and the other suffers. In order to better understand who feeds on whom, one can compose And then it is easy to find out that many herbivores become the food of other animals. At the same time, predators can also be someone's food.

Despite the fact that hedgehogs are often depicted in pictures with apples and mushrooms, they are predators. Hedgehogs feed on small rodents. But they don't feel safe either. They can be eaten by foxes. In addition, foxes, like wolves, feed on hares.

Despite the bloodthirsty predators hunting for weaker animals day and night, competition is considered the most cruel type of relationship between organisms. After all, these include the struggle for a place under the sun among representatives of the same species. And each species has its own means of obtaining the required amount of food or better housing.

Stronger and more dexterous animals win in the fight. Strong wolves get good prey, while others are left to either eat other, less satisfying animals, or die of hunger. There is a similar struggle between plants to get as much moisture or sunlight as possible.

Neutral relationship

There are also such types of relationships between organisms when both parties receive neither benefit nor harm. Despite the fact that they live in the same territory, absolutely nothing unites them. If one of the parties of these relationships disappears from the face of the planet, then this will not directly affect the other side.

Yes, in warm countries different herbivores feed on the leaves of the same tree. Giraffes eat those leaves that are on top. They are the most juicy and delicious. And other herbivores are forced to feed on the remains growing below. Giraffes do not interfere with them and do not take away food. After all, low animals will not be able to reach those leaves that are eaten by high ones. And tall, it makes no sense to bend down and take food from others.

Eat different forms relationships between organisms. And learning them all is not easy. But it is important to remember that everything in nature is interconnected. Most often, animals and plants affect each other positively or negatively, less often they do not affect each other at all. But even if they are not directly related, this does not mean that the disappearance of one cannot lead to the death of the other. The relationship between organisms is an important part of the world around us.

Types of relationships between organisms

Animals and plants, fungi and bacteria do not exist in isolation from each other, but enter into complex relationships. There are several forms of interaction between populations.

Neutralism

The cohabitation of two species in the same territory, which has neither positive nor negative consequences for them.

In neutralism, cohabiting populations of different species do not affect each other. For example, it can be said that a squirrel and a bear, a wolf and a cockchafer do not directly interact, although live in the same forest.

Antibiosis

When both interacting populations or one of them experience a harmful, overwhelming influence.

Antagonistic relationships can manifest themselves as follows:

1. Competition.

A form of antibiotic relationship in which organisms compete with each other for food resources, a sexual partner, shelter, light, etc.

In competition for food, the species that reproduces the fastest wins. Under natural conditions, competition between closely related species weakens if one of them moves to a new food source (that is, they occupy a different ecological niche). For example, in winter, insectivorous birds avoid competition due to different places for searching for food: on the trunk of trees, in shrubs, on stumps, on large or small branches.

Displacement of one population by another: In mixed crops of different types of clover, they coexist, but competition for light leads to a decrease in the density of each of them. Thus, competition arising between close species can have two consequences: either the displacement of one species by another, or different ecological specialization of species, which makes it possible to coexist.

Suppression of one population by another: For example, antibiotic-producing fungi inhibit the growth of microorganisms. Some plants that can grow in nitrogen-poor soils secrete substances that inhibit the activity of free-living nitrogen-fixing bacteria, as well as the formation of nodules in legumes. In this way, they prevent the accumulation of nitrogen in the soil and the colonization of it by species that need a large amount of it.

3. Amensalism

A form of antibiotic relationship in which one organism interacts with another and suppresses its vital activity, while itself does not experience any negative influences from the suppressed one (for example, spruce and plants of the lower tier). A special case is allelopathy - the influence of one organism on another, in which the waste products of one organism are released into the external environment, poisoning it and making the other unsuitable for life (common in plants).

5 Predation

This is a form of relationship in which an organism of one species uses members of another species as a food source once (by killing them).

Cannibalism - a special case of predation - killing and eating their own kind (found in rats, brown bears, humans).

Symbiosis

A form of relationship in which the participants benefit or at least do not harm each other from cohabitation. Symbiotic relationships also come in a variety of forms.

1. Protocooperation - mutually beneficial, but optional coexistence of organisms, from which all participants benefit (for example, hermit crab and sea anemone).

2. Mutualism is a form of symbiotic relationship in which either one of the partners or both cannot exist without a cohabitant (for example, herbivorous ungulates and cellulose-destroying microorganisms).

Lichens are an inseparable cohabitation of a fungus and algae, when the presence of a partner becomes a condition for the life of each of them. Hyphae of the fungus, braiding the cells and threads of algae, receive substances synthesized by algae. Algae extract water and minerals from fungal hyphae.

Many grasses and trees develop normally only when soil fungi (mycorrhiza) settle on their roots: root hairs do not develop, and the mycelium of the fungus penetrates into the root. Plants receive water and mineral salts from the fungus, and it, in turn, receives organic substances.

3. Commensalism - a form of symbiotic relationship in which one of the partners benefits from cohabitation, while the other is indifferent to the presence of the first. There are two types of cohabitation:

Lodging (some sea anemones and tropical fish). The fish stuck, sticking to large fish (sharks), uses them as a means of transportation and, in addition, feeds on their garbage.

The use of structures and body cavities of other species as shelters is widespread. In tropical waters, some fish hide in the cavity of the respiratory organs (water lungs) of holothurians (or sea cucumbers, a detachment of echinoderms). The fry of some fish find shelter under the umbrella of jellyfish and are protected by their stinging threads. As protection for developing offspring, fish use a strong shell of crabs or bivalve mollusks. Eggs laid on the gills of a crab develop under conditions of ideal supply. clean water passed through the gills of the host. Plants also use other species as habitats. These are the so-called epiphytes - plants that settle on trees. It can be algae, lichens, mosses, ferns, flowering plants. Woody plants serve as a place of attachment for them, but not a source of nutrients.

Freeloading (large predators and scavengers). For example, hyenas follow lions, picking up the remains of prey that they have not eaten. There can be various spatial relationships between partners. If one partner is outside the cells of the other, they talk about ectosymbiosis, and if inside the cells - endosymbiosis.

EXAMINATION TICKET No. 4
	Types of nutrition of living organisms.
	Theories of the origin of life.

Types of nutrition of living organisms:

There are two types of nutrition of living organisms: autotrophic and heterotrophic.

Autotrophs (autotrophic organisms) - organisms that use carbon dioxide as a source of carbon (plants and some bacteria). In other words, these are organisms capable of creating organic substances from inorganic ones - carbon dioxide, water, mineral salts.

Heterotrophs (heterotrophic organisms) - organisms that use organic compounds (animals, fungi and most bacteria) as a carbon source. In other words, these are organisms that are not able to create organic substances from inorganic ones, but need ready-made organic substances.

Some living beings, depending on the habitat conditions, are capable of both autotrophic and heterotrophic nutrition. Organisms with a mixed type of nutrition are called mixotrophs. Mixotrophs - organisms that can both synthesize organic substances from inorganic ones and feed on ready-made organic compounds (insectivorous plants, representatives of the euglenoid algae department, etc.)