Lesson summary "Forms of biotic relationships. Antibiotic relationships."

Predation. This is one of the most common forms, having great importance in self-regulation of biocenoses. Predators are animals (as well as some plants) that feed on other animals, which they catch and kill. The objects of hunting for predators are extremely diverse. Lack of specialization allows predators to use a wide variety of foods. For example, foxes eat fruit; bears pick berries and love to feast on the honey of forest bees. Red fox

Although all predators have preferred types of prey, the mass reproduction of unusual prey makes them switch to them. Thus, peregrine falcons obtain food in the air. But when mass reproduction After lemmings, falcons begin to hunt them, snatching prey from the ground. The ability to switch from one type of prey to another is one of the necessary adaptations in the life of predators. Peregrine Falcon

Predation is one of the main forms of struggle for existence and is found in all large groups of eukaryotic organisms. Already among unicellular organisms, eating individuals of one species by another is a common occurrence. Jellyfish paralyze with stinging cells any organisms that fall within the reach of their tentacles (in large forms up to 20-30 m in length), and eat them. Aurelia

Many centipedes, in particular the scolopendra, are also typical predators with extremely wide range victims: from insects to small vertebrates.

Large frogs attack chicks and can cause serious damage to waterfowl breeding. Snakes hunt amphibians, birds and small mammals. Often the objects of their hunt are not only adult birds, but also bird eggs. Bird nests, located both on the ground and on tree branches, are literally devastated by snakes. Already ordinary

A special case of predation is cannibalism - eating individuals of its own species, most often juveniles. Cannibalism is often found in spiders (females often eat males) and in fish (eating fry). Female mammals also sometimes eat their young. River perch

Predation is associated with the acquisition of resisting and escaping prey. When a peregrine falcon attacks birds, most victims die instantly from a sudden blow from the falcon's talons. Vole mice also cannot resist an owl or a fox. white owl

But sometimes the struggle between predator and prey turns into a fierce fight. Therefore, natural selection operating in a population of Predators will increase the efficiency of means of searching and catching prey. This purpose is served by the web of spiders, the poisonous teeth of snakes, and the precise attacking blows of mantises, dragonflies, snakes, birds and mammals. Complex behavior is developed, such as the coordinated actions of a pack of wolves when hunting deer. Cross spider

This includes protective coloring, various spikes and shell, adaptive behavior. When a predator attacks a school of fish, all individuals scatter. On the contrary, starlings, having noticed a peregrine falcon, huddle together in a dense group. The predator avoids attacking a dense flock, as it risks being injured. Large ungulates become circled when attacked by wolves. For wolves there is a chance to fight back. and slaughter an individual as a result of this behavior, the herd is significantly reduced. Therefore, they prefer to attack animals that are old or weakened by disease, especially those that have strayed from the herd. Mountain hare During the selection process, victims also improve their means of defense and avoidance of predators.

Similar behavior has developed in primates. When there is a threat of attack by a predator, females with cubs find themselves in a dense ring of males. In the evolution of the predator-prey relationship, there is constant improvement of both predators and their prey. Baboon family. php?image_id=199

Nitrogen requirements for plants growing on poor nutrients soils washed with water led to the emergence of a very interesting phenomenon in them. These plants have adaptations for catching insects. Thus, the leaf blades of the Venus flytrap, endemic to North Carolina (USA), have turned into valves with teeth. The valves slam shut as soon as the insect touches the sensitive hairs on the leaf blade. Venus flytrap. alog/indoor/ alog/indoor/

The sundew found in Russia has leaves collected in a basal rosette. The entire top side and edges of each leaf are covered with glandular hairs. In the center of the leaf the glandular hairs are short and long at the edges. The head of the hair is surrounded by a transparent droplet of thick sticky viscous mucus. Small flies or ants land or crawl onto the leaf and stick to it. The insect struggles, trying to free itself, but all the hairs of the disturbed leaf bend towards the prey, enveloping it in mucus. The edge of the leaf slowly curls up and covers the insect. The mucus secreted by the hairs contains enzymes, so the prey is quickly digested.

Feeding on animals, predation also occurs in fungi. Predatory mushrooms form trapping devices in the form of small oval or spherical heads located on short branches of the mycelium. However, the most common type of trap is adhesive three-dimensional nets consisting of large number rings formed as a result of branching hyphae. Often carnivorous mushrooms catch animals larger than themselves, for example roundworms. The trapping process is reminiscent of catching flies with sticky paper. Soon after the worm becomes entangled, the fungal hyphae grow inward and quickly fill the entire body. The whole process lasts about a day. In the absence of nematodes, fungi do not form traps. The emergence of a complex hunting apparatus is stimulated chemically by the waste products of worms.

Literature Zakharov V.B. General biology: Textbook. For class general education institutions. - M.: Bustard, 2004.

Antibiosis- a form of relationship in which both interacting populations or one of them experience a negative impact. The adverse effects of some species on others can manifest themselves in different forms.

Competition. One form of negative relationships between species is competition. This type of relationship occurs when two closely related species have similar needs. If such species live in the same territory, then each of them is at a disadvantage: the possibilities of acquiring food resources, breeding sites, etc. are reduced. Forms of competitive interaction can be very different - from direct physical struggle to peaceful coexistence. However, if two species with the same needs end up in the same community, sooner or later one competitor will displace the other. Charles Darwin considered competition one of the most important components the struggle for existence, which plays a large role in the evolution of species.

No matter how similar the needs of the species are, they still differ from each other in some way, just as their resistance to environmental factors - temperature, humidity, etc. - differs. For these reasons, the rate of reproduction of species will be different. With each generation, more and more food resources will be captured by individuals of a competitive species, while the other species will inevitably disappear.

Often competitors actively influence each other. In plants, this may be the interception of mineral salts and moisture by the root system, sunlight- leaves. In mixed crops of herbs, species with longer leaf petioles are advantageous. In mixed plantings of trees, fast-growing specimens will shade and suppress slow-growing trees.

Plants and animals can suppress competitors with the help of chemical substances. Fungi inhibit bacterial growth by producing antibiotics. In animals, there are cases of direct attacks by representatives of one species on another. As a result, the weaker competitor dies or seeks free territory.

One of the ways to regulate the population density of a given species in a biogeocenosis is to mark the territory occupied by an individual or family. The smell left by the animal serves as a signal warning that the territory is occupied.

As a result of competition in the biogeocenosis, only those species that were able to diverge in their requirements for living conditions coexist. For example, ungulates African savannas differently use pasture feed. Zebras pluck the tops of grass; antelopes feed on what zebras leave for them, choosing certain types of plants; gazelles pluck the shortest grasses, and toppy antelopes eat dry stems left behind by other herbivores.

Predation. This is one of the most common forms that is of great importance in the self-regulation of biocenoses. Predators are animals (as well as some plants) that feed on other animals, which they catch and kill. The objects of hunting for predators are extremely diverse. Lack of specialization allows predators to use a wide variety of foods. For example, foxes eat fruit; bears pick berries and love to feast on the honey of forest bees. Although all predators have preferred types of prey, the mass reproduction of unusual prey makes them switch to them. Thus, peregrine falcons obtain food in the air. But when lemmings reproduce en masse, falcons begin to hunt them, snatching prey from the ground.

The ability to switch from one type of prey to another is one of the necessary adaptations in the life of predators.

Many centipedes, in particular centipedes, are also typical predators with an extremely wide range of prey: from insects to small vertebrates. Large frogs attack chicks and can cause serious damage to waterfowl breeding. Snakes hunt amphibians, birds and small mammals. Often the objects of their hunt are not only adult birds, but also bird eggs. Bird nests, located both on the ground and on tree branches, are literally devastated by snakes.

Therefore, natural selection operating in a population of predators will increase the efficiency of means of searching and catching prey.

This purpose is served by the web of spiders, the poisonous teeth of snakes, and the precise attacking blows of mantises, dragonflies, snakes, birds and mammals. Complex behavior is developed, such as the coordinated actions of a pack of wolves when hunting deer.

Prey, through the process of selection, also improve their means of defense and avoidance of predators. This includes protective coloration, various spines and shells, and adaptive behavior. When a predator attacks a school of fish, all individuals scatter, which increases their chances of surviving. On the contrary, starlings, having noticed a peregrine falcon, huddle together in a dense group. The predator avoids attacking a dense flock, as it risks being injured. Large ungulates become circled when attacked by wolves. For wolves, the likelihood of repelling and killing an individual as a result of this herd behavior is significantly reduced. Therefore, they prefer to attack animals that are old or weakened by disease, especially those that have strayed from the herd.

Similar behavior has developed in primates. When there is a threat of attack by a predator, females with cubs find themselves in a dense ring of males.

In the evolution of the predator-prey relationship, there is constant improvement of both predators and their prey.

The need for nitrogen in plants growing in nutrient-poor soils washed with water has led to the emergence of a very interesting phenomenon. These plants have adaptations for catching insects. Thus, the leaf blades of the Venus flytrap, endemic to North Carolina (USA), have turned into valves with teeth. The valves slam shut as soon as the insect touches the sensitive hairs on the leaf blade. The round-leaved sundew, found in Russia, has leaves collected in a basal rosette. The entire upper side and edges of each leaf are covered with glandular hairs. In the center of the leaf the glandular hairs are short, along the edges they are long. The head of the hair is surrounded by a transparent droplet of thick sticky viscous mucus. Small flies or ants land or crawl onto the leaf and stick to it. The insect struggles, trying to free itself, but all the hairs of the disturbed leaf bend towards the prey, enveloping it in mucus. The edge of the leaf slowly curls up and covers the insect. The mucus secreted by the hairs contains enzymes, so the prey is quickly digested.

Feeding on animals - predation - is also found in fungi. Predatory mushrooms form trapping devices in the form of small oval or spherical heads located on short branches of the mycelium. However, the most common type of trap is adhesive three-dimensional networks consisting of a large number of rings formed as a result of the branching of hyphae. Often, predatory fungi catch animals that are larger than them, such as roundworms. The trapping process is reminiscent of catching flies with sticky paper. Soon after the worm becomes entangled, the fungal hyphae grow inward and quickly fill the entire body. The whole process lasts about a day. In the absence of nematodes, fungi do not form traps. The emergence of a complex hunting apparatus is stimulated chemically by the waste products of worms.

Rice. 25.14.

Rice. 25.15.A - Finn; B - egg

Rice. 25.16.

Below - stages of development of malarial plasmodium

Rice. 25.17. Elephantiasis in humans:

A- sick; B- filamentum - the causative agent of the disease

Biological control methods are becoming increasingly popular higher value and in the future will allow to reduce the use of pesticides in agriculture.

Actually antibiosis. Each of us is familiar with an example of a typical antibiosis from the example of fungi that produce special biologically active substances - antibiotics. It is from them that the whole group of relationships gets its name: antibiotics secreted in environment, reduce the intensity of life activity pathogenic bacteria or even kill them. Another example of antibiosis is the release by a plant organism of phytoncides that have a bactericidal effect (from the Greek. bakterion - wand and lat. cido - kill) and protect against viruses, bacteria and pathogenic fungi.

Neutralism- a form of relationship in which organisms living together in the same territory do not influence each other. When an individual is neutral different types are not directly related to each other, but, forming a biocenosis, depend on the state of the community as a whole. For example, squirrels and moose in the same forest have no contact with each other, but the suppression of the forest by drought affects each of them, although to varying degrees.

All of the listed forms of biological connections between species serve as regulators of the number of animals and plants in the biocenosis, determining the degree of its stability; at the same time, the richer species composition biocenosis, the more stable the community as a whole.

Anchor points

Multiplicity of forms of antibiotic, symbiotic and neutral relations between organisms within communities forms biocenoses.
Symbiosis, neutralism and antibiosis are characteristic of the interaction of organisms of all kingdoms of living nature.
The neutral nature of the relationships between organisms indicates only the absence of direct contacts between organisms.

Forms biotic relationships. Antibiotic relationships.

Lesson in 11th grade

Lesson objectives:

Continue to deepen and expand knowledge about the diversity of relationships
between organisms based on studying the characteristics of antibiotic relationships;

To consolidate and generalize students’ knowledge about the forms of positive and antibiotic
relationships.

Equipment:

Flashcards with images of living organisms, crossword puzzle, tables, diagrams

During the classes:

Organizing time.

Learning new material.

Teacher's story with elements of conversation and independent work students from
textbook in search of examples of forms of antibiotic relationships.

(paragraph 17.4.2.)

Antibiosis is a relationship that leads to a negative effect of certain species on other.

1) Predation is one of the most common forms of antibiosis, having
self-regulation of biogeocenosis is of great importance. (Students from this section to
Notebooks note examples of predation in plants and animals.

Predation

Plants Animals

First stage:

A) Ecological mysteries: Long rejected by selection,Don't knock your feet off!Live, strong brothers,And I can’t escape fate.

(Predator-prey)

You and I are in one bond, like Friendly family, It has long been unclear where you are and where I am.

(Symbiosis)

I wish you many years of life, You don’t know about me at all! I will find dinner and lunch,As long as you are in my destiny.

Let him, as powerful as a rock, not scare me off at all!

If only from the master's tableI got something.

(Freeloading)

Second phase:

Using flashcards with magnets lying on the table select shapesvarious biotic relationships and attach it to a magnetic board, afternaming the type of relationship.

Third stage:

Here are some of the plants and animals you may know. Write them downnames in two columns according to ecological role these organisms innature.

Role in nature

Plants

Animals

Lion, roundworm, broomrape, sundew, flea, spider, orchid, jackal, rafflesia, dragonfly,
sea anemone, dodder, mycorrhiza, pilot, sperm whale, Venus, flytrap, pinworm, cancer-

hermit, lichen, sticky fish.

Fourth stage: Solve the crossword puzzle

4. 1) Final synthesis of knowledge.

Types of interspecific interactions.

Relationship type

The essence of relationships

Symbiosis

Mutually beneficial cohabitation organisms

Cooperation

Species form mutually beneficial communities

Commensalism

The commensal benefits, but the owner is neutral

Mutualism

Mandatory mutually beneficial cooperation

Predation

One species kills prey by feeding on it

One of the species uses the host as a habitat, a source of food

2) Knowledge assessment

5. Homework: Paragraph 17.4.1

Horizontally:

I. An insect that lays eggs in the larvae of another insect

5. A form of biotic relationships in which species and individuals do not influence each other in any way
friend

Use of one species by another without harming it

The simplest type of symbiotic relationship

Carnivorous organism, consumer of the 2nd order.
Vertically:

Fish - commensal, companion of the shark

Predator species

A pioneer organism in which representatives of two kingdoms of nature coexist peacefully

Type of biotic relationship

The form of biotic relationships of closely related species with similar ecological
needs

9. Human helminth known since ancient times

12. The plant is a predator living in a swamp.

Application:

Vertically: 1 – stuck, 2 – hunter, 3 – lichen, 4 – symbiosis, 6 – mosquito, 7 – competition, 9 – roundworm, 10 – host, 12 – sundew.

Antibiosis is a form of relationship in which both interacting populations or one of them experiences a negative effect. The adverse effects of some species on others can manifest themselves in different forms.

Predation.

This is one of the most common forms, which are of great importance in the self-regulation of biocenoses. Predators are animals (as well as some plants) that feed on other animals, which they catch and kill. The objects of hunting for predators are extremely diverse. The lack of specialization allows predators to use a wide variety of foods. For example, foxes eat fruit; bears pick berries and love to feast on the honey of forest bees. Although all predators have preferred types of prey, the mass reproduction of unusual prey makes them switch to them. Thus, peregrine falcons obtain food in the air. But when lemmings reproduce en masse, falcons begin to hunt them, snatching prey from the ground. The ability to switch from one type of prey to another is one of the necessary adaptations for predators.

Competition.

One form of negative relationships between species is competition. This type of relationship occurs when two closely related species have similar needs. If such species live in the same territory, then each of them is at a disadvantage: the possibilities of acquiring food resources, breeding sites, etc. are reduced. Forms of competitive interaction can be very different - from direct physical struggle to peaceful coexistence. However, if two species with the same needs end up in the same community, sooner or later one competitor will displace the other. Charles Darwin considered competition to be one of the most important components of the struggle for existence, playing a large role in the evolution of species. As a result of competition in the biogeocenosis, only those species that were able to diverge in their requirements for living conditions coexist. For example, ungulates of the African savannah use pasture food in different ways. Zebras pluck the tops of grass; antelopes feed on what zebras leave for them, choosing certain types of plants; gazelles pluck the lowest grasses, and toppy antelopes eat dry stems left behind by other herbivores.

Neutralism.

Neutrality is a form of relationship in which organisms living together in the same territory do not influence each other. With neutralism, individuals of different species are not directly related to each other, but, forming a biocenosis, depend on the state of the community as a whole. For example, squirrels and moose in the same forest have no contact with each other, but the suppression of the forest by drought affects each of them, although to varying degrees.

All of the listed forms of biological connections between species serve as regulators of the number of animals and plants in the biocenosis, determining the degree of its stability; Moreover, the richer the species composition of the biocenosis, the more stable the community as a whole.

AND living organisms can influence each other positive influence (symbiotic relationship) bad influence (antibiotic relationship) or not influence each other (neutralism).

Neutralism - cohabitation of two species in the same territory, which has neither positive nor negative consequences for them (for example, squirrels and moose).

Symbiotic relationship - such relationships between organisms in which the participants benefit from cohabitation or at least do not harm each other. There are protocooperation, mutualism, commensalism, etc.

Protocooperation - mutually beneficial, but not obligatory, coexistence of organisms from which all participants benefit (for example, hermit crab and sea anemone).

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

Commensalism - a form of symbiotic relationship in which one of the partners benefits from cohabitation, and the other is indifferent to the presence of the first. There are two forms of commensalism: synoikia , or tenancy(for example, some sea anemones and tropical fish) and trophobiosis , or freeloading(For example, large predators and scavengers).

Predation - a form of antibiotic relationship in which one of the participants (the predator) kills the other (the prey) and uses it as food (for example, wolves and hares). Cannibalism - special case predation - killing and eating their own kind (found in rats, brown bears, person).

Competition - a form of antibiotic relationship in which organisms compete with each other for food resources, a sexual partner, shelter, light, etc. There are interspecific And intraspecific competition.

Amensalism - a form of antibiotic relationship in which one organism acts on another and suppresses its vital activity, while it itself does not experience any negative influences from the suppressed one (for example, spruce and lower tier plants).

Anthropogenic factors - human activity leading either to a direct impact on living organisms or to a change in their habitat. At the same time, the impact of a person differs as biological organism and its economic activities (technogenic factors).

Lesson summary "Forms of biotic relationships. Antibiotic relationships."

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