Presentation on 7th grade biology on the topic of oligochaetes. Class oligochaetes

CLASSIFICATION OF EARTHWORMS TYPE Annelida - Annelida SUBTYPE Belted - Clitellata CLASS Oligochaeta - ORDER Higher oligochaetes - Lumbricomorpha FAMILY Lumbricidae - Lumbricidae SPECIES Earthworm - Lumbricus terrestris

The most common types of earthworms are: 1. Tetrahedra earthworm (Eiseniella tetraedra) 2. Foul-smelling earthworm (Eisenia foetida) 3. Yellowish-green earthworm (Allophora chlorotica) 4. Reddish earthworm (Lumbricus rubellus) 5. Earthworm terrestrial or common (crawl) (Lumbricus terrestris)

Physical education lesson The bunny galloped (jumping on his toes). Let's look up at the trees. The bird flew by (we move our arms back and waved our wings). An owl sits on a tree - “uh, uh, uh” (while exhaling). The butterfly flies (arms to the sides and flapping its wings).

Close your eyes tightly (1-2-3), then open them and wave your eyelashes like a butterfly. Repeat 2-3 times. We came to the swamp. The heron is walking (walking with high knees). We are a little tired, let's rest, sit on a stump and breathe. Turn your chest out - inhale, bend forward - exhale.

Role in nature and human life It is hopelessly difficult The life of a simple worm: Straighten up - A bird will peck, Having seen it from afar. The worm listens sensitively - Where the shovel is there is a knock and a clink; The thoughts are the same: What if he cuts me in half for nothing! The fisherman collects the worms without further ado: Since the bait is not fake, the catch must be significant. When it rains, streams of water flood all the passages, It’s a pity that the holes are without constipation - How far is it from trouble? In a heavy downpour, barely alive, Poking its head into the ground, A crooked earthworm trudges through the streams.

“Archaeologists probably don’t know how much they owe to earthworms for preserving a large number of ancient objects, coins, gold jewelry, stone tools. Once on the surface of the earth, they are certainly buried for several years thanks to worms and are thereby reliably preserved.” “Archaeologists probably don’t know how much they owe to earthworms for preserving a large number of ancient objects, coins, gold jewelry, stone tools. Once on the surface of the earth, they are certainly buried for several years thanks to worms and are thereby reliably preserved.”

The role of earthworms in human life: 1. Humus (organic) fertilizer. 2. BAS (biologically active substances - essential amino acids, enzymes, vitamins) are used in: veterinary medicine, pharmacology, cosmetology, agriculture, biotechnological industries. 3. Food for fish and pets. 4. Protein flour, canned food. 5. Processing of manure and waste. 6. Study of regeneration processes

The work can be used for lessons and reports on the subject "Biology"

Ready-made presentations on biology contain various information about cells and the structure of the entire organism, about DNA and about the history of human evolution. In this section of our website you can download ready-made presentations for a biology lesson for grades 6,7,8,9,10,11. Biology presentations will be useful for both teachers and their students.

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Polychaete worms Polychaete worms or polychaetes are a class of annelids. Currently, this class includes more than 10 thousand species. Most representatives are inhabitants of sea waters. Length from 2 mm to 3 m. A distinctive feature is parapodia - lobe-shaped appendages extending from each segment of the body, bearing chitinous setae (chaetes).

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Systematic position and classification Annelids include from 7,000 to 16,500 species, divided in different classifications into a different number of classes. Traditional classification involves division into 3 classes: Polychaete worms Oligochaete worms Leeches

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Lifestyle They live all over the world, in the sea, in fresh water and on land. Marine forms are especially diverse, which are found at different depths down to extremes (up to 10-11 km) and in all latitudes of the World Ocean.

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Reproduction and development Annelids are dioecious; in some (earthworms, leeches) hermaphroditism has developed secondarily. Development in polychaete worms occurs with the larva - trochophore, in others - direct. Worms with a segmented coelom (that is, oligochaetes, polychaetes, but not leeches) are characterized by a high ability to regenerate.

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Nervous system The nervous system is composed of a large ganglion - the brain, from which the abdominal nerve chain departs. Each segment has its own nerve ganglion.

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Circulatory and respiratory systems The circulatory system is closed; it is based on the dorsal and abdominal vessels, connected by annular vessels that resemble arteries and veins. There is no heart; its role is played by sections of the spinal and circular vessels containing contractile elements. Respiration is cutaneous, in marine species - with the help of gills on parapodia.

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Digestive system Oral opening → pharynx → esophagus → crop → stomach → intestines → anus

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Digestive system The digestive tract is through. The intestine consists of three functionally different sections: the foregut, midgut and hindgut. Some species have salivary glands. The anterior and posterior sections are ectodermal, and the middle section of the digestive system is of endodermal origin.

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General structure Dimensions from 1 mm (Neotenotrocha) to 2 - 3 m (Eunice). The body is ring-shaped, with the number of segments from several to several hundred. The second, after segmentation, characteristic feature of annelids is the presence on their body of chitinous bristles growing from the cuticle. Each segment may have primitive limbs (parapodia) - lateral outgrowths equipped with bristles and sometimes gills. Locomotion is accomplished by contraction of muscles in some species and movements of parapodia in others.

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Characteristics Ringworms, ringworms, annelids (Annelida, from the Latin annelus - ring), the type of the most highly organized worms. Their whole is divided by partitions into segments, which correspond to the outer annulation; hence the name of the type - “ringed worms”. There are over 12 thousand species. There are 1180 species in Russia.

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Leeches Leeches (lat. Hirudinea) are a subclass of annelids from the class of belt worms (Clitellata). Most representatives live in fresh water bodies. There are about 500 species of leeches known in the world, and 62 species in Russia. Structure: the body length of different representatives varies from several millimeters to tens of centimeters. The anterior and posterior ends of the body of leeches bear suckers. At the bottom of the anterior there is an oral opening leading to the pharynx.

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Most oligochaete worms feed on plant detritus, which they absorb with the soil; several species are predators. Oligochaete worms are hermaphrodites. They reproduce through mating. The eggs are fertilized by one of the mating individuals and laid in a specific cocoon consisting of mucus secreted by glandular cells. Then, after development, a fully formed worm emerges from it. If the integrity of the worm's body is damaged, only one end, the anterior end, is subject to regeneration. The second end subsequently dies off. Nutrition and reproduction

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Oligochaete worms Oligochaeta are a subclass of annelids from the class Clitellata. Approximately 3,000 species have been described. There are 450 species in Russia. Most oligochaete worms live in the soil. Body structure Body length from fractions of a mm to 2.5 m (some tropical earthworms). There is a secondary body cavity - the coelom. Body segmentation is well defined inside and outside. Head and parapodia absent. Each body segment contains several pairs of setae. In most species, respiration is cutaneous; gills are not present. The circulatory system is closed.

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Nutrition and reproduction Among sessile polychaetes, sedimentators are the most common. They feed on detritus, extracting it from the water column with the help of hunting tentacles, which also serve as gills. Free-living polychaetes are detritivores or predators. Detritivores can extract organic matter from the soil by eating it. Most often, polychaete worms are dioecious animals. Polychaetes do not develop formed gonads. Germ cells develop from the coelomic epithelium, and after maturation they begin to float into the coelomal cavity. Fertilization is external. A larva emerges from the eggs - a trochophore. Some species are capable of reproducing asexually.

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Nutrition, movement and reproduction Leeches feed on the blood of vertebrates, mollusks, worms, etc.; there are also predator species that do not feed on blood, but swallow the prey whole (for example, mosquito larvae, earthworms). The method of movement of leeches is interesting. There are suction cups on both ends of the worm, which it can use to attach itself to underwater objects. The leech attaches itself to them with its front end, bends into an arc, and approaches. Leeches are hermaphrodites. Copulation involves two individuals that simultaneously release seed material.

summary of other presentations

“Diversity of annelids” - Class Oligochaetes. Leech class. Oligochaete worms Polychaete worms Leeches. Variety of annelids. Most often they live in stagnant fresh water bodies. Earthworms are well known and widespread. Inhabitants of the seas and oceans. Class Polychaete worms. Breeding period.

"Leeches" - Number and habitat. As a result, blood microcirculation improves, the likelihood of thrombosis decreases, and swelling subsides. Leeches are hermaphrodites. Hirudotherapy. Before laying eggs, a specialized part of the worm's integument is the girdle. History of medical use. Most representatives live in fresh water bodies. Some species have mastered terrestrial and marine biotopes. Medical leech - found in the north of Russia, in the Caucasus and Transcaucasia, in Poti, Lenkoran.

“Structure of annelids” - Body cavity of annelids. Environmental groups. Skin-muscle bag. Type Annelids. Annelids. Class Polychaetes. The cycle of substances in nature. Types of earthworms. General characteristics. Medical leech. Serpula. Variety of polychaete worms. Earthworms live in soil rich in humus. The role of earthworms in nature. The role of earthworms in human life. Class Oligochaetes.

“Features of annelids” - The shortest of all annelids. Answer the questions. Type annelids. The largest earthworm. Nervous system. Body cavity of annelids. Annelids. Digestive system. General characteristics of worms. The earthworm has a secondary cavity. The structure of the earthworm's organ systems. The role of earthworms in nature. Excretory system. Classification of earthworm.

“General characteristics of annelids” - New concepts. Features of life. Work in groups. Oligochaete worms. There is a secondary body cavity. Nereis. Aphrodite. General characteristics of polychaetes. Comparison of classes of rings. Leeches. Serpula. Classification. Internal structure of annelids. Features of the structure. Variety of annelids. Tiny polychaetes. Mating season. General characteristics of the leech class. The most majestic and graceful.

“Structure of an earthworm” - Annelids. Digestive system. Run your finger along the abdominal side. Let the worm crawl along a piece of paper. Consider a live earthworm. Nervous system. External structure of an earthworm. Draw an earthworm. Circulatory system. Mouth opening. Actions of various stimuli. Variety of annelids. Excretory system.

Subject:

"Pylum Annelids".

• Giant earthworms. They live only in Australia, and only in one region of this country - in South-Eastern Victoria. Giant worms were discovered and described in the distant past 1878 researcher and biologist Frederick McCoy.
• It’s hard to imagine, but this giant of the world of worms can reach 1.5-3 meters in length, 2-4 cm in girth and weigh about 700 grams. From a distance, such a worm can easily be mistaken for a long and thin snake; only when you get closer, the characteristic ring-segments inherent in all earthworms become noticeable. The number of the latter reaches 300 pieces.

Three-layer, bilaterally symmetrical; the skin-muscular sac is formed by longitudinal, transverse, oblique muscles, limits the secondary body cavity (in general), filled with liquid; each segment has outgrowths - parapodia.

Aphrodite (sea mouse)

Body cavity of annelids

in general

• Annelids have systems: muscular, open digestive, nervous (there are sense organs - vision, touch, taste, smell, hearing, balance), closed circulatory system, excretory, sexual (dioecious and fake hermaphrodites )
• Predators, saprotrophs
• Move due to parapodia and muscle contraction

• Complex structure determines complex behavior and lifestyle

TYPE RINGED WORMS

class polychaete

LEECH class

(polychotes)

• Nereid
• Aphrodite
• Peskozhil
• serpula

Class

Olychaetes

(oligohunts)

• Earthworm
• tubifex

• About 7000 species of polychaete worms. Most of them live in the seas, a few live in fresh waters, in the litter of tropical forests. In the seas they live on the bottom, where they crawl among stones, corals, and burrow into silt. Among them there are sessile forms and free-living ones. Mobile worms are mainly predators.

• Like all annelids, the body of Polychaetes consists of segments, the number of which in different species varies from 5 before 800.
• Polychaete worms have a head section and an anal lobe.
• On the sides of each body segment there are noticeable skin-muscular outgrowths - organs of movement, which are called parapodia. The worm is raking in parapodia from front to back, clinging to the unevenness of the substrate, and thus crawls forward.

nereid

Sea mouse (Aphrodite)

Nereis

Sessile form of sea worm

But there are also deep-sea ones.

Giant rift worms.

They live in huge colonies around underwater thermal wells.

These worms do not have a digestive system - they are provided with food by colonies of bacteria living in them, and the worms themselves deliver oxygen and sulfur-rich compounds to the bacteria.

head

segments

parapodia

eyes

mustache

tentacles

palpi

jaws

• Skin-muscle bag consists of thin cuticles , skin epithelium And muscles. Located under the skin epithelium two layers of muscles: transverse (circular) and longitudinal. Under the muscle layer there is a single-layer internal epithelium, which lines the secondary body cavity from the inside and forms partitions between the segments.

Digestive system

• The digestive system begins mouth, which is located on the ventral side of the head lobe, continues with the muscular throat(many predatory worms have chitinous teeth in it, which serve to capture prey).

• The throat follows esophagus And stomach .

• The intestine consists of three sections: foregut, midgut and hindgut. Anal hole located on the anal blade.
• Free-living polychaete worms are mainly predators, feeding on crustaceans, mollusks, coelenterates and worms. Sessile fish feed on small organic particles and plankton suspended in water.

• In polychaete worms, gas exchange (oxygen absorption and carbon dioxide release) occurs either the entire surface of the body, or areas of parapodia into which blood vessels extend. In some sessile forms, the respiratory function is performed by the corolla of the tentacles on the head lobe.

• Circulatory system in annelids closed: in any part of the worm's body blood flows only through vessels .
• There are two main vessels - dorsal And abdominal(one vessel passes above the intestine, the other below it), which are interconnected by numerous semi-circular vessels. No heart , and the movement of blood is ensured by contractions of the walls of the spinal vessel, in which blood flows from back to front, in the abdominal - from front to back.

excretory system

• The excretory system is represented by paired tubes located in each segment of the body.
• Each tube begins with a wide funnel facing the body cavity. The edges of the funnel are lined with flickering cilia. The opposite end of the tube opens outward on the side of the body. With the help of a system of excretory tubules, waste products that accumulate in the coelomic fluid are removed to the outside.

• The nervous system consists of paired suprapharyngeal nodes (ganglia), connected by cords into a peripharyngeal ring, a paired abdominal nerve cord and nerves extending from them.
• Sense organs are most developed in free-living polychaete worms. On the head of these worms there are a pair of palps, a pair of tentacles and antennae. These are the organs of touch and chemical sense. Many of them have eyes. There are organs of balance.

• Most polychaete worms dioecious. Gonads are present in almost every segment. Mature germ cells (in females - eggs, in males - sperm) enter first as a whole, and then through the tubules of the excretory system into the water.
• External fertilization. The egg develops into a larva that swims using cilia. Then it settles to the bottom and turns into an adult worm.

• Nereid larva and its transformation into a worm

• Some species reproduce and asexually. In some species, the worm is divided crosswise, and each half restores the missing part. In others, the daughter individuals do not diverge, and as a result a chain is formed that includes up to 30 individuals, but then it falls apart.

Development

• Polychaete worms occur with alternating life forms. Their larvae not alike on adults.
• Some Polychaete worms show care for their offspring (for example, they guard laid eggs).

Larvae of polychaete worms (trochopores)

• The importance of polychaete worms in nature is quite great: they filter water, purifying it; They are the orderlies of reservoirs, destroying a lot of decaying residues. Polychaete annelids are eaten by crustaceans, fish, echinoderms, and coelenterates.

Earthworm Letter

Hello!

I would really like to say: “Hello, dear friends!”, but I’m afraid you won’t like it: after all, not everyone wants to be friends with an ordinary underground worm! And I really want to find friends. I dare to assure you: we earthworms deserve, if not love, then deep respect for our tireless work. We help you people grow crops, loosen the soil, eat old leaves. Some say they don't like our appearance: "Slippery like a worm"; "Writtles like a worm." What's wrong with that? We are slippery and long because it helps us crawl underground. We can't fly! If we didn't squirm, we wouldn't be able to crawl. Dear children! If you want to be friends with me, then I will come to visit you.

« Sincerely, the underground dweller is an earthworm.

It is highly doubtful that there are other animals

(except for earthworms), which in the history of the earth

the barks would occupy such a prominent place.”

Charles Darwin

What do you think the scientist meant?

Class Oligochaetes (Oligochetes) (oligohunts)

Class POLOCHETATES TYPE Annelids SUBTYPE Belt CLASS Oligochaetes SQUAD

Higher Ligochaetes FAMILY Lumbricidae Earthworm

• VIEW
• From the polychaete worms the oligochaete worms evolved.

The Class Oligochaete worms include 4-5 thousand species.

The most common types of earthworms are: 1. Earthworm tetrahedral

(Eiseniella tetraedra) 2. Earthworm is smelly

(Eisenia foetida) 3. Earthworm yellowish-green

(Allophora chlorotica) 4. Earthworm is reddish

(Lumbricus rubellus) 5. Terrestrial or common earthworm

• (creep) (Lumbricus terrestris) The length of their body ranges from 0.5 mm to 3 m. The number of segments in different types of oligochaete worms ranges from 5-7 to 600. All segments their bodies the same . In sexually mature individuals, a thickening appears in the anterior third of the body - .

• glandular girdle They do not have parapodia or antennae, and each segment has four pairs of bristles - two pairs of dorsal and two pairs of ventral. The setae are the remains of the supporting elements of the disappeared parapodia that their ancestors had. The small number of bristles on the body of these worms gave the name to the whole class -
• Oligochaetes.

• The bristles are so small that they can only be detected by touch by running your finger from the back of the worm's body to the front (the figure shows the abdominal setae at 100 (1) and 300 (2) times magnification).
• The glandular cells of the worm's skin epithelium secrete mucus, which protects the skin from drying out and helps it move through the soil.

• The skin and the muscle layer, in close contact with each other, form skin-muscle sac. Between it and the internal organs there is a fluid-filled secondary body cavity (coelom) .
• Directly under the skin are circular muscles, and deeper – more powerful longitudinal .

• When the circular muscles contract, the body of the worm elongates in length.
• Contraction of the longitudinal muscles shortens the body. The alternation of such contractions ensures the advancement of the worm in the soil.

Digestive system

• The digestive system includes mouth, pharynx, esophagus, mid and hind intestines, anus .

Moving through the soil, the earthworm swallows its particles, passing them through the intestines, as if eating its way, and at the same time assimilating the nutritional particles contained in it.

Ducts empty into the esophagus calcareous glands, substances secreted by these glands neutralize soil acids.

Selection

Isolation - segmental nephridia (metanephridia).

• Gas exchange in oligochaete worms occurs the entire surface of the body. After heavy rain, when water floods the worm holes and air access to the soil is difficult, earthworms crawl out to the soil surface.

• The circulatory system of earthworms is distinguished by the fact that it contains muscular ring vessels capable of contraction - "hearts" located in 7-13 segments.

• The nervous system consists of peripharyngeal nerve ring and ventral nerve cord .
• Each segment has a nerve ganglion with nerves extending from it.

Due to the underground way of life, the sense organs of oligochaete worms are developed. weak. The organs of touch are sensory cells located in the skin. There are also cells that perceive light.

• Unlike Polychaete worms, Oligochaetes are hermaphrodites .
• Their reproductive system is located in several segments of the anterior part of the body. The testes lie in front of the ovaries.
• Sexual reproduction occurs with the participation of two individuals. When they come into contact, they exchange germ cells (the sperm of each of the two worms is transferred to special cavities - the seminal receptacles of the other).
• There is a clearly visible swelling on the front of the worm's body - belt .

• The glandular cells of the girdle secrete mucus, which, when dried, forms a muff. Eggs are first laid in it, and then sperm come from the seminal receptacles.
• Fertilization of eggs occurs in the coupling. After fertilization, the sleeve slides off the body of the worm, becomes compacted and turns into an egg cocoon, in which the eggs develop. Once development is complete, small worms emerge from the eggs.

• The earthworm has a well-developed ability to restore lost or damaged body parts - regeneration .
• If the worm's body is divided in two, then both parts will be able to exist independently, and the lost organs will be restored after some time.

Role in nature and human life

Types of annelids listed in the Red Book Russian Federation

• It's hopelessly difficult Life of a simple worm: Straighten up – The bird will peck Looking from afar. The worm listens sensitively - Where the shovel is there is a knock and a clink; Thoughts are the same: Suddenly it will cut Half for nothing! Collected by fisherman Chervyakov without further ado: Once the bait - Not fake It must be a significant catch. In the rain - with jets of water Floods all the passages It's a pity that the holes Without constipation - How far is it from trouble? In heavy rain - barely alive, Poking my head into the ground, Through the streams Crooked An earthworm weaves its way.

Eizenia salairica

• has about 400 species. Leeches are descended from oligochaete annelids. The body length of leeches is from several millimeters up to 15 cm.
• Representatives of this class are characterized by the following characteristics: constant number of body segments (33), presence of suction cups , absence of bristles on the body.

• The body of the leech is flattened in the dorsal-abdominal direction, with two suckers - perioral and posterior. There is a mouth in the center of the front sucker, and the back one serves only for attachment.

Externally, leeches are similar to other annelids, but they do not have bristles. The method of movement of leeches is connected with this: they move by alternately attaching suction cups to different objects and bending in a loop; many leeches are capable of swimming.

• Leeches lack parapodia, setae, tentacles and gills. On the anterior segments of animals there are from one to five pairs of eyes.
• Under the epithelium of leeches there are circular and very strong longitudinal muscles.

• Blood-sucking leeches in the oral cavity have sharp chitinous teeth. The salivary glands of leeches secrete a special substance - hirudin, which prevents blood clotting both in the wound on the victim’s body and in the stomach of the leech itself (therefore, wounds caused by leeches bleed for a long time).

• The stomach has so-called pockets for storing sucked blood. Therefore, the time intervals between meals for leeches can be very long - up to several weeks.

• Breathing is carried out through the entire surface of the body.

Nervous system and sensory organs

Leeches have a better developed nervous system than other worms. The sense organs perceive light, chemical, mechanical and other stimuli.

• Leeches - hermaphrodites. After mating, they lay numerous cocoons containing varying numbers of eggs.

Homework

§ 17 -18, workbook § 17 -18 and summarize.

Messages:

1) Gastropods.

2) Interesting facts from the life of gastropods.

3) Class bivalve molluscs.

4) Interesting facts from the life of bivalve mollusks.

• Earthworms live in soil rich in humus.
• Earthworms are hermaphrodites.
• The anal opening of the earthworm is located on the 16th segment.
• The skin is covered with a cuticle, and each segment has 16 bristles.
• Earthworms are predators.
• The skin of an earthworm has many mucous and poisonous glands.
• The phylum of Annelids is divided into classes: Oligochaetes, Polychaetes.
• Among the various worms, Annelids are the most progressive group.
• The musculature of an earthworm is formed by longitudinal and circular muscles.
• Oligochaetes play an important role in soil formation, decomposing organic residues.

Choose the correct ones from the proposed judgments

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Slide captions:

Presentation for a biology lesson in 7th grade on the topic “Type Annelids. class oligochaete worms" (Umk Pasechnika) Completed by a biology teacher at MBOU secondary school No. 120, Moskovsky district, Kazan Part 1 2015

There is no doubt that there are hardly any other animals that would have played such an important role in the history of the world as these lowly organized creatures. Darwin Ch., (1881)

Are earthworms really low-order creatures?

Purpose of the lesson: To study the features of the external and internal organization of the earthworm, as a representative of the class of oligochaetes, such as annelids, their role in nature and human life.

Classes of annelids

The most common types of earthworms are: 1. Tetrahedra earthworm (Eiseniella tetraedra) 2. Foul-smelling earthworm (Eisenia foetida) 3. Yellowish-green earthworm (Allophora chlorotica) 4. Reddish earthworm (Lumbricus rubellus) 5. Earthworm terrestrial or common (crawl) (Lumbricus terrestris)

Laboratory work “External structure of an earthworm”

setae External structure 120-150 segments

Warm up for the eyes Warm up for the eyes

Preview:

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Slide captions:

Presentation for a biology lesson in 7th grade on the topic “Type Annelids. class oligochaete worms" (Umk Pasechnika) Completed by a biology teacher at MBOU Secondary School No. 120 of the Moskovsky district of Kazan Part 2 2015

Organ systems (independent work with the textbook)

Ectoderm Mesoderm Endoderm Coelom Secondary body cavity

cuticle skin epithelium longitudinal muscles circular muscles Muscular sac

Digestive system Anus

“Hearts” abdominal vessel dorsal vessel annular vessels Circulatory system Why, although the earthworm does not have a heart, the textbooks contain the expression: “... through a closed circulatory system, blood moves thanks to the contractions of the “hearts” ...”?

Excretory system Excretory funnels - metanephridia

Nervous system Periopharyngeal nerve ring Ventral nerve cord Suprapharyngeal ganglion Subpharyngeal ganglion

Reproductive system Testes (♂) Ovaries (♀) Both hermaphrodites and dioecious are found Girdle

Sexual reproduction

Adult worm and development of young worms in a cocoon

The role of earthworms in nature: The cycle of substances in nature They form humus - humus (an organic part of the soil rich in nutrients) - “bread” for plants (98% soil nitrogen, 60% phosphorus, 80% potassium and other mineral elements for plant growth ) Link in the food chain Form soil drainage Disinfect the soil Loosen the soil Create soil ventilation Prepare the soil for plant growth

The role of earthworms in human life: 1. Humus (organic) fertilizer. 2. BAS (biologically active substances - essential amino acids, enzymes, vitamins) are used in: veterinary medicine, pharmacology, cosmetology, agriculture, biotechnological industries. 3. Food for fish and pets. 4. Protein flour, canned food. 5. Processing of manure and waste. 6. Study of regeneration processes

Wormworm Vermiculture

Vermifarm

Conclusions The body is divided into segments. Most have body outgrowths - bristles. They have a primary and secondary body cavity. The skin-muscle sac consists of skin, circular and longitudinal muscles. The nervous system consists of the peripharyngeal ring and the ventral nerve cord. The circulatory system is closed and consists of vessels. Breathing is carried out over the entire surface of the body. The digestive system is continuous. The excretory system is represented by metanephridia.

Rate your work in the lesson: “5” - learned the theoretical material, completed everything in the laboratory work, worked throughout the lesson; “4” - had difficulty studying theoretical material or performing laboratory work, but worked actively throughout the lesson; “3” - there were difficulties in completing all the tasks; by the end of the lesson I still didn’t understand anything. Need individual help

Homework Paragraph 9 Assignment in workbooks 1-3 on p. 16 to prepare a report about sea worms or leeches (optional). http://www.youtube.com/watch?v=TB94dkCgu_U http://www.youtube.com/watch?v=zlcvyNcs3Cw http://www.youtube.com/watch?v=-WpqyI-u1Gw