Download presentation of bone cartilaginous fish. Presentation - Class Cartilaginous fishes: sharks and rays - Class Bony fishes: cartilaginous, cartilaginous, dioecious and ray-finned. IV. Consolidation of knowledge

CARILY FISH Veretennikova Svetlana Valerievna Biology teacher MBOU secondary school No. 19, Nizhny Novgorod

Cartilaginous fish are among the most ancient of fish. The first shark-like fish lived in the Devonian seas 410 million years BC. In the course of evolution, the rays became flat, their lateral fins turned into a kind of wings, and they descended into the bottom layers of the world's oceans. These marine animals became active predators and colonized all areas of the ocean with the exception of great depths. With a few exceptions, all cartilaginous fish live in salt water.

This terrible white predator is looking for food in the ocean. Sensitive nostrils on the snout: Blood can smell even a mile away. Near the victim circling nearby, And the circles are already, already. Turns up his nose ... Oh my God! The jaw looks like a trap! She closed her sharp teeth. This is how she hunts ... Svetlana Volosevich

There are no gill covers, and on each side there are 5 - 7 gill slits. There is no swim bladder. Sharks are armed with many sharp teeth with their mouths, have an elongated body with an unequal tail. There are about 370 shark species. Gill slits

Sharks are very widespread: they live in coastal and open waters, some in rivers (for example, in the Amazon, Ganges). Most sharks are viviparous, some lay eggs. Almost all sharks are predators. They feed on fish, benthic invertebrates, echinoderms, molluscs, and worms.

Most sharks - great white, blue, blacktip reef, hammerhead and others - swim day and night: firstly, they do not have a swim bladder, and if the shark stops, it will go to the bottom; secondly, sharks, excluding some species, do not have a mechanism for pumping water through the gills, from which the blood receives oxygen.

Sharks are the most mysterious and maligned creatures of the ocean. Over the several hundred million years of their existence, they have changed only slightly over the past ten million years. There are about 370 species of these fish, ranging from 15 cm of the carnivorous dwarf shark to 13 m of the planktivorous whale shark. Dwarf shark Whale shark

WHALE SHARK, which feeds on plankton and is common in the southern parts of the Atlantic, Pacific and Indian Oceans. The largest specimen, according to precise measurements carried out by scientists, was 12.65 m long, 7 m in girth of the thickest part of the body and a weight of 15-21 tons.

Giant shark

Tiger shark

The tiger shark is usually quite slow, but becomes quick and agile when it senses food. Migratory birds, cormorants, sea snakes, pieces of dolphins and crocodiles have also been found in the stomachs of tiger sharks. This shark, without undue disgust, refers to carrion and garbage. The list of edible and inedible items extracted from the stomachs of tiger sharks is very large and includes dogs, a cat, a cow's hoof, antlers, various rags, boots, bags of coal, cans, beer bottles, cigarette boxes, potatoes, leather wallet and many other things. In tropical waters, the tiger shark is perhaps the most dangerous species. There are many known cases when body parts of human victims were found in the stomachs of caught sharks. Some of these finds are probably due to the devouring of corpses, but many of the victims, undoubtedly, met the shark while still alive and well. Attacks were recorded in many areas - off the coast of Florida, the Caribbean, Senegal, Australia, etc. These attacks took place both off the coast and away from them. Thus, off the coast of New South Wales (Australia) in 1937, a tiger shark killed two young men swimming on the beach; in 1952, near a small island in the Puerto Rico region, a shark attacked an underwater hunter who harpooned a fish; in 1948 a boat was attacked heading for the coast of Florida. The list of documented tiger shark attacks on people and boats is quite impressive in recent years.

Shark white shark - nanny Shark - hammer Polar shark Herring shark

The stingrays are characterized by a very “flattened” body and large pectoral fins, fused with the head. The mouth, nostrils and five pairs of gills are on the flat and usually light underside. The tail is whip-shaped. Most stingrays live in seawater, but there are several freshwater species as well. The upper side of the stingrays is adapted in color to a particular living space and can vary from light sandy to black. On the upper side there are eyes and holes for water to enter for breathing. Most stingray species are benthic and feed on shells, crayfish and echinoderms. One of the most famous types of rays is the manta ray. Stingrays from the eagle family reach large sizes, whose wingspan can reach 2.5 meters, and the length - up to five meters; as well as stingrays from the stingray family, reaching 2.1 meters in width and up to 5.5 meters in length. A detachment of electric rays is endowed with a special "weapon", whose representatives, with the help of a special organ made of transformed muscles, can paralyze prey with electric discharges from 60 to 230 volts and over 30 amperes.

Manta Sea Fox Eagle Stingray Electric Ray

The body of the chimera tapers towards the posterior end and ends with a long (up to half the length of the body) whip-like tail. The length of adults from the front end to the tip of the tail varies from 0.6 to 1.5 meters. Large pterygoid pectoral fins give their characteristic appearance to chimeras. An open groove of the lateral line is located on the side of the head and body.

Perfectly streamlined body shape, fantastic sense of smell and razor-sharp teeth - all this makes the shark the most terrible sea predator. Sharks live on Earth 350 million. years and during this time has changed little. A shark must always be in motion - it breathes oxygen, which is taken by the gills from the oncoming stream of water. And besides, the shark does not have a swim bladder to keep it in the water. Unlike other fish, sharks and related stingrays have a cartilaginous skeleton rather than bone. Stingrays have a flat body, on the underside of which there is a mouth with flattened teeth: with them, the stingray gnaws the shells and shells of benthic animals. The stingrays gracefully swim at the bottom, flapping their huge fins-wings.

Sharks SHARK-mako. Mako body length can reach 3.5-4 m, and weight 450 kg. The back is dark blue, the belly is white. Sharp and thin teeth have smooth edges. Mako are common in tropical waters of the Atlantic, Pacific and Indian oceans. They are considered the fastest of all known shark species and are capable of jumping over the surface of the water. Mako feed on cephalopods and various, sometimes very large fish. In the stomachs of some large individuals, the remains of a swordfish are found. Mako is a real danger to swimmers and can also attack small boats. The commercial value of these sharks is not great, but they are an object of sport fishing.

Whale shark The largest living fish is the whale shark, reaching a length of 20 meters. This huge but harmless creature feeds, like whales, exclusively on zooplankton. Egg capsules of this shark reach almost 70cm in length and 40cm in diameter.

White shark The largest predatory fish is the white shark, or the man-eating shark. Its length can exceed 9m, and its weight is 2.7t. The white shark plows the ocean, swimming more than 480 km every day, and devours any living creature, often swallowing it whole. The great white shark sometimes attacks people.

The shark is mainly driven by its tail. Oscillation of the upper tail lobe propels the shark forward, and the characteristic slope of the pectoral fins keeps it horizontal. A shark cannot instantly stop the movement of fins. To stop, she turns sharply.

Hammerhead Shark Among all the inhabitants of the sea that attack humans, the most terrible is the shark. Bloodthirsty, cunning and lightning fast, she instilled fear in people at all times. The hammerhead shark is one of the largest sea creatures. Its average size is 4-5 meters, but you can also find those whose size exceeded 7 meters. The world's largest hammerhead fish, 7 meters 89 centimeters long and weighing 363 kilograms, was caught off the coast of New Zealand.

Tiger shark Deep in the wilds of the sea, whose outfit is very unremarkable, awaits a new victim. It could be a turtle, a gawking sea gull, or even a human. Unlike other sharks, the voracious tiger shark with huge jaws will try to eat whatever it gets in its way. Even a wooden boat or iron sheets will have a snack. Unpretentious tiger-like stripes provide the shark with the camouflage that gives it its name. The more we learn about this bloodthirsty shark, the more formidable features it acquires in our eyes.

Nurse Shark Nurse Shark, a cartilaginous fish of the carpet shark family. Body length from 2.5 to 4 m, weight kg. The color is monochromatic, yellowish-brown, small dark spots are scattered over the body of young individuals. It lives in the Atlantic Ocean off the coast of America from Florida to Brazil, off the coast of West Africa, and also in the eastern part of the Pacific Ocean. Usually it keeps in flocks of up to 40 individuals near the shore, at a depth of up to 3 m. These slow and inactive sharks feed on octopuses, crabs, shrimps, sea urchins, and also small fish. For humans, as a rule, it is not dangerous. However, there are known cases of provoked attacks on swimmers. At the same time, it holds a person's hand or leg with a death grip and does not open its jaws even after being removed from the water.

Katran sharks Katran, or common spiny shark, is one of the most widespread sharks in temperate latitudes. Following the movement of food fish, it makes long-distance migrations along the Atlantic coast of the United States and in the eastern part of the Sea of \u200b\u200bJapan. In Russia, it is found in the Black, White, Barents and Far Eastern seas. Length 2 m, weight 15 kg. It leads a near-bottom schooling lifestyle, rises to the water surface at night. It feeds on fish, squid. Katran does not attack a person, but its spines in front of the dorsal fins are weakly poisonous, and an accidental injection by them is very painful. In some places it reaches a high number and seriously harms the fishery, tearing tackle and eating fish in nets. At the same time, he himself is a commercial fish, the world catch is about 30 thousand tons per year. The special value of katran is that its meat does not have an unpleasant odor characteristic of many sharks.

Sea fox The length of this shark is up to 6m. She lives mainly in the warm coastal waters of the Atlantic and Pacific oceans, but sometimes swims further north in summer. The sea fox swims in a circle, driving off a school of fish with its tail. Then, with her mouth wide open, she pounces on them and devours them.

Reef sharks An adult of this family is about meters long. The body of the gray reef shark is shaped like a torpedo, which allows it to be very fast and make rapid maneuvers. As for the appearance of the shark, it usually has a gray color of various shades with a black stripe on the tail. The main victims of these predators are reef fish. However, in addition to them, it also feeds on crayfish and cuttlefish. This type of shark prefers to feed in a short distance from land. The gray reef shark often attacks humans. For many, it causes fear. This sharkakul becomes enraged by a small drop of blood in the water or vibrations, it begins to aggressively try to bite the victim, even if it is not nearby.

Bull Shark Bull shark often enters freshwater sharks, upstream of large rivers. She is very dangerous to humans, especially when meeting her in a confined space. This shark-shark is medium in size but aggressive, unpredictable and fast in movement. These sharks have a rounded muzzle, as well as eye bumps, from which it gets its name. Bull sharks share common anal fins as well as two fins located on the back. It is worth noting that they are covered with thorns. Among other things, they have 5 gill openings. By themselves, these sharks are small in size. The largest species among these sharks is the Port Jackson bull shark. Shark It measures about 1.65 meters in length. These sharks prefer to live in warm temperate regions, as well as in the tropics. The main zones of their distribution are the Indian Ocean, the eastern part of the Pacific Ocean.

Bigmouth Shark Since its discovery in 1976, this deep sea shark has remained the only species in the bigmouth shark family. Until November 2004, fewer than 25 specimens were observed, of which only a few were scientifically researched. Little is known about the shark's anatomy, behavior, and range, with the largest measured specimen being a dead female, 5.63 m in size, washed ashore on April 19, 2004, near the town of Ichihara in Tokyo Bay. The smallest specimen was a male caught on March 13, 2004 near the island of Sumatra, which measured 1.77 m. The most noticeable external feature to which the largemouth shark owes its name is a relatively large rounded head with a short nose and huge mouth. Its back is dark brown; sharks have two dorsal fins, one asymmetrical caudal fin, two large pectoral fins and two fins on the abdomen, of which the rear pair is much smaller.

Stingrays Sharp-tailed Skates family of cartilaginous fishes of the superorder stingrays, includes two genera. In terms of body shape, representatives of this family occupy an intermediate position between sharks and rays. They have a flattened body, the tail is almost not separated from the trunk. Along with an elongated snout, these rays are characterized by a two-lobed fin with pointed ends, reminiscent of the tail fin of sharks. Shark-tailed rays are common in tropical waters off the coast of Africa, Asia and Australia. One of the species, the shark-tailed ray, is of commercial importance. Its length is up to 3 m, weight is up to 225 kg. The main food is benthic invertebrates.

Sea Devil Sea Devil is the largest stingray. Unlike most stingrays, the devil swims in the water column, smoothly flapping his pectoral fins, reminiscent of the wings of a huge bird. The span of these "wings" can reach almost 7 meters. The sea devil gets its name from its horn-like head fins. With these fins, the stingray drives water saturated with zooplankton and small fish into its mouth.

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Lesson type: formation and consolidation of new knowledge.

Goal:familiarization with the general characteristics of the class, the diversity and features of the structure and behavior of orders of sharks, rays, chimera.

Tasks:

to master the main features of cartilaginous fish;
understand the classification;
to reveal the traits of adaptation to the environment;
find out the meaning in nature and in human life;
be able to recognize representatives of the Sharks, Stingrays and Chimera-like squads;
develop the ability to observe animals while watching a video clip;

Teaching methods:

By the source of transmission and perception of educational information:

verbal (story, conversation);
visual (illustration, demonstration);
practical (test, exercises).

By the degree of management of educational work:

educational work under the guidance of a teacher;
independent work of students;
work with the textbook;
practical control and self-control.

Form of organization of educational activities of students:

frontal
individual
steam room

Equipment:

illustrations depicting representatives of the type,
a computer,
screen,
multimedia installation,
power Point presentation.

During the classes

I. Organizational moment.

- Let's summarize. Slide 5

- Origin. Slide 6

Related to ancient shell fish
In primitive antiarchs, the whole body was chained in a shell of skin plates;
In carnivorous arthrodirs, the carapace covered only the front part of the body.
Armored - the first jawed fish; their jaws arose from the gill arches, shifted closer to the mouth, and consisted of pointed bony plates.
The shellfish became extinct in the late Devonian.

2. Characteristics of the units.

Sharks. general characteristics slides 7-8

Shark variety. Slide 9-13, film slides 10, slide 12

Gymnastics for the eyes slide 14

Blink quickly, turn off the gas and sit quietly, slowly counting to 5 (4-5 times)
Close your eyes tightly (count to 3) Open and look into the distance (count to 5) (4-5 times)
Make 3-4 circular movements with your eyes to the right side, then to the left. Look into the distance at the expense of 1-6. (1-2 times)

Stingrays (Explanation of the teacher with elements of conversation.) slides 15-17

Take a look at the picture. What traits of adaptability to the environment have you seen?

Chimera(Explanation of the teacher with elements of conversation.) slides 18-19

Additional material for the teacher (See. appendix 8)

IV. Consolidation of knowledge

slide 20

Working in pairs (check with each other)

Answer on the board

slide21

To which order do these fish belong?

Presentation to the lesson on the topic "Cartilaginous fish". It was held in the 7th grade. Each slide reflects the highlights of a new topic. Most of the representatives of the cartilaginous children liked the angler fish))))))))).