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summary of other presentations“Coelenterate organisms” - General features of coelenterates. Coelenterates are multicellular animals with radial symmetry. Subkingdom multicellular animals. Type coelenterates.
“Coral polyps” - The base of the colony is embedded in the ground. Massive or creeping colonies with a solid calcareous skeleton. The name Anthozoa means "flower-animals". Tree-like and whip-like colonies. The same number of radial partitions divides the chambers and the intestinal cavity. Order of sea anemone (Actiniaria). Order Madreporia corals (Madreporaria or Scleractinia). The species are colonial or solitary forms.
"Structure of Hydra" - Sexual reproduction. Attached lifestyle. Habitat and external structure. Biological experience. Nervous system. The cells are arranged in 2 layers. Cellular structure. How many planes of symmetry can be drawn through the body of the hydra. The vessel in which the hydra lives. Body symmetry. Classification. Why is hydra a multicellular animal? Leads an attached lifestyle. The structure and vital functions of coelenterates.
“Coral Reefs” - Many kilometers of beauty. Six-rayed corals. Asexual reproduction. Much darker, deeper water can be clearly distinguished. Atolls. Coral reefs. Relief-forming role. The barrier reef is usually divided into three parts. Taxonomy. Coral polyps. Biologically active substances. Feature polyps. Great Barrier Reef. Corals and medicine. Shape and color of coral. Multi-rayed starfish.
"Hydra" - Budding of a hydra. In the spring, a new generation develops from overwintered eggs. In late autumn, the hydras die. Hydras reproduce both asexually and sexually. Freshwater hydra. Topic: Diversity of coelenterates. The similarity in the structure and life processes of hydra with unicellular animals indicates the relationship between coelenterates and protozoa. Most representatives reproduce sexually and have planktonic or crawling larvae.
“Characteristics of coelenterates” - Multicellular animals. Terms. Trematodes. Fish. Layers of the body. The wind blows across the sea. Burn oral cavity. Meaning of Coelenterates. Class Scyphoid. General characteristics type. Hydroid class. Type of lower multicellular animals. Crossword. The only book. Type Coelenterates. Class Coral polyps. Knowledge and skills of students. Marine Coelenterates. Types of Hydra cells.
- The Great Barrier Reef is the world's largest complex of coral reefs and islands.
- The Great Barrier Reef stretches along the east coast of Australia for more than 2,000 km.
- His total area- 348,698 sq. km, more than the area of Great Britain.
- Depths no more than 50 m
- clear water
- Normal salinity
- Temperature not lower than 20 degrees Celsius
- 400 species of hard and soft corals: mushroom corals, brain corals and staghorn corals in all shades from red and yellow to black
- more than 4,000 species of mollusks, from chitons and gastropods to giant bivalves and octopuses, as well as countless sponges, sea anemones, worms, crustaceans and echinoderms
- home to more than 1,500 species of fish
- Several species of whales: minke whale, killer whale and humpback whale. These waters are the breeding territory of the humpback whale
- It is home to six of the world's seven species of sea turtles
- Mysterious dugong
- More than 240 species nest on the coral islands: petrels, phaetons, frigatebirds, six species of terns, including roseate terns, fulmars, grey-bellied sea eagle and osprey.
- TRIDAKNA GIANT (Tridacna gigas) - “king-shell”. Reaches a length of almost 1.5 m and a weight of 250 kg; Moreover, the actual body mass of such giants does not exceed 30 kg, the rest being the shell. Age, according to various estimates, is 100, 200 and even 300 years. The Great Barrier Reef off the coast of Eastern Australia is the real kingdom of tridacnids.
- Tridacna's feeding method is a filter feeder; it also feeds on its own zooxanthellae, which it “breeds” in the sunlit tissues of the edge of the mantle. A person wandering around the reef can not only injure himself on the sharp edges of the shell of a giant tridacna submerged in the ground, but also find himself trapped with his foot caught between the valves.
Coral reefs Some of the oldest ecosystems on the planet (primitive coral reefs existed as early as 500 million years ago; many of the groups of living organisms living on reefs are found in fossils dating back 50 million years; some date entirely back to the Carboniferous period - 100 million years) Widely distributed in shallow waters of warm seas. They are one of the most productive and taxonomically diverse communities
"Riff" or "Reef" - a word of Dutch origin, refers to a transverse row of strings passed through the sail (to reduce the sail area). from the German “Ripple” - rib - sharp underwater or surface elevations of the bottom in the shallow waters of the oceans, formed as a result of the destruction of the rocky bottom and shores or being the construction of colonial polyps.
All three types have a similar geomorphological profile. Reefs are formed at shallow depths. In transparent, running water On an initially rocky substrate At a water temperature not lower than +21 C In general, reefs are distributed between degrees north and south latitude
Corals are animals of the Coelenterata type. However, a coral reef is not a heterotrophic community, but a full-fledged ecosystem with a large mass of plants. Algae have a huge (determining) role in the functioning of the reef, i.e. a reef is a coral-algae system
Zooxanthellae and skeletal algae quickly and continuously remove carbon dioxide from coral tissues and contribute to the formation of insoluble calcium carbonate (CaCO 3) - the main material of the reef frame. The rate of skeleton formation of reef-forming corals is 10 times faster than that of non-reef-forming corals, but simply those living on the reef. The dependence of corals on endozoic and skeleton-forming algae determines their requirements for the amount of incoming light. Reef growth is limited maximum depth meters (average depth - 40 meters) depending on the transparency of the water. Temperature (not lower than 21 degrees) limits physiological process formation of calcium carbonate.
Nutrients, once absorbed by reef corals, can be repeatedly circulated between the coral and the algae. Therefore, the loss of nutrients by the reef occurs very slowly. Symbiont algae significantly increase the coral’s ability to build a skeleton. The rate of calcification by the reef is approximately 10 times higher in the light (i.e., when the algae are “working”) than in the dark
The coral reef community includes: six -beam corals (Hexacorallia) - eight -beam corals (Octocarallia) - Gorgonaria, altacia, hydroeine polyps - red cortical algae - Corallines Green Lime (the most common Rifs gender of Halimeda) green threaded and plastered water grew (ulva , Cladophora) Diatoms Blue-green algae Brown algae (Sargassum, Dyctiota, Cystoseira) Sea grasses (genus Halophila, Thalassia)
The Great Australian Barrier Reef was discovered back in 1768 by James Cook. It stretches for more than 2000 km. It consists of approximately 3000 individual coral islets connected underwater, separated by narrow channels. The maximum width of the reef at Cape Manifold reaches 320 km.
Modern problems of coral reefs RegionShare of the total reef area, % Problems Southeast Asia30Most (60-70%) under the influence of fishing, the entry of pollutants Pacific Ocean25Up to 30% under the influence of fishing, the introduction of predatory species. pollution Indian Ocean24About 20% influenced by pollution and fishing Caribbean9Coastal pollution, tourism, weakening of hydrodynamics Atlantic Ocean (except Caribbean)6Infrastructure development in coastal zone, tourism, pollution Central Asia6Shipping, oil spills, tourism
