Marine protozoa Marine protozoa refer to tiny single-celled marine animals (including groups formed by single cells). Protozoa are the most primitive and lowest animals in the animal kingdom. The smallest individual is about 1 micron, and the largest is a few centimeters, which are generally very small and can only be seen with the help of a microscope. There are usually nuclei and food vacuoles in the protoplasm of single-celled individuals, and some species have cilia or flagella. The word "protozoa" is a combination of Protos (meaning primitive) and zood (referring to animals). It was first proposed by G.A. Goel Derfuss in 18 17, and first defined by German C.T.E.von Arbold in 1845.
Marine protozoa are widely distributed, from tropical equatorial waters to cold polar waters. Most protozoa belong to marine plankton, concentrated in the food-rich ocean surface to the water depth 100 meters; There are also many kinds of benthic organisms. Most of the marine protozoa live freely, and a few live parasitically, generally forming cysts in unfavorable environment.
The main groups of marine protozoa are foraminifera, radiolarians, dinoflagellates, tinnitus and siliceous flagellates.
Marine coelenterates Marine coelenterates are the beginning of metazoa and the backbone of animal evolution, while porous animals are just a side branch. There are about 10000 species of marine coelenterates, most of which live in the ocean, and there are few species in fresh water. The coelenterate's body is radially symmetrical, which is a progress in animal evolution. However, this symmetrical animal can only be divided into upper and lower parts, not front, back, left and right parts, so it is difficult to move quickly and directionally, and it can't crawl. Coelenterates live in a fixed or floating life. It has different shapes, but basically there are two shapes, namely, a column suitable for fixation, called hydra type; Umbrella suitable for floating is called jellyfish type, which is often two different stages in the life history of an animal. The hydra-type individuals produce jellyfish-type individuals through budding reproduction, and the jellyfish-type individuals produce hydra-type individuals through sexual reproduction, which is called generation alternation.
The coelenterate is composed of ectoderm and endoderm, with a layer of acellular gelatin in the middle of the ectoderm. The cavity surrounded by endoderm in which food is digested is called gastric circulation cavity. This cavity has a mouth without anus, and indigestible food residues are still discharged from the mouth. Coelenterates have differentiated into simple tissues, but not specialized into organs, ectoderm and endoderm form epithelium, cells have differentiated, and nerve tissue and muscle tissue are in the low stage of development. Nerve tissue is composed of nerve cells scattered at the base of ectoderm. These nerve cells have processes and form a neural network with each other. Some cells in endoderm and ectoderm differentiate at the base to form myofibrils, which are called dermatomyocytes. This is the original muscle tissue, which has not been separated from the epithelium. There are also some cells that can accept stimulation, which are sensory cells. Other cells can secrete digestive enzymes or mucus, which are called gland cells. The food ingested by coelenterates is first digested outside the cell, broken down into particles, and then swallowed by musculocutaneous cells for intracellular digestion and absorption of nutrients. There is also a kind of stinging cell with complex structure outside this cell, which has a small capsule with thin tubular stinging silk in it, called stinging silk sac. When stimulated, the barbed wire can be released and can secrete venom, paralyzing or poisoning the prey. Therefore, coelenterates are also called echinoderms. Vertebral cells are unique to coelenterates. There are two reproductive modes of coelenterates: asexual reproduction and sexual reproduction. Pudding is a common form of asexual reproduction, some of which can be divided vertically or horizontally; Sexual reproduction is the combination of sperm and egg. In the development process, it passes through the floating larva stage with cilia and can swim, and then develops into an adult.
Some coelenterates can secrete hard calcareous or horny bones. After the death of species with calcareous bones, the bones left behind can form islands in the ocean. Both Xisha Islands and Nansha Islands in China are composed of calcareous skeletons of coelenterates.
Coral has existed for centuries, and people always think that coral is a kind of marine plant. Because the beautiful coral reef really looks like a strange moving garden. Its color is bright and bright, and it looks like a bush. There are even black slugs and snails living on it. It was not until the middle of17th century that the French biologist Pei Sagnell dared to make his discovery that coral was actually a marine animal known to the world after 10 years of research. The book recording his findings was published in 1752.
Coral is a kind of invertebrate coelenterate, which is common in tropical and subtropical waters near land. The surface of the coral tree process is attached with continuous meat, which is covered with corals, called corals, and the bones are made of calcium or keratin. Coral is cylindrical and has eight or more tentacles. There is a mouth in the center of the tentacles, which is connected with the tubular esophagus in the lumen. Corals eat, breathe and excrete waste through these pipes. Corals, like jellyfish and anemones, prey through tentacles with stinging cells, and plankton and micro-organisms in the ocean become their food.
There are many kinds of corals, but the basic components of all coral reefs are reef-building corals or hard corals. Their bones are like a tiny cup, including esophagus and tentacles. When hydra died and was replaced by a new hydra, the bones left behind formed the coral reef today.
However, coral reefs are not only the product of animal metabolism. In fact, more than half of the hard coral body is composed of plant matter. Otherwise, hard corals cannot produce limestone or even survive. It is found that there is a very fine zooxanthellae in the tissue of every hard coral. These living dense zooxanthellae use solar energy for photosynthesis, converting seawater into oxygen and carbohydrates, while corals use these oxygen and carbohydrates released by zooxanthellae as food. In this chemical process, zooxanthellae actively guides corals to make limestone. Because of its attachment to coral, zooxanthellae not only obtains a stable and protected environment, but also consumes carbon dioxide and other wastes discharged by coral. Therefore, no one can live without coral and zooxanthellae. The relationship between them is the basis of all coral life.
Coral belongs to Polypodiaceae, a class of coelenterates. Coral is an amorphous group structure composed of coral polyps, which are fixed in a calcareous "body room" respectively. Coral is a life-long coral, only larvae can swim freely, and when they mature, they are fixed on the seabed. Hydra type is divided into base, body and terminal tentacles, and the base is generally slightly expanded into a circle; Most parts of the body are cylindrical, and the tentacles of the tentacle are its predatory organs, with stinging cells on them, which can pierce tiny animals, anesthetize or kill prey, and then swallow the prey into the intestines with the mouth of the tentacle.
Reef-building corals are typical tropical marine animals (there are 200 species in China), which can only live in seawater with water temperature above 18℃. Corals multiply by asexual and sexual reproduction. It is precisely because coral has been derived for hundreds of millions of years that the deep layer has died, the upper layer continues to grow, and calcium accumulates more and more. Together with other reef-building animals and plants, spectacular coral reefs and islands scattered in the global warm zone ocean have been formed through crustal changes. For example, the South China Sea Islands in China and Dammam Reef in Australia are all built by reef-building corals and other reef-building animals and plants.
Because of the colors of coral and zooxanthellae, the body and tentacles of coral in the ocean are colorful, including red, orange, red, green, blue and purple. However, coral skeletons that people usually see are coral skeletons formed by fresh water after coral death, such as antlers, willow corals shaped like branches, honeycomb corals shaped like honeycombs, brain corals shaped like the surface of the brain gyrus, and Shi Zhi corals shaped like mushrooms. They are as white as jade, and people can't put it down.
Special life needed by reef-building corals. Environment and conditions greatly limit the geographical distribution of coral reefs around the world. Although the ocean is vast, the waters suitable for reef-building corals are relatively limited. In the modern ocean, coral reefs are only distributed between 32 north latitude and 32 south latitude.
In the past, people often saw that corals were only used to burn lime and building materials; But now, corals can also be used as beautiful handicrafts. Red coral can be compared with gold, platinum, pearls and jadeite whether it is used as decoration or decoration, and its price is extremely expensive, so it is called "jewelry coral". The largest red coral in the world was collected from the seabed near Guishan Island in Yilan, northern Taiwan Province Province in 1980. This "Coral King" is pink with five main branches, with a height of 125 cm and a weight of 75 kg. It is displayed in a coral company in Linsen North Road, Taipei, with a value of $5 million and a "tree age" of 20,000 years. 1989 the commercial value of pink coral is more than 6000 dollars per kilogram.
Black coral is also a rare treasure with the same value as gold. Black coral necklaces, bracelets and earrings are made by cutting, grinding and polishing, which are black and shiny and expensive.
In addition, some scholars have extracted active substances from the organic tissues of soft corals and gorgonian corals, which can become new drugs for anticancer, antitumor and cardiovascular diseases.
Jellyfish Jellyfish is very rich in nutrition, not only rich in protein, fat and vitamins, but also rich in minerals. Both biochemical structure and human absorption are unique. Coastal fishermen often use it to treat diseases. Fishermen are prone to enteritis in midsummer, so it is good to eat some fresh jellyfish properly. Cut jellyfish into thin strips, soak them in sugar water to remove salt, add sesame seeds and coriander to taste, and eat a bowl in summer, and thirst and boredom will suddenly disappear.
There are many records about jellyfish in ancient books, and the more detailed one is Li Shizhen's Compendium of Materia Medica: jellyfish "the big one is like a bed, the small one is like a bucket, without eyes and stomach, with shrimp as its eyes and shrimp moving like a snake." On the surface, it looks like an umbrella, reddish in color, with a handle under the body plate, an opening at the lower end and many tentacles at the edge, just like a beautiful girl with blonde hair over her shoulders and a tulle skirt.
Sailing champion: Although the jellyfish has a huge disk, it is most suitable for driving wind or current. When there is a breeze, as long as it floats on the sea, it can swim on the sea as it pleases. When it wants to cross the ocean, it just needs to lean to one side. In the semi-submersible area, the turbulent current will take it to the ideal place. Jellyfish may not swim very fast, but it may win the gold medal in the long-distance race! There are thousands of creatures in the sea, but it is really strange that jellyfish can ride the wind and gallop north and south effortlessly.
"Hearing" is superior: jellyfish have no ears, but "hearing" is superior. Every time a ship passes through an area with dense jellyfish, it will be surrounded by a reddish jellyfish. Against the backdrop of the sea, people seem to be in a lotus pond, which is beautiful. As the Sun Festival approached, the "Lotus" on the water suddenly disappeared. When the ship was far away, the jellyfish rushed out of the water again. How do jellyfish "hear" sounds? People finally found that there are many reddish shrimps hidden in the folds of jellyfish head. These strange shrimps are as big as Starscream. Although they are small, they are very agile. These little guys were born with jellyfish, and the jellyfish became its host. Their relationship is very harmonious. Whenever jellyfish reach an ideal sea area, first let these shrimps have a full meal, and then start eating by themselves. Shrimp never forgets its master's preferential treatment and gives jellyfish a good "guard" with great vigilance. Once the situation is abnormal, they quickly get into the wrinkles on the jellyfish's head-this is equivalent to informing the jellyfish. Suddenly, the jellyfish quickly dived into the water.
Strange legend: jellyfish, called sea snake, ancient mirror and sea monk's hat in ancient times. Modern science classifies it as a large jellyfish among coelenterates. There is also an interesting legend about the sea monk jellyfish: the Zen master Fahai interfered with the marriage of Bai Niangniang and Xu Xian, resulting in flooding and untold suffering. The Jade Emperor was very angry. He wanted to arrest Zen master Fahai, but monk Fahai was hiding in Tibet, and there was nowhere to hide. Later, he found a safe place-crab shell. In the panic, the monk Fahai accidentally lost the monk's hat-this is a jellyfish floating in the water. On that day, the little girl of the Dragon King of the East China Sea fell in love with the mortal fish lang, and she secretly escaped from the Dragon Palace while the men in black were quiet under the moon. When the Dragon King learned that his beloved daughter had abandoned the palace, he quickly sent a team of soldiers and crabs to pursue him. Shrimp soldiers and crabs will get closer and closer. Dragon lady suddenly found something floating on the sea and used her quick wits to hide. In a rage, the Dragon King cast a spell and shouted "Ding". Since then, the dragon lady has never appeared under her hat again.
Today, people can still see a "girl" with fair and delicate face, blonde hair and silver hair when they uncover the umbrella-shaped body plate of jellyfish. Legend has it that the dragon girl was imprisoned after being framed by her father, and she felt that her father was cruel, so she tried her best to collect toxins from the sea, hoping to fight her father one day. This is also the reason why people accidentally get stung red and swollen when catching jellyfish.
Jellyfish jellyfish is a very beautiful aquatic animal. Although it has no spine, its body is very huge, and its huge body is mainly supported by the buoyancy of water.
Jellyfish is shaped like a transparent umbrella with different diameters. The umbrella of the big jellyfish can reach 2 meters in diameter. There are some whisker-like strips on the edge of the umbrella, which are called tentacles. Some tentacles can be as long as 20 to 30 meters, which is equivalent to the length of a big whale. Jellyfish floating in the water extend their long tentacles around. Some jellyfish have umbrellas with colorful patterns. These swimming jellyfish of different colors look very beautiful in the blue sea.
Jellyfish appeared before dinosaurs, dating back to 650 million years ago. At present, there are about 200 species of jellyfish found in the world, and there are about 8 common species in China, namely Haiyue jellyfish, Baixia jellyfish, jellyfish and crested jellyfish.
The tentacles of jellyfish are covered with stinging cells, like small beans on tentacles. This kind of stinging cell can shoot poisonous silk, and when it meets an "enemy" or prey, it will shoot poisonous silk to scare off or poison the "enemy". There is a small ball on the thin handle in the middle of the jellyfish tentacles, and there is a small "listening stone" in it, which is the "ear" of the jellyfish. Scientists simulated the sound wave transmission organs of jellyfish and found that the information of ocean storm 15 hours before its arrival could be detected.
Although jellyfish is very beautiful and comfortable in water, it can't live without water. The water content of jellyfish reaches 98%, and its eating, digestion and excretion must be completed in water. Without water, jellyfish's body will become smaller and uglier.
Jellyfish is more dangerous than cobra. A few years ago, the American World Wildlife magazine listed 10 species of the most poisonous animals in the world, and the box jellyfish living in the ocean topped the list. Box jellyfish, also known as sea wasps, belong to coelenterates and mainly live in the coastal waters of northeast Australia. Adult box jellyfish are football-sized, mushroom-shaped and almost transparent. An adult box jellyfish has billions of poison sacs and needles on its tentacles, enough to kill 20 people. The toxicity is obvious. Its venom mainly damages the heart. When the venom of box jellyfish invades the human heart, it will destroy the consistency of the beating rhythm of human cells, thus making the heart unable to supply blood normally and leading to rapid death.
The largest jellyfish is the arctic jellyfish distributed in the northwest Atlantic. 1870, an arctic jellyfish was washed into Massachusetts bay, USA. Its umbrella is 2.28 meters in diameter and its antenna is 36.5 meters long. The smallest jellyfish is only 12 mm long.
When the comb jellyfish swims in the sea, it emits blue light. When it glows, the comb jellyfish becomes a dazzling colorful ball. When it swims, the light band swings with the waves, which is very beautiful. At present, biologists in Singapore are conducting an experiment, trying to transplant the luminescent genes of jellyfish to other fish.
Powerful and deadly jellyfish also have natural enemies. There is a kind of tortoise that can shuttle from south to south in jellyfish, and its tentacles can be easily broken with its mouth, so that it can only roll up and down, and finally lose its resistance and become a delicious meal for turtles.
Anemone is a big ocean, which is amazing. Anemone can be regarded as a magical and charming marine life, and its elegant name is inevitably reminiscent of sunflowers in the sun. In fact, they look more like a blooming rose with a circle of tentacles scattered around at the top, just like the petals of a rose. No wonder people call them "undersea roses". When people reach out and touch them, they will quickly spit out a stream of clear water, take back the "petals" and shrink into a ball. It is not easy for you to pick these flowers. These colorful "flowers" and "flower debates" are also like stretched chrysanthemums, so they are also called "undersea chrysanthemums". From the outside, anemones are really gorgeous and moving, but in fact they are not as cute as their "looks". Its mouth is very big and its appetite is very good. It can swallow shrimp and small fish in one gulp. Anemone's body is as soft as jellyfish, and the tip of each tentacle has a poison sac with a sharp line in it. Once the prey is encountered, one of the lines will pierce the skin forward and the venom will flow out, so that the "opponent" will be quickly conquered. Because of this, other marine creatures stay away from it. Nevertheless, anemones have a very good "friend", that is hermit crabs.
Hermit crabs and anemones are "close friends" who coexist with each other. When anemones release "petals"-tentacles to catch small animals, they not only protect hermit crabs, but also provide them with food. Hermit crabs can swim to the bottom of the sea with anemones. In this way, the two "friends" could not bear to be separated, even when the hermit crab moved, they had to move their "friends" into another snail shell.
Anemone is actually the "home" of jellyfish, jellyfish and coral, belonging to coelenterates. As mentioned above, anemones and hermit crabs live together. Not only that, anemones also made "friends" with a colorful clown fish in the ocean. Anemones are harmless to this clown fish. This clown fish often attracts other shrimps and small fish to participate in this activity. Anemones will catch them and have a good meal with this clown fish. In addition, there is a parasitic shrimp that has contact with anemones. Parasitic shrimp "combs" anemones' tentacles to keep them clean. The reward of parasitic shrimp is that it is "combed" into food waste. Therefore, this transparent, glassy parasitic shrimp is called "sunflower shrimp". Don't look at these anemones. They are clumsy. They can actually "settle down" on the thorns of cancer and let crabs take them to travel to the sea world. To be honest, they will "settle" on the back of crabs. So sometimes fishermen can catch anemones when they catch sea crabs.
Anemone, small 1mm, large1mm. Generally speaking, anemones living in tropical waters are bright in color and large in size, while in cold waters, they are monotonous in color and small in size.
In the world, the king squid that dares to compete with the sperm whale is nearly 17 meters long, the blue whale that landed in the Falkland Islands in South Africa is 33 meters long, and the jellyfish that floats in the northern waters is 36 meters long, but these animals are not the longest animals in the world.
In, after a violent storm, a marine newworm, also known as a worm, was collected off the coast of Scotland, and its body length was measured to be over 180 feet (about 55 meters)! It was identified as a huge new bug. It is not enough to call it a super new bug. According to Tong Zhi, there are more than 500 new worms in the world.
However, although the super newworm is the largest in the world in terms of body length, it is in a low position in the animal kingdom and is not a noble family in marine life.
Newton worm's body is not segmented, its back and abdomen are flat, and both sides are symmetrical. Structurally, whether it is tens of meters long or only a millimeter long, there is a special kiss. Kiss is located in a special cavity on the back, almost more than half of the body length. When a new salamander preys, its snout can suddenly stretch out and quickly entangle its prey and roll it into its mouth when the arrested person is unprepared. Some salamanders also have acupuncture on their snouts to enhance their predation ability.
In the process of animal evolution, salamanders don't have mouths and anus like flatworms, but have a complete digestive system and an organ specially designed for excreting feces-anus. Its circulation system has also begun to take shape. Newton, as a lower animal, can survive to this day, perhaps because it has the above organs. Newt has a strong vitality, even in the cold winter, it can be stiff and immortal. It has a very thick muscle layer and its body surface can secrete very acidic mucus. There are many tissue cells between its intestine and body wall, which can store food. Therefore, Newton worms have strong hunger tolerance.
Newtonian worm has special regenerative ability, and it reproduces asexually in the form of fracture. Insects can be divided into many parts, and each part is the origin of new individuals in the future. Someone has done this experiment, cutting a newworm body with a length of 10 cm into 100 segments, and after a period of time, each segment has formed a complete individual. Of course, the regeneration ability of different kinds of salamanders is not exactly the same. Some new worms can regenerate as long as they have some longitudinal nerve trunks, while others need to regenerate at the back end of their bodies.
Newtonian worms are mostly brightly colored, with red, blue, yellow, green, white and other colors mixed together, sometimes in the form of cross stripes, and sometimes with special warning colors. If you turn over the rocks in the intertidal zone, you may see some twisted new worms. However, it is still a difficult problem to bring the salamander back to the laboratory for fixation and preservation, even if it is relaxed with special anesthetics, it is difficult to obtain ideal specimens. Newborns have strong contractility. If people put crab nets in the sea, they will smell the food inside and squeeze in along the nets much thinner than their bodies, and then squeeze out after eating the food, which will not do any harm to their bodies.