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Introduction of squid
Cuttlefish is also called squid, cuttlefish and mullet. The doer is called Mingyu. Cephalopod is a widely distributed mollusk, which is distributed in China, Korean, Japanese and European coastal areas, among which Zhoushan Islands in China is the most abundant. Cuttlefish, fish eggs and spine (called cuttlebone in Chinese medicine) can all be used as medicine. Li Shizhen called cuttlefish "blood medicine", which is the treasure of women with blood deficiency anemia and amenorrhea.
In the vast East China Sea, there is such a creature that swims like a fish, but it is not a fish. People used to call it "squid" or "cuttlefish". It is one of the famous seafood products in China. In Zhejiang, it is called "four economic fish" together with large yellow croaker, small yellow croaker and hairtail, and is deeply loved by consumers.
Cuttlefish is not only fresh, crisp and refreshing, but also rich in protein, which has high nutritional value and medicinal value. Braised soup with dried cuttlefish and mung bean can improve eyesight and reduce fire. The scientific name of "squid plate" is "cuttlefish bone", which is also a common medicinal material in Chinese medicine, and it is called "cuttlebone". However, the famous "squid" seems to be a fish rather than a fish, without the basic characteristics of fish (such as bones, scales, fins, etc. ). Why is it called "fish" again? What kind does it belong to?
Squid is a large carnivorous mollusk, which is different from ordinary shellfish and has its own evolutionary process. The familiar shellfish, because they carry heavy shells, or bury them in the beach, or climb on rocks, or attach them to fixed objects with enough silk, are waiting for rabbits to filter tiny zooplankton, so the range of activities is very small and the moving speed is very slow; However, in order to take the initiative to attack and grab nutritious food, squid needs more room to move, so its appearance has changed greatly after a long evolutionary process.
In order to adapt to swimming, its body is gradually oval and its abdomen is flat; The hull degenerates into calcareous ship, which is wrapped by more and more developed outer film to form trunk; When doing fast movement, there is no swinging function of fish tail fin. We use the hydraulic principle to push the body forward by spraying a water column through the mouth, and the instantaneous swimming speed can exceed that of ordinary fish. Especially when encountering enemy's harm, it not only makes a reverse escape like a rocket, but also releases a "smoke bomb" to spray "ink" from the ink sac, creates a barrier, confuses the other side, and then escapes; Moreover, "ink" contains toxins, which can be used to paralyze the enemy and play a strong defensive role. But this kind of "ink" needs to be stored for a long time, so cuttlefish will not spray "ink" easily unless absolutely necessary. Usually, when the squid roams, it usually moves forward by its fleshy wings and head and wrist. They are both "two-way athletes" and "reverse sprinters".
The basic structure of shellfish is: the body is soft, not segmented or pseudo-segmented, and usually consists of five parts: head, feet, trunk (visceral sac), mantle and shell; In the mouth, there are jaws and toothed tongues in addition to petabranchia; The nervous system includes ganglion, nerve cord and nerve ring around esophagus. The body cavity retreated to the pericardial cavity. Therefore, squid must be a kind of shellfish, belonging to mollusk, Cephalopoda, Decapoda, sepiidae.
Squid is a delicious seafood ingredient commonly used by human beings. It can be fried or eaten raw. Common dishes include cuttlefish balls, cuttlefish rolls, fried cuttlefish, salted cuttlefish, seafood soup and so on. Sometimes paella is used. There are also cuttlefish noodles cooked by Hakodate in Japan with raw cuttlefish.
Squid shell contains calcium carbonate, chitin, mucus, and a small amount of sodium chloride, calcium phosphate, magnesium salt and so on.
The ink secreted by squid contains a mucopolysaccharide (glycosaminoglycan), which has been proved to have a certain degree of cancer inhibition effect on mice by experiments.