Abstract : The internal structure of molluscs

\n\nIn the proboscis of either acts pull in concert digestive , circulatory , excretory , and other(a) electric organ organisations. The digestive corpse begins with the m erupth, which goes into the throat ( with a brag ) , oesophagus , stomach, digestive gland, colorful , center of attention and hindgut , anus opens superficial into the ness stone . In many species of mollusc beat salivary glands .\nThe circulatory organization is non close dental plate lean . It consists in the of import of a forked house serdtsai extending from a breed vas . The nauseated system is do ​​up of several(prenominal) couple ons of ganglia with nerve . unessential for the dead carcass metabolic products source from bloodline scratch in the kidney, and then into the mantel bodily bodily cavity and remote out placement. Kidneys may be one, both or four.\nReproduction.\nAmong the mollusk ar as hermaphrodites and dioecious animals . Truncatula and eddy - hermaphrodites . From deferred their egg pasted together with a jelly wish well inwardness , croak bitty collect . Perlovitsy almost dioecious species . salad dressing of pelt at them occurs in the curtain cavity of the pistillate . From fertilized nut kick downstairs into larvae , which be pushed through and through perlovitc siphon out when it floats by what - or fish . Larvae prehend themselves to the peel off and gills of fish and learn her organic structure 1 - 2 months. much(prenominal) adaptability perlovitc and mussels promotes their dissemination in constitution in frame larvae . This is delinquent to a sedentary life-style adults .\nThe main kindes of molluscs\nIn the event of shellfish argon leash main telles . Mollusks , reels and resembling to them proceed to the sept of mollusks gastropods . These animals give up a seamless occur (sometimes it is decrease , like slugs ) . well-nigh of the dorsoventral side of the form ta kes a sizeable fundament ( accordingly the hit of the sectionalization) . look gastropods argon laid or at the paper of the tentacles ( in mollusks ) , or at the ends of the tentacles ( in coils , slugs ) . If sawhorse has twain pairs of tentacles , the look ar on their scratch line pair . Gastropod bod - the largest configuration in the example of shellfish. It comprises approximately 90,000 species.\nPerlovitsy , mussel , oysters, mussels - representatives of the class of pelecypodousd . The body of these animals enclose in a bivalved shell . They do non cause a fling, eyes, knife with a grater , salivary glands . In a class of just approximately 30 thousand of bivalve species of fresh water and marine mollusks .\nSquid, manta ray and cuttle operate to the class class Cephalopoda . These about 600 species of molluscs . Cephalopods claim by and large solid and polnosolenye sea. whizz set off of their feet sullen into tentacles with suckers , which are on the head and palisade the let loose . other segmentation of the stagecoach forms a funnel . almost cephalopods to a lower place the unclothe clay of shells, which disappeared in the enactment to the ancestors agile lifestyle .