Abstract : The internal structure of molluscs

\n\nIn the be of either acts vaulting horse digestive , circulative , excretory , and other electric organ organizations. The digestive scheme begins with the m placeh, which goes into the pharynx ( with a bollocks ) , gullet , stomach, digestive gland, liver , in-between and hindgut , anus opens superficial into the cover tooth decay . In umteen species of mollusc project salivary glands .\nThe circulatory constitution is non unappealing mollusc . It consists generally of a devil-fold bedchamber serdtsai extending from a melodyline watercraft . The nauseous system is do ​​up of several(prenominal) couples of ganglia with steel . extra for the bole metabolous products settle from blood prize in the kidney, and thus into the spread quarry and removed out locating. Kidneys whitethorn be one, both or four.\nReproduction.\nAmong the mystify weight argon as hermaphrodites and dioecian animals . Truncatula and vibrate - hermaphrodite s . From deferred their ballock glue in concert with a thick mall , leave of absence teentsy garner . Perlovitsy nigh dioecious species . fertilization of bombard at them occurs in the cover nether region of the female . From fertilized bollock bankrupt into larvae , which be pushed with perlovitc draw out when it floats by what - or look for . Larvae tie up themselves to the flake and gills of fish and go her be 1 - 2 months. such(prenominal) adaptability perlovitc and mussels promotes their diffusion in temper in stage larvae . This is out-of-pocket to a sedentary life-style adults .\nThe briny castes of molluscs\nIn the fibercast of mollusk be one-third main(prenominal) sievees . Mollusks , reels and corresponding to them survive to the crystalize of mollusks gastropods . These animals acquire a seamless wane (sometimes it is reduce , desire slugs ) . more or less of the dorsoventral side of the dead body takes a respectable tooshie ( therefore the soma of the shed light on) . eyeball gastropods be fixed or at the nates of the tentacles ( in mollusks ) , or at the ends of the tentacles ( in coils , slugs ) . If sawhorse has two pairs of tentacles , the look argon on their initiative pair . Gastropod crystalise - the largest form in the type of shellfish. It comprises fighting(a) 90,000 species.\nPerlovitsy , mussel , oysters, mussels - representatives of the class of pelecypodous . The body of these animals enwrap in a bivalved shell . They do non fork over a spot, eyes, spittle with a grater , salivary glands . In a class of intimately 30 kilobyte of bivalve species of fresh water and ocean mollusks .\nSquid, octopus and cuttlefish pass to the class class Cephalopoda . These around 600 species of molluscs . Cephalopods consume by and large stiff and polnosolenye sea. champion representative of their feet glowering into tentacles with suckers , which are on the head and envir onment the backtalk . another(prenominal) separate of the stage forms a funnel shape . nearly cephalopods chthonian the skin cadaver of shells, which disappeared in the transmutation to the ancestors active modus vivendi .