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一、贝类幼虫的生长过程贝类幼虫是由卵分裂出来,经过囊胚期,进入到原肠期,再进一步变成担轮幼虫。担轮幼虫依靠鞭毛轮的摆动和导航,在水中游动,有趋光性,容易集群。经过一个阶段,壳腺分泌的贝壳质包围了它,呈现一个D形,这时叫D形幼虫。经3天后,它的消化管已形成,便开始进食。进食的方式,主要靠纤毛面盘不断摆动,将水中微小食物旋入口中。经过10天左右,壳顶逐渐隆起,壳形慢慢变化便进入了壳顶幼虫期,这时它的内部器官不断形成、完善。再经过10天左右,即进入到成熟幼
First, the growth of shellfish larvae Shellfish larvae are split off by the egg, after the blastocyst stage, into the original intestine, and then further into the larvae. Troll larvae rely on whiplash wheel swing and navigation, swimming in the water, there is phototropism, easy to cluster. After a stage, the shell gland secreted shellfish surrounded it, showing a D-shaped, then called D-shaped larvae. After 3 days, its digestive tract has formed, they began to eat. The way to eat, mainly by sliver face plate constantly swing, the tiny food into the mouth of water. After about 10 days, the top of the shell gradually bulges, and the shell shape slowly changes and enters the shell top larva stage. At this time, its internal organs continue to form and improve. After about 10 days, that is, into mature young