食蚊鱼卵子发生的组织学观察

食蚊鱼卵子发育过程分为6个时相。第1时相,卵原细胞细胞质较少,核质比较大。第2时相,卵母细胞体积增加迅速,核质比显著减小,细胞质强嗜碱性,滤泡细胞出现。到晚期,有卵黄核及类生长环的出现,这两种结构均和卵黄物质的形成有关。第3时相,卵母细胞嗜碱性减弱,卵黄泡从膜内缘开始出现,逐渐充满细胞质。颗粒层滤泡细胞互相堆积成舌状镶嵌入卵膜,并使放射带凹凸不平,称为镶嵌型滤泡。第4时相,卵母细胞体积增加较快,卵黄泡消失,卵黄物质逐渐充满细胞质,细胞核移至边缘。第5时相,滤泡细胞脱落,成为成熟卵,卵黄物质均匀散布,卵膜极薄。第6时相,未受精卵和滤泡细胞逐渐退化,被吸收。

Histological Studies of the Oogenesis of Gambusia affinis

The oogenesis of Gambusia affinis is divided into 6 phases.In the first phase,the oogonium has little cytoplasm and bigger nuclear-cytoplasmic ratio.In phase 2,the volume of oocytes increases rapidly while the nuclear-cytoplasmic ratio decreases obviously,the cytoplasm is in a strong basophilia state,and the follicular cell starts to appear.To the late stage of this phase,yolk nucleus and mimetic growth circle which both would be relate to the formation of yolk matters appears.In the third phase,the basophilia of the oocytes gets weaker,and yolk bubble which the cytoplasm is gradually filled with is first seen in the inner edge of the membrane.Follicular cells which pile up as a tougue in the granular layer come to insert into egg membrane,and make the zona rediata undulate.This kind is called inlayed-folicle.In phase 4,the increase of oocyte volume gets sooner,the yolk bubble disappears,and cytoplasm is gradually filled with yolk and with nucleus moving to age.In phase 5,the follicular cells fall off and the eggs mature with characters of very thin membrane and well-distributed yolk.In phase 6,unfertilized eggs and follicular cells degenerate gradually and are absorped at last.