动物学报
動物學報
동물학보
ACTA ZOOLOGICA SINICA
2001年
2期
182-185
,共4页
康现江%王所安%堵南山%赖伟
康現江%王所安%堵南山%賴偉
강현강%왕소안%도남산%뢰위
中国对虾%受精%精核%卵核%细胞学
中國對蝦%受精%精覈%卵覈%細胞學
중국대하%수정%정핵%란핵%세포학
中国对虾精子以其棘部顶端随机附着在卵上,精子在凝胶膜形成后,第一极体排出前入卵。精子入卵后,絮状的精核经过重建形成雄原核。中国对虾卵子排放时处于第一次成熟分裂的中期,卵子入海水时,纺锤体的长轴与质膜平行。卵子激活后,纺锤体的长轴开始旋转,旋转至纺锤体长轴与质膜垂直时,由纺锤丝牵引着染色体向两极移动,外侧的染色体由质膜包裹形成第一极体。受精膜举起后,由次级卵母细胞排放出第二极体。此后,单倍雌核重建形成雌原核。雄原核形成早于雌原核, 雌雄原核于卵子中央联会形成联合核。受精后约50分钟纺锤丝牵引着染色体移向两极, 质膜内缢断裂形成两个细胞的胚胎。
中國對蝦精子以其棘部頂耑隨機附著在卵上,精子在凝膠膜形成後,第一極體排齣前入卵。精子入卵後,絮狀的精覈經過重建形成雄原覈。中國對蝦卵子排放時處于第一次成熟分裂的中期,卵子入海水時,紡錘體的長軸與質膜平行。卵子激活後,紡錘體的長軸開始鏇轉,鏇轉至紡錘體長軸與質膜垂直時,由紡錘絲牽引著染色體嚮兩極移動,外側的染色體由質膜包裹形成第一極體。受精膜舉起後,由次級卵母細胞排放齣第二極體。此後,單倍雌覈重建形成雌原覈。雄原覈形成早于雌原覈, 雌雄原覈于卵子中央聯會形成聯閤覈。受精後約50分鐘紡錘絲牽引著染色體移嚮兩極, 質膜內縊斷裂形成兩箇細胞的胚胎。
중국대하정자이기극부정단수궤부착재란상,정자재응효막형성후,제일겁체배출전입란。정자입란후,서상적정핵경과중건형성웅원핵。중국대하란자배방시처우제일차성숙분렬적중기,란자입해수시,방추체적장축여질막평행。란자격활후,방추체적장축개시선전,선전지방추체장축여질막수직시,유방추사견인착염색체향량겁이동,외측적염색체유질막포과형성제일겁체。수정막거기후,유차급란모세포배방출제이겁체。차후,단배자핵중건형성자원핵。웅원핵형성조우자원핵, 자웅원핵우란자중앙련회형성연합핵。수정후약50분종방추사견인착염색체이향량겁, 질막내액단렬형성량개세포적배태。
When a female prawn spawns, stored spermatozoa were released from the thelyc um and mixed with the eggs by the beating of the pleopods. The spermatozoa binde d the egg with their spike top by random. At the time when the jelly coat was fo rmed, and before the first polar body was emitted, the sperm penetrated into the egg by crossing the plasma membrane. After the sperm penetrated into the egg, i ts nucleus was transformed into a big male pronucleus.
The eggs of the prawn at spawning were in meiotic metaphase Ⅰ stage, and the meiotic apparatus was positioned parallel to the egg surface. After the egg was activated, the meiotic apparatus rotated and positioned perpendicularly to the e gg surface. The chromosomes drawn by the spindle microtubule separated. The chro matin near the plasma membrane was surrounded and formed the first polar body. A fter fertilization membrane was lifted, the secondary egg emitted the second pol ar body into the perivitelline space.
Following the extrusion of the second polar body, the haploid female chromat in formed a female pronucleus.The male pronucleus formation was earlier than the female〖DK1〗's. The male and female pronuclei moved to the center of the egg, and mat ched into a association nucleus. The chromosomes of the first mitotic apparatus separated 50 min after fertilization and 2cell embryo was formed by plasma mem brane invagination.