CAJ | 학술논문

采用组织学方法较为系统地研究了隆线溞(Daphnia carinata)孤雌卵(夏卵)胚胎发育的全过程.隆线溞夏卵为中黄卵,室温24 ℃下,整个胚胎发育过程需45 h左右.根据隆线溞胚胎内部结构特征及外部形态学变化,将其胚胎发育分为卵裂期、囊胚期、原肠期、前无节幼体期、后无节幼体期、复眼色素期和准备孵化期7个时期.卵排至孵育囊约40 min后开始表面卵裂.卵裂至256细胞时,胚胎发育进入囊胚阶段,在卵表形成一薄层细胞层,囊胚腔则全被卵黄颗粒所充塞.囊胚后期,囊胚层细胞分裂加快,相互挤压向囊胚腔中移入形成原肠胚.随后,胚胎外部形态开始出现变化.首先在胚胎前端出现头部的三对附肢原基(两对触角原基及一对大颚原基),胚胎发育进入前无节幼体期;随后胸节分化,胚胎发育进入后无节幼体期,并形成胸肢、壳瓣和肠道等结构.复眼在复眼色素期的基础上,逐渐发育形成完整的复眼结构,同时其他各组织器官也不断发育完善.至准备孵化期的胚胎结构与幼体已基本相同.以上研究结果可为深入研究枝角类胚胎发育的机理积累基础生物学资料.
채용조직학방법교위계통지연구료륭선소(Daphnia carinata)고자란(하란)배태발육적전과정.륭선소하란위중황란,실온24 ℃하,정개배태발육과정수45 h좌우.근거륭선소배태내부결구특정급외부형태학변화,장기배태발육분위란렬기、낭배기、원장기、전무절유체기、후무절유체기、복안색소기화준비부화기7개시기.란배지부육낭약40 min후개시표면란렬.란렬지256세포시,배태발육진입낭배계단,재란표형성일박층세포층,낭배강칙전피란황과립소충새.낭배후기,낭배층세포분렬가쾌,상호제압향낭배강중이입형성원장배.수후,배태외부형태개시출현변화.수선재배태전단출현두부적삼대부지원기(량대촉각원기급일대대악원기),배태발육진입전무절유체기;수후흉절분화,배태발육진입후무절유체기,병형성흉지、각판화장도등결구.복안재복안색소기적기출상,축점발육형성완정적복안결구,동시기타각조직기관야불단발육완선.지준비부화기적배태결구여유체이기본상동.이상연구결과가위심입연구지각류배태발육적궤리적루기출생물학자료.
The parthenogenetic egg (PE) is centrolecithal and its embryogenesis lasts about 45 hours at 24 ℃.According to the morphological and histological changes, the embryonic development of D.carinata could be divided into seven major stages, i.e.the cleavage stage, blastula stage, gastrula stage, egg-nauplius stage, egg-metanauplius stage, embryo with eye pigments, and prepare-hatchling stage.The superficial cleavage of PE did not happen until approximately 40 minutes after egg laying.At the end of cleavage, the embryo consisted of 256 cells and reached the blastula stage at which a large part of the blastocoele was filled with yolk granules, accompanying by the formation of a thin sheet of divided cells.The cell division rate was accelerated and gastrulation took place by means of immigration of blastodermal cells at the end of this stage.Afterwards, the morphological changes in embryo development became remarkable.The egg-nauplius stage was characterized by the appearance of the rudiments of two antennae and a mandible in the head region of the embryo, while the egg-metanauplius stage characterized by the formation of the thoracic segments, thoracic limbs, carpace, and guts.At the eye pigments stage, the embryo was found presenting the eye pigmentation in the well-developed compound eyes.Simultaneously, other physiologically important tissues and organs started to develop.During the last prepare-hatching stage, the organelle structure in the embryo could be quite similar to that in the larval.The results could accumulate basic biological information for further research on embryonic development of Cladocera.