| The fertilized eggs of Hemibnrbus lubco have been observed by SEM, TEM and OM, and main events of fertilization biology have been studied, too. The results suggest:The micropylar apparatus, being composed of vestibule and micropylar tube, is deeply sunken with a short tunnel. External diameter of the micropylar tube is 2. 512 m, and its interior diameter is 2. 330 m, The diameter of sperm is 1. 567 m. Before sperm penetrates, the chromosomes are at metaphase, following prophase and preceding anaphase, during which the chromosomes are aligned along the metaphase plate. About 2s after fertilization in 17 , sperms arrive at micropylar tube; 3s, sperm penetrates into ovum where cytoplasm is sunken; 5s, the spermaster come into being; 20s, fertilization stopper appears; 60s, sperms in micropylar apparatus begin to disaggregate. Now and then, there exists the phenomenon that a few sperms penetrate into egg, while polyspermy is few. 240s, the blastoderm forms in animal hemisphere; 5min, sperm deviates from the sunken area; 8-15min, the chromosome are at anaphase, and 20min, at telophase of meiosis, later, the second polar body can be seen to be expelled; 25min, both the male pronucleus and the female pronucleus can be seen; 30-35min, the female pronucleus move towards the male pronucleus, at the same time, both the pronucleuses move towards the pivot of blastoderm; 40-50min, both the pronucleuses are conjugated into zygote, and then, the zygotic nucleus expands; 70min, chromosomes are situated at metaphase of the first karyokinesis, 80min, at anaphase, and 120min, at telophase, the oosperm is segmentalized into daughter cells. 140min, chromosomes of the daughter cells are situated at metaphase of the second karyokinesis, while the daughter cells don't separate.The egg envelopes are composed of secondary envelope and primary envelope which comprise zona radiatal, zona radiata2 and zona radiata3, and there are tube radiata and flexural sub-elasticity envelope which is vertical with plasma membrane in every zona radiata. About 80s after fertilization, the angle of sub-elasticityenvelope expands. 110s, sub-elasticity envelope in zona radiatal becomes parallel with plasma membrane, later, the same phenomenon happen in zona radiata2 and zona radiata3, which result in the fertilization envelopes (egg envelopes) outspreading; 140min after fertilization, the fertilization envelopes come into being. Three of the zona radiatas gliding together result in fertilization envelopes dilating.There are two types of yolk granule inside of ovum, in which vesicle or arc gap could be observed by OM, and the yolk granule has been decomposed by 4 pathway: (l).be decomposed straight in cytoplasm; (2).begin to be decomposed from the vesicle inside of yolk; (3).begin to be decomposed from the arc gap of yolk; (4).before decomposed, the yolk will be enwrapped by envelope.There are 1 to 4 rows and five types of cortical alveoli in the cortex of Hemibarbus labco. egg From inner to outer of the cortex, the diameter of cortical alveoli decreases gradually. Cortical reaction comprises latent period, developmental period, climactic period and declining period. About 35s after fertilization, a few cortical alveoli begin to discharge from the low-latitudes of the animal hemisphere, later, the same pross happens in the near of micropylar apparatus, and then cortical reaction extends to the animal hemisphere and the vegetal hemisphere. 55s-5min after fertilization, most of cortical alveoli discharge in the animal hemisphere, and the residual cortical alveoli will entirely discharge in 15min. While cortical alveoli discharge in batches, the plasma membrane has been reorganized time after time.Spermaster' elongate and traction, and Cytoplasm' flowage make the male pronucleus and the female pronucleus conjugate. This paper puts forward a hypothesis that sperm will consume energy while entering into ovum to explain the contabescence of the sperm.
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