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用直接法制备的姜片吸虫雄性生殖腺染色体染片中,可见精原细胞分深、浅色两型。初级精母细胞由浅色精原细胞产生,需经过两次成熟分裂才能产生精子。 第一次成熟分裂分前、中、后、末四期。前期发育时间长而复杂;中期细胞可见7条单倍体染色体(n=7);其中大型中部着丝粒染色体1条,中型中部着丝粒染色体3条,小型中部着丝粒染色体2条,小型顶端着丝粒染色体1条。末期细胞分裂为两个次级精母细胞。 第二次成熟分裂由次级精母细胞产生精细胞,有核32个,呈圆形、梭形和弯梭形,由后者发育为32个精子。
Direct method of preparation of the ginger gondii gonadal chromosomes, we can see the spermatogonia sub-deep, light-colored two types. Primary spermatocytes are produced by light-colored spermatogonia that require two mature divisions to produce spermatozoa. The first mature split points before, during, after, the last four. Seventeen haploid chromosomes (n = 7) were observed in metaphase cells, including one large central centromere chromosome, three middle centromeric chromosomes, two small centromeric chromosomes, Small apical centromeric chromosome 1. Terminal cells divide into two secondary spermatocytes. The second mature division produced by the spermatocyte secondary sperm cells, a nucleus 32, was round, fusiform and curved spindle, which developed into 32 sperm.