查询词典 meiosis

Tetraploid organisms may arise by the fusion of two diploid gametes that have resulted from the nondisjunction of chromosomes at meiosis, or by nondisjunction of the chromoosomes during the mitotic division of a zygote.

四倍体的产生可能是由于两个二倍体配子发生融合，这种二倍体配子又是在减数分裂中染色体不发生分离而形成。四倍体也可能因为受精卵进行有丝分裂时染色单体未发生分离而形成。

In the conjugation pair, the normal cell can finish the normal meiosis process, the gametic nuclei fused, the zygotic nucleus divided and at last formed two cells with micronucleus.

对上海四膜虫有小核细胞和无小核细胞的接合过程进行了跟踪观察，发现在四膜虫中也存在胞质配合。

In meiosis, the association of four homologous chromatids seen during the pachytene stage of prophase.

减数分裂前期的粗线期中，四个同源的染色单体向联系形成的结构。

Pachytene in MEIOSIS ,the stage in mid-prophaseⅠ that is characterized by the contraction of paired homologous chromosomes.

粗线期：减数第一次分裂前中期中的一个阶段，以配对同源染色体浓缩为特征。

Pairing of homologous chromosomes commences at one or several points on the chromosome and is clearly seen during PACHYTENE of meiosis I.

同源染色体两两成对平行靠拢，这一现象也称联会，联会发生在染色体的一点或多点上，可以在减数第一次分裂的粗线期观察到。

Before ovulation, primary oocytes complete the first meiosis produce a secondary oocyte and a polar body.

在排卵前，初级卵母细胞完成第1次减数分裂产生次级卵母细胞和第1极体。

As with the male gametes the remaining cytoplasma binding serves the synchronization of the division and maturation of the cells: just as for the 1rst polar body at the time of the termination of the 2nd meiosis.

和雄性配子一样，这些残留的细胞质连接有助于细胞分裂和成熟的同步化：就像第二次减数分裂结束时的第一极体一样。

Puna Chicory, leymus multicaulis and Psathyrostachysjuncea.For the materials used in this article were some old seeds which had been stored for 3-7 years, we found a lot of abnormal mitotic and meiotic cells, such as chromosome bridge. chromosome laggard, micronucleus, multipolar division and so on. Moreover, we also found the wheat"s multi-anther, double germinate-hole"s microspore and collected the photos of every period of meiosis. mitosis.

因为用于细胞学检测的小麦材料是搁置多年的陈旧种子，所以在检测染色体数目时，发现大量异常分裂现象，包括染色体桥、染色体落后、微核、多极分裂等；实验过程中还发现小麦多花药现象和花粉粒具双萌发孔的现象；同时在显微观察同时还注意搜集了细胞有丝分裂、减数分裂各个时期的分裂相图片。

Results showed that the PMC meiosis of autotetraploid was similar to the diploid except some particularities. In metaphase Ⅰ, multivalent, quadrivalent, trivalent, bivalent and univalent were observed and some of the chromosomes were found not to rank on the metaphase plate and so did in metaphase Ⅱ cells. In anaphase Ⅰ and anaphase Ⅱ cells, there were lagging chromosomes, chromosome bridge and fragment. During anaphase Ⅱ and telophase Ⅱ, chromosome segregation was not synchronous or equal. At tetrad stage, dyad, triad, tetrad with micronucleus and polyad appeared.

结果表明，同源四倍体花粉母细胞减数分裂过程与二倍体相比，中期Ⅰ染色体构型复杂，有多价体、四价体、三价体、二价体和单价体；中期Ⅰ及中期Ⅱ有部分染色体没有排列在赤道板上；后期Ⅰ及后期Ⅱ出现落后染色体、染色体桥及断片；后期Ⅱ和末期Ⅱ有染色体不同步分离及不等分裂的现象；四分体时期还出现二分体、三分体、含微核的异常四分体及多分体。

These mainly involve the periodic change of ribosome den- sity,the dedifferentiation and redifferentiation of both plastid and mitochondrion during the process of meiosis.

在这个过程中，小抱子母细胞经减数分裂产生大致相同的4个减数抱子，并逐渐发育成雄配子体。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。