减数核

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。

F1 hybrid has the morphological feature which is between the male and female parents and shoed strong heterosis, exuberant vitality, late ripe period and low rate of self-fertility. The average chromosome configuration of F1 in PMC MI was 18.58Ⅰ+18.59Ⅱ+0.085Ⅲ+0.028Ⅳ. At anphase Ⅰ in PMC, some laggard chromosomes arranged in equatorial plate. Micronucleus and a lot of abnormal cells can be observed at dyad, tetrad and microspore.

杂种F1形态特征介于双亲之间，具有较强的杂种优势，生长旺盛，熟期晚，自交结实率较低。F1花粉母细胞减数分裂中期Ⅰ平均染色体构型为18.58Ⅰ+18.59Ⅱ+0.085Ⅲ+0.028Ⅳ，PMC后期Ⅰ观察到部分落后染色体排列在赤道板上；二分体、四分体和小孢子时期，细胞内普遍观察到微核，且出现大量异形细胞。

And the research materials were often meiotic pachytene chromosomes of sex gland and mitotic prometaphase of early embryos and diapause eggs\' somatic cells.

早期，家蚕染色体识别和基因定位研究主要利用性腺减数分裂粗线期的染色体、早期胚胎和滞育卵有丝分裂早中期的染色体作为材料，按照相对长度和部分限性易位系统或缺失等来进行核型分析。

Previous studies have demonstrated that primary spermatocyte can undergo meiotic divisions in MI oocytes and the resulting embryos can develop to term. However, the success rate is very poor.

已经证明初级精母细胞在显微融入MI卵母细胞后可以完成减数分裂并且产生的胚胎可以发育到期，只是发育率还非常低，作为一种形式的核移植，细胞周期的同步化处理对于胚胎的发育具有重要意义。

Disruption of Sun1 in mice prevents telomere attachment to the nuclear envelope, efficient homologue pairing and synapsis formation in meiosis.

小鼠中Sun1基因的剔除破坏了减数分裂时期端粒的核膜附着，阻碍了同源染色体配对和联会的形成。

The result showed that the plant of Maicao No. 9 was tall, with good fecundity, fully filled grain and vigorous growth. The chromosome number of the root cells was 2n=56, through the observation of pollen mother cells meiosis, there were a certain amount of univalents, ring bivalents and bar bivalents in PMCM. Different numbers of lagging chromosomes, chromosome bridges and micronucleus were found in anaphaseⅠ, anaphaseⅡ and tetraspore.

结果表明：麦草9号植株高大，结实性较好，籽粒饱满，生长旺盛；根尖细胞染色体数目为2n=56，对其进行花粉母细胞减数分裂观察，中期Ⅰ具有一定数量的单价体、环状二价体、棒状二价体；后期Ⅰ、后期Ⅱ与四分体时期都出现不同数量的落后染色体、染色体桥、微核等现象。

The observation showed that sterile plants and fertile plants in the pollen mother cell stage is not very different, when microspore mother cells of male sterile plants enter meiosis period, it could form normal tetrad cell , tetrad cell is normal in early development stage, In the uninucleate microspore stage , tapetal cells were vacuolization, the microspores were extruded to the middle by tapetal cells.

本研究利用石蜡切片法，结合光学显微镜技术对樱桃萝卜核质互作雄性不育系的不育株和对应保持系可育株的花药发育过程进行细胞形态学观察，观察结果表明：不育株与可育株在花粉母细胞时期差别不大，不育株的花药小孢子母细胞进入减数分裂期后，可以正常的形成四分体，四分体前期发育正常，而在单核小孢子期绒毡层细胞出现液泡化，绒毡层细胞向中间挤压小孢子。

Genetic diversity in 12 populations of apomictic Eulaliopsis binata was evaluated by morphological observation and RAPD analyse ,as a result, 12 populations of E.binata were divided into different types.

通过分析龙须草核型和观察花粉母细胞减数分裂过程中染色体行为与变异，判断其倍性水平和多倍体类型。

During conjugation, the complementary mating type cells unite pairwise undergo meiosis, exchange gametic nuclei and separate again.

在接合生殖期间，交配型互补的细胞相互识别配对，进行减数分裂、交换配子核，然后分开。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。