减数分裂

In order to develop a new path for gene mapping of fish, the digoxigenin and tritium labeled in situ hybridization techniques combined with multiple banding analysis on the pachytene bivalents of M. albus were studied using the wheat ribosomal RNA genes, pig growth hormone gene and MaSoxl (M. albus SRY boxl) DNA segment as the probes. Moreover, the techniques of random primed in situ DNA synthesis were also developed on the bivalents of M.

以两种异源基因和Ma Soxl为探针，采用地高辛或氟标记的原位杂交技术，结合点渍法和DNA印渍法分析，率先在黄鳝减数分裂二价体上开展基因定位研究，并与多重带带型分析相结合，以期为构建黄鳝染色体框架图奠定初步基础，为迅速改变鱼类基因定位研究的落后局面而开辟新的途径。

Thus, the meiotic chromosome cofigurations showed that the tetraploids and hexaploids in C.reticulata allopolyploids, and the appearance of a few tetravalents in some populations might indicatehomology of chromosomes in different genomes to some extent.

根据减数分裂的构型，我们认为，四倍体和六倍体分别为异源四倍体和异源六倍体，少数四价体的存在表明染色体有部分同源性。

In meiosis of pollen mother cells of the tetraploids and the hexaploids, only bivalents were observed in most of the populations, although in several populations or individuals a few univalents or tetravalents appeared. In the hexaploids, hexavalents were not observed.

四倍体和六倍体的花粉母细胞减数分裂染色体构型在大多数居群都为二价体(四倍体中30个二价体，六倍体中45个二价体)，少数居群或是个体除二价体为主外还出现单价体和四价体，六倍体类型没有出现六价体构型。

Linkage groups can be broken up by CROSSING OVER at meiosis to give new combinations of genes.

连锁群在减数分裂中通过联会交换被打破而产生基因重组。

This review is focused on the recent research progresses of related genes in the development of embryo, endosperm, and miosis, and several genes may involved in the regulation of apomitic development.

本文介绍了植物胚发育、胚乳发育、减数分裂等涉及无融合生殖过程的相关基因的研究进展，同时介绍了可能与植物无融合生殖途径调控相关的几个基因片段的研究情况。

The extra divisions or fusions appearedonly in some flower buds of one plant, some anthers in the same buds, or even inindividual cells of tetrads.

六倍体Ⅲ和诸葛菜杂种的一个单株中，减数分裂粗线期之前未见异常，粗线期之后，染色体缺少配对的过程，单价体聚集在一起。

Hytivus. Although chromosome number of all materials studied was counted to be 2n = 38, the difference in meiotic behaviors between individuals of first selfed progenies were observed, which indicated the difference in the degree of diploidization.

虽然染色体记数的结果表明所有单株的染色体数目都为38条，但是花粉母细胞的减数分裂行为在单株间的细小差异也被观察到了，这表明各单株间存在较小的二倍化程度的差异。

The topics in this lab course include the following areas: Microscope and cell morphology, Cell Physiology, Enzymes, Mitosis and meiosis, Cellular respiration, Photosynthesis, Mendelian genetics, Prokaryotes, Protists, Fungi and lower Plants.

本学期课程包含显微镜介绍、各种动、植物细胞形态及构造、细胞生理现象、酵素反应、细胞有丝及减数分裂、遗传性状、细胞呼吸作用、光合作用、原核生物形态、原生生物形态、真菌形态及苔藓植物形态。

In the present study, we collected cumulus cells oocyte complex from ovaries of two different strain mice. The cumulusenclosed oocytes were cultured for 6 h in MEM supplemented with growth factor and FSH. The meiotic maturation of these oocytes has progressed to pro-metaphse Ⅰ stage and the condensed chromosomes are visible under DIC microscope, metaphase Ⅰ spindle even can be detected under Polscope. The metaphase Ⅰ spindles of oocytes were exchanged under such microscopes. After electric stimuli, 91. 6% and 91. 6% karyoplasts-cytoplasm pairs were fused respectively. The resulting oocytes were cultured further in MEM and over 80% of oocytes released the first polar body. 79% and 77% of oocytes formed two pronuclei after in vitro fertilization and the embryos were cultured in KSOM supplemented with amino acids. Over 60% of embryos developed to blastocyst stage.

在本研究中我们在取得两种不同品系小鼠的卵丘卵母细胞复合体后，先将卵丘卵母细胞复合体置于含有多种生长因子和激素的MEM培养液中培养6小时，此时卵母细胞已进入第一次减数分裂的前中期，并且在DIC倒置显微镜下可以看到浓缩的染色体，用Polscope可以发现明显的纺锤体，借助这种显微镜通过显微操作将两种不同品系小鼠来源的卵母细胞的MI纺锤体进行互换，经过三次直流电脉冲作用后，分别有91.6％的胞质—MI核质体对融合，经过进一步的培养后，超过80％的重组卵母细胞排出第一极体，体外受精后分别有79％和77％的重组卵形成双原核，受精后的胚胎在KSOM胚胎培养液中体外培养4天后，超过60％的胚胎发育至囊胚。

The purpose of this laboratory is to train undergraduate students with practical genetics, including the basic principles of genetics, inheritance of pea traits, root tip chromosomes, Drosophila salivary polytene chromosomes, meiosis, statistical methods, bacterial antibiotic resistance, plasmid isolation, restriction, and gel electrophoresis, blood type, and human genetics.

遗传学实习 1 必陈福旗，戴国兴本课程之目的，在使学生透过实际操作与试验，了解遗传学之原理，实验内容包括：碗豆七个性状遗传，植物根尖染色体观察，果蝇唾腺染色体，减数分裂，统计方法，细菌抗药性，质体之抽取及限制酵素切割及电泳分离，血型，人类遗传。

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。