有性生殖

It contains two types of nuclei in each cell, one isgenerative micronucleus, a typical diploid, meiotic germ-line nucleus, andanother one is vegetative macronucleus, a highly specialized expressionorganelle that provides all the transcripts for cell function.

其具有一个无转录活性的生殖核，负责有性生殖过程中遗传物质的传递；一个具转录活性的营养核负责细胞营养生长过程中基因的表达。

Interval observations under thefluorescent microscop were performed with excition waves of 470—490 nm.The results displayed that GFP genes were expressed effectively in E.octocarinatus, and GFP was distributed unifimly around macronuclearand diffused to the entire cell gradually. The chromosomes can be kept inthe macronucleus for 90h.

用优化的脂质体转化方法将含有人工染色体的重组质粒pBTub-tel2转化到处于有性生殖分裂间期阶段的游仆虫细胞中，结果表明，GFP基因在游仆虫细胞中得以高效表达，36-48小时绿色荧光均匀分布在细胞核周围，逐渐扩散到整个细胞，染色体能够在大核中保持约90小时。

In sexually reproducing organisms like us, a process called meiosis halves this number.

在象我们这样的有性生殖生物体中，称为减数分裂的过程平分了它的数目。

Processes originated One-celled life reproduces by splitting, but sexual reproduction is much

一个单细胞的生命藉分裂而产生新细胞，那么有性生殖会是更复杂的问题了。

The highest oocysts producing period occurred in April, and the highest oocyst hatching and density of population was in May. And the sexual reproduction process had relation to temperature, food and size of planarians.

卵囊产出的高峰在4月，卵囊孵化与种群密度最高峰在5月，其有性生殖过程与温度、食物、虫体大小密切相关。

Outcrossing, the second fundamental aspect of sex, is maintained by the advantage of masking mutations and the disadvantage of inbreeding which allows expression of recessive mutations (commonly observed as inbreeding depression).

有性生殖的第二个基本方面是异型杂交。异型杂交是通过掩蔽突变优势和近亲繁殖劣势来维持的。近亲繁殖允许隐性突变的表达。这与查尔斯·达尔文相一致。

Although the cloned child will carry the same problem genes as the parent who donates the nucleus, he or she will in all likelihood enjoy the parent's state of health and will be free of the additional risks caused by mixing both parents?genes during sexual reproduction.

尽管被克隆的孩子也会携带捐赠细胞核的父亲的问题基因，但是他们十有八九会享有和父亲一样的健康，并且在有性生殖的时候也会避免因为混合了父母的基因而造成的另外的危险。

Due to the causes such as polyploidy and self-incompatibility, the plants of Paspalum, with the greatest number of apomictic species, show much complex and various reproduction characteristics.

由于多倍体的存在及有性生殖的自交不亲和等原因，雀稗属植物表现出复杂多样的生殖特性，是禾本科中具备无融合生殖特性种类最多的属。

Due to the causes such as polyploidy and self-incompatibility,the plants ofPaspalum,with the greatest number of apomictic species,show much complex and various reproduction characteristics.

由于多倍体的存在及有性生殖的自交不亲和等原因，雀稗属植物表现出复杂多样的生殖特性，是禾本科中具备无融合生殖特性种类最多的属。

The daughter cells contain half no.of chromosome of the parent cell.Therefore it is also called reduction division.

减数分裂是在进行有性生殖的生物中导致生殖母细胞中染色体数目减半的分裂过程。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。