有性生殖

Phenotypic plasticity and genetic differentiation are the two major strategies that alien invasive plants can adapt habitat heterogeneity.The polymorphism of invasive plants and the diversity of their dispersal way enable them occupying invaded habitat quickly,and dispersing with a far range.The breeding strategies that agamogenesis and amphigenesis can coexist and trade off according to the habitat and invasive stage can not only promote the invasive population erupted massively,but also directly affect the dispersal mechanism and regulate the genetic structure of the population.

表型可塑性和遗传分化是外来入侵植物对生境异质性的两种适应策略；散布体多态型和散布途径多种化，使外来入侵植物迅速占领入侵生境，并进行远距离扩散；无性生殖和有性生殖并存，并根据生境和入侵阶段权衡的繁育对策不仅使入侵种群大面积暴发成为可能，而且直接影响散布机制并对种群遗传结构具有调节作用。

1Both sexual and apomictic embryo sacs were co-existed which belonged to facultative apomixis.

2在有性生殖胚囊中，可观察到完整的八核胚囊。

These species time their sexual reproduction with periods of environmental uncertainty, and reproduce asexually when conditions are more favourable.

这些物种按环境不确定的时期安排它们有性生殖的时间，当条件较为有利时它们进行无性繁殖。

If sharks in the wild are reproducing asexually, their young will be genetically weaker than those produced sexually.

如果野生鲨鱼也用无性生殖的方式繁衍后代，那么他们的后代与有性生殖的后代相比更为脆弱。

It is suggested that autotetraploidy rices are better females in the distant hybridization due to the fact that they are weaker in sexually reproductive ability.

结果暗示由于同源四倍体水稻具有比较弱的有性生殖能力，在远缘杂交中它们是比较好的杂交母本。

Male gametogenesis is one of the key steps in plant sexual reproduction and is essential for the alternation between the diploid sporophytic phase and haploid gametophytic phase in the life cycle of higher plants.

植物雄配子体发生和发育是有性生殖的关键步骤之一，是高等植物通过有性生殖进行世代交替所必需的。

Monogony is a special kind of sexual reproduction.

紫菜的生殖主要有无性生殖和有性生殖，单性生殖是一种特殊的有性生殖。

Peronosporales An order of the OOMYCOTA characterized by sexual reproductionby zoospores and sexual reproduction by zoospores produced from oospores.

霜霉目：以游动孢子的有性生殖和由卵孢子产生的游动孢子的有性生殖为特征的卵菌门的一个目。

Alternatively,有性生殖 may allow for the ' ratcheting ' of evolutionary speed as one clade competes with another for a limited resource .

或者，有性生殖可能象'棘轮'那样控制了进化发展的速度，因为一个进化枝会和另一个竞争有限的资源。

And its types of reproduction includes asexual and sexual reproductions.

植物的有性生殖。5。而无需有性生殖中的基因混合。

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。