
n. [胚] 有性生殖
The formation of such a conjugation pair may be concerned with selfing ; the sexual process may be a primitive type of sexual reproduction.
这种接合对的出现可能与自接型有关,其有性过程可能是一种原始的有性生殖类型。
In this sense, there are three types of life cycles that utilize sexual reproduction, differentiated by the location of the organisms phase(s).
由此看出,有性生殖的生物有三种类型的生命周期,其划分标准时生物体时期存在的阶段。
Human beings propagate their species by sexual reproduction.
人类是通过有性生殖来繁衍同类的。
In clones, the genes are effectively tied together like beads on a string. There is no reshuffling as there is during sexual reproduction.
如果是无性繁殖的个体,其基因片段就像珠链一样高效地系在一块儿,不会象有性繁殖时那样发生洗牌似的重组。
The host biotypes have their genetic bases, including the mutation or change in enzymes and chromosomes, sexual reproduction, assortive mating and genetic differentiation of population.
并且具有一定的遗传基础,主要表现在蚜虫体内酶系的变化、染色体变异、有性繁殖中同型交配行为及种群的遗传分化上。
This is one reason why sex matters: when bits of DNA are swapped between chromosomes during sexual reproduction, good and bad variants can be split up.
这就解释了性的重要性:在有性生殖过程中,染色体之间交换DNA比特,良性和恶性变体可以实现分离。
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。
It was suggested that the main reasons for the sexual reproduction abortion in'High Noon' were that it can not form enough viable gametes and lack valid pollination.
认为‘正午’牡丹有性生殖败育的主要原因是不能形成足够多的有生活力的配子和缺乏有效授粉。
Second, normal fungal sexual reproduction usually produces spores, which the immune system can easily identify and dispose of.
其次,普通的真菌有性生殖通常生产孢子,而这些孢子是可以被免疫系统轻易地识别并清除掉的。
To some extent, moderate and heavy grazing can enhance clonal growth ability of grasses, but depress sexual reproduction ability.
在种群水平上,中等强度以上的放牧干扰有利于植物的克隆生长,但有性生殖减弱。
You always want the variation that's present in a natural population going on through sexual reproduction.
我们所希望得到的自然群体的遗传变种一般是通过有性繁殖而产生的。
Provide accurate information on biology and sexual reproduction. Dr. Lynne says you can start talking to your children about this as early as forth grade.
告诉他们正确的生理知识和有性生殖,你可以在孩子四年级的时候开始向他们传授。
The sexual reproduction plant has similar trends too.
有性繁殖植株也有相似的趋势。
Bacteria are capable of sexual reproduction.
细菌可以进行有性繁殖。
Trade-off between clonal and sexual reproduction was not detected during the experimental research.
我们的实验结果未发现克隆繁殖和有性繁殖之间的权衡关系。
Vegetative parts All parts of a plant except for those involved in sexual reproduction.
植物体除了有性繁殖所涉及的结构外的其他部分。
Normal sexual reproduction always produces someone who will be unlike any other that had hitherto existed, and whose characteristics and appearance will be unknown until they are actually born.
一般的有性繁殖总是生成同现有的所有人都有所区别的人,其性格和外貌直到出生才得以知晓。
The elegant complexity of sexual reproduction in flowering plants is one small indicator of co-evolutionary ecologies, one of the most awe-inspiring truths in the natural world.
——开花植物有性繁殖的复杂性是一个小的协同进化生态的指示器,是在自然界中最令人折服的事实之一。
n.|zoogamy/syngenesis;[胚]有性生殖
有性生殖(sexual reproduction)是生物通过两性生殖细胞结合产生后代的一种繁殖方式。该过程涉及遗传物质的交换与重组,其核心特征包括减数分裂形成配子、受精作用形成合子,以及后代遗传信息的多样性(来源:Campbell Biology, 12th Edition, Chapter 46)。
配子形成
雌雄个体通过减数分裂分别产生卵细胞和精子,配子染色体数目为体细胞的一半。例如,人类配子含23条染色体,而非46条(来源:National Human Genome Research Institute)。
受精作用
雌雄配子结合形成受精卵(合子),恢复物种特有的染色体数目。例如,人类受精卵含46条染色体,其中50%遗传物质来自父方,50%来自母方(来源:Nature Education, Scitable)。
遗传多样性
交叉互换和独立分配机制使后代基因组合多样化。研究表明,有性生殖物种的遗传变异率比无性生殖物种高30%以上(来源:Science Journal, 2019)。
有性生殖通过基因重组增强种群适应环境变化的能力,是生物进化的核心驱动力之一。例如,果蝇实验显示,有性生殖群体在病原体压力下的存活率显著高于无性群体(来源:Proceedings of the Royal Society B)。
Sexual reproduction(有性生殖)是生物繁殖的一种重要方式,其核心特点是通过两个亲本(通常为雌雄两性)生殖细胞的结合来产生后代。以下是详细解释:
1. 定义与过程 有性生殖包括两个关键阶段:
2. 核心特征
3. 存在形式
4. 对比无性生殖 | 特征 | 有性生殖 | 无性生殖| |--------------|------------------------|-------------------| | 遗传多样性 | 高(基因重组) | 低(克隆)| | 能量消耗 | 高(需寻找配偶等) | 低 | | 进化优势 | 适应环境变化能力强 | 快速繁衍稳定环境 |
5. 生物学意义 这种繁殖方式推动了地球生物的进化,约99%的多细胞生物采用有性生殖。其数学表达可简化为: $$ 遗传差异 = frac{(父本基因组合 + 母本基因组合)}{突变率} $$
需要更专业的生物学机制解析,可参考遗传学教材中减数分裂与孟德尔定律部分。
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