
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.
這種接合對的出現可能與自接型有關,其有性過程可能是一種原始的有性生殖類型。
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種類型的生命周期,其劃分标準時生物體時期存在的階段。
Human beings propagate their species by sexual reproduction.
人類是通過有性生殖來繁衍同類的。
In clones, the genes are effectively tied together like beads on a string. There is no reshuffling as there is during sexual reproduction.
如果是無性繁殖的個體,其基因片段就像珠鍊一樣高效地系在一塊兒,不會象有性繁殖時那樣發生洗牌似的重組。
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.
并且具有一定的遺傳基礎,主要表現在蚜蟲體内酶系的變化、染色體變異、有性繁殖中同型交配行為及種群的遺傳分化上。
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.
這就解釋了性的重要性:在有性生殖過程中,染色體之間交換DNA比特,良性和惡性變體可以實現分離。
These species time their sexual reproduction with periods of environmental uncertainty, and reproduce asexually when conditions are more favourable.
這些物種按環境不确定的時期安排它們有性生殖的時間,當條件較為有利時它們進行無性繁殖。
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.
認為‘正午’牡丹有性生殖敗育的主要原因是不能形成足夠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産孢子,而這些孢子是可以被免疫系統輕易地識别并清除掉的。
To some extent, moderate and heavy grazing can enhance clonal growth ability of grasses, but depress sexual reproduction ability.
在種群水平上,中等強度以上的放牧幹擾有利于植物的克隆生長,但有性生殖減弱。
You always want the variation that's present in a natural population going on through sexual reproduction.
我們所希望得到的自然群體的遺傳變種一般是通過有性繁殖而産生的。
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.
告訴他們正确的生理知識和有性生殖,你可以在孩子四年級的時候開始向他們傳授。
The sexual reproduction plant has similar trends too.
有性繁殖植株也有相似的趨勢。
Bacteria are capable of sexual reproduction.
細菌可以進行有性繁殖。
Trade-off between clonal and sexual reproduction was not detected during the experimental research.
我們的實驗結果未發現克隆繁殖和有性繁殖之間的權衡關系。
Vegetative parts All parts of a plant except for those involved in sexual reproduction.
植物體除了有性繁殖所涉及的結構外的其他部分。
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.
一般的有性繁殖總是生成同現有的所有人都有所區别的人,其性格和外貌直到出生才得以知曉。
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.
——開花植物有性繁殖的複雜性是一個小的協同進化生态的指示器,是在自然界中最令人折服的事實之一。
n.|zoogamy/syngenesis;[胚]有性生殖
有性生殖(sexual reproduction)是生物通過兩性生殖細胞結合産生後代的一種繁殖方式。該過程涉及遺傳物質的交換與重組,其核心特征包括減數分裂形成配子、受精作用形成合子,以及後代遺傳信息的多樣性(來源:Campbell Biology, 12th Edition, Chapter 46)。
配子形成
雌雄個體通過減數分裂分别産生卵細胞和精子,配子染色體數目為體細胞的一半。例如,人類配子含23條染色體,而非46條(來源:National Human Genome Research Institute)。
受精作用
雌雄配子結合形成受精卵(合子),恢複物種特有的染色體數目。例如,人類受精卵含46條染色體,其中50%遺傳物質來自父方,50%來自母方(來源:Nature Education, Scitable)。
遺傳多樣性
交叉互換和獨立分配機制使後代基因組合多樣化。研究表明,有性生殖物種的遺傳變異率比無性生殖物種高30%以上(來源:Science Journal, 2019)。
有性生殖通過基因重組增強種群適應環境變化的能力,是生物進化的核心驅動力之一。例如,果蠅實驗顯示,有性生殖群體在病原體壓力下的存活率顯著高于無性群體(來源:Proceedings of the Royal Society B)。
Sexual reproduction(有性生殖)是生物繁殖的一種重要方式,其核心特點是通過兩個親本(通常為雌雄兩性)生殖細胞的結合來産生後代。以下是詳細解釋:
1. 定義與過程 有性生殖包括兩個關鍵階段:
2. 核心特征
3. 存在形式
4. 對比無性生殖 | 特征 | 有性生殖 | 無性生殖| |--------------|------------------------|-------------------| | 遺傳多樣性 | 高(基因重組) | 低(克隆)| | 能量消耗 | 高(需尋找配偶等) | 低 | | 進化優勢 | 適應環境變化能力強 | 快速繁衍穩定環境 |
5. 生物學意義 這種繁殖方式推動了地球生物的進化,約99%的多細胞生物采用有性生殖。其數學表達可簡化為: $$ 遺傳差異 = frac{(父本基因組合 + 母本基因組合)}{突變率} $$
需要更專業的生物學機制解析,可參考遺傳學教材中減數分裂與孟德爾定律部分。
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