
Chromosome number | Definition, Haploid, & Diploid | Britannica
2025年3月1日 · In sexually reproducing organisms, the number of chromosomes in the body (somatic) cells typically is diploid (2n; a pair of each chromosome), twice the haploid (1n) number found in the sex cells, or gametes. The haploid number is produced during meiosis.
Evolutionary Dynamics of Unreduced Gametes - ScienceDirect
2017年9月1日 · To better understand this discrepancy, we review contemporary evidence related to four aspects of 2n gamete dynamics in natural populations: (i) estimates of their frequency; (ii) their environmental and genetic determinants; (iii) adaptive and nonadaptive processes regulating their evolution; and (iv) factors regulating their union and ...
Two pathways of 2n gamete formation and differences in the …
2022年8月19日 · The Epidendrum is unique in that it forms 2n pollens via two pathways, namely, meiotic defects and pre-meiotic chromosome doubling. These two pathways of 2n pollen formation could influence the high diversity generation of polyploidy with different degrees of heterozygosity and genetic backgrounds in the genus Epidendrum.
Evolutionary Dynamics of Unreduced Gametes: Trends in Genetics …
2017年7月18日 · Unreduced gametes, which have the somatic (2n) chromosome number, are an important precursor to polyploid formation and apomixis. The product of irregularities in meiosis, 2n gametes are expected to be rare and deleterious in most natural populations, contrary to their wide taxonomic distribution and the prevalence of polyploidy.
The role of 2n gametes and endosperm balance number in the …
In this article we outline the unique characteristics of 2n gametes and implications of their participation in the evolution of polyploid Solanum species. The genetic consequences of 2n gametes indicate that sexual polyploidization results in greater variability, fitness, and heterozygosity than does somatic doubling.
Genomics-based discrimination of 2n gamete formation …
In this study, we propose a genotyping-based strategy to uncover the mechanisms of 2n gamete formation in progeny that has a higher ploidy than its parents. Simulation of 2n gamete production revealed that FDR and SDR pathways can be discriminated based on allele transmission patterns alone without information on centromere location.
Genetic: The loss of genetic heterozygosity. This is normally associated with chromosomal reduction, but can also result from crossing over during 2n gamete formation: The term "unreduced gamete" is frequently abused by using it incorrectly to refer to 2n gametes in general.
Role of 2n Gametes and Endosperm Balance Number in the Origin …
2003年1月1日 · In this article we outline the unique characteristics of 2 n gametes and implications of their participation in the evolution of polyploid Solanum species. The genetic consequences of 2 n gametes indicate that sexual polyploidization results in greater variability, fitness, and heterozygosity than does somatic doubling.
Genomics-based discrimination of 2n gamete formation ... - PubMed
2021年8月7日 · In this study, we propose a genotyping-based strategy to uncover the mechanisms of 2n gamete formation in progeny that has a higher ploidy than its parents. Simulation of 2n gamete production revealed that FDR and SDR pathways can be discriminated based on allele transmission patterns alone without information on centromere location.
植物2n配子发生及其遗传标记研究进展 - chinagene.cn
摘要: 文章综述了植物2n配子发生及其遗传标记研究现状,论述涉及有关形态学标记、细胞学标记、同工酶标记乃至DNA标记等遗传标记在2n配子研究中的应用,指出通过花粉形态观察、大小孢子母细胞减数分裂行为观察、杂种后代倍性鉴定以及亲子分子标记相关 ...