Fields such as behavioural and evolutionary ecology are built on the assumption that natural selection leads to organisms that behave as if they are trying to maximise their fitness. However, there is considerable evidence for selfish genetic elements th
Lampreys are sometimes said to pass through an initial female stage or female intersexual stage, because mitosis and meiosis appear to occur in most larvae regardless of future sex. However, meiosis and oocyte growth are more synchronized and extensive in female larvae, and the extent to which ...
Immediately after polyploidization, nascent polyploid must pass through a bottleneck of genomic disruption5,47, including changes in cellular architecture, difficulties in meiosis, regulatory changes of gene expression, and alteration of epigenetic landscapes, before becoming adapted and fueling long-term ...
Which of the following is the lining of the uterus most associated with the menses? a. cervix b. myometrium c. fallopian tubes d. endometrium The Menstrual Cycle: When a young woman reaches puberty her menstrual cycle begins. The...
At the heart of meiosis is crossover recombination, i.e., reciprocal exchange of chromosome fragments between parental genomes. Surprisingly, in most eukar
In the presence of horizontal gene transfer (HGT), the concepts of lineage and genealogy in the microbial world become more ambiguous because chimeric genomes trace their ancestry from a myriad of sources, both living and extinct. We present the evolutio
As male diploid germ cells resume meiosis only shortly before puberty, there probably is a need to tolerate gamete-expressed antigens that have not been presented at birth. So, to limit immune-mediated damage, systemic immune responses in this compartment are kept in check by the blood-testis ...
Itisthiseventthatresultsinthehalvingofthechromosomenumberinthefourdaughtercellsthatresultfrommeiosis.象有丝决裂那样,在分裂前I期的开始,每个染色体含有两条染色单体。在这一阶段,两个同源染色单体通过蛋白质和 RNA桥配对产生联会复合体。当同源染色体对布列于赤道板上时,这两条染色体同时存在。然而,与有丝决裂后期不...
This has led to the development of several large-scale methodologies that are grouped together under the term functional genomics/proteomics, with the aim of investigating the putative gene functions [1–3]. In the context of functional genomics, yeast Saccharomyces cerevisiae has emerged as the ...
This threshold value of δ is especially relevant since, when drive is limited to the meiosis of one sex (as it usually is), the value of δ for the species, averaged across the two sexes, is necessarily ≤1/2. Taking into account the relative numbers of linked and unlinked loci, Eqs...