作者: FISC 時(shí)間: 2025-3-21 21:28
The Diplohaplontic Life Cycleto-phyte phase; both phases are multicellular so somatic growth follows meiosis and somatic growth follows the union of gametes or syngamy. But even so, there are variants within this basic plan. Some angiosperm species, like bamboo, flower only once at the end of life. Conifers, by contrast, are lo作者: 該得 時(shí)間: 2025-3-22 03:25
Separate Female and Male Meiosesxtent, other conifers and gymnosperms. Meiosis is the process by which the chromosomal complement is reduced by half. The resulting haploid spores, male and female, develop into multicellular gametophytes. Male and female meioses are both followed by cell division and subsequent growth of multicellu作者: characteristic 時(shí)間: 2025-3-22 05:01
The Female Gametophyte Inside the Ovules develop integumented ovules (or megasporangia). Within each ovule‘s nucellar tissue forms sporogenous cells which give rise to a megaspore mother cell (MMC). The megaspore mother cell undergoes meiosis and the product of female meiosis is the linear tetrad of four megaspores. Only the megaspore cl作者: ticlopidine 時(shí)間: 2025-3-22 10:24
The Male Gametophyte Enclosed in a Pollen Walltral cone axis. Each sporophyll has microsporangia or pollen sacs attached to its underside. Each pollen sac contains many pollen mother cells (PMC) and each pollen mother cell undergoes meiosis then gives rise to four microspores after meiosis. Each microspore develops into a multicellular, mobile 作者: obtuse 時(shí)間: 2025-3-22 16:58
Pollination and Fertilizationesembles a stochastic process. During female strobilus receptivity, ovules exude a localized pollination drop at night. By early morning, the pollination drop retracts, pulling its captured grains inside the micropylar arms, closer to the spongy nucel-lus. Hydrated by the pollination drop, the polle作者: obtuse 時(shí)間: 2025-3-22 19:36 作者: 涂掉 時(shí)間: 2025-3-22 22:46
The Dynamic Wind-Pollinated Mating System pollen capture while minimizing selfing and interspecific hybridization. Aerodynamics of moving branches, leaves and female strobili favor pollen movement into ovules while more cryptic molecular mechanisms influence paternal parent choice from pollination onward to seed maturity. Outcrossing is th作者: 遠(yuǎn)足 時(shí)間: 2025-3-23 04:43 作者: 宣誓書(shū) 時(shí)間: 2025-3-23 08:53 作者: Pruritus 時(shí)間: 2025-3-23 10:59 作者: 不出名 時(shí)間: 2025-3-23 16:20 作者: amplitude 時(shí)間: 2025-3-23 20:20
Proton-Sugar Co-transporters in Plantsto-phyte phase; both phases are multicellular so somatic growth follows meiosis and somatic growth follows the union of gametes or syngamy. But even so, there are variants within this basic plan. Some angiosperm species, like bamboo, flower only once at the end of life. Conifers, by contrast, are lo作者: Exclude 時(shí)間: 2025-3-23 23:31 作者: SLING 時(shí)間: 2025-3-24 02:25 作者: Hearten 時(shí)間: 2025-3-24 09:28 作者: 施加 時(shí)間: 2025-3-24 14:25 作者: scotoma 時(shí)間: 2025-3-24 18:53 作者: 不可比擬 時(shí)間: 2025-3-24 21:09 作者: 裂口 時(shí)間: 2025-3-24 23:10
J. A. Mydosh,T. Endstra,G. J. Nieuwenhuyss incomplete so how are self-pollinated ovules or seeds selectively eliminated? Barriers to selfing have long been considered to be either competition via simple polyembryony and death to selfed embryos during seed maturation. Experimental results show that simple polyembrony is a weak barrier again作者: 排他 時(shí)間: 2025-3-25 03:35 作者: 歡笑 時(shí)間: 2025-3-25 07:53
http://image.papertrans.cn/c/image/235543.jpg作者: 老巫婆 時(shí)間: 2025-3-25 11:58 作者: 發(fā)起 時(shí)間: 2025-3-25 19:04
Proton-Sugar Co-transporters in Plantsrmined germline typical of the diplontic life cycle of vertebrates. This “moving interface” between vegetative and reproductive cell lineages has not been well-studied in conifers and it constitutes a fertile area for exploring adaptive response, mutational accumulation, DNA repair systems and regul作者: GNAW 時(shí)間: 2025-3-25 20:09
Possible Futures of Vehicle Safety,hromosomes. Meiosis I is characterized by few chiasmata per chromosome. Male and female meiosis in . spp. are divergent, occurring at different times and producing different tetrad types. Meiotic recombination rates are higher in male gametes than female gametes. An consequence of heterospory, or se作者: entitle 時(shí)間: 2025-3-26 01:06 作者: occurrence 時(shí)間: 2025-3-26 07:06 作者: IST 時(shí)間: 2025-3-26 11:08 作者: LEERY 時(shí)間: 2025-3-26 14:51
Textbook 2009r- tion of generations in conifers shows strong divergence in the evolution of male and female gametes, as well as in the synchronicity of male and female gamete development. How are these coordinated to achieve fertilization? Books on conifer reproduction are all too rare. The only major work in th作者: Dendritic-Cells 時(shí)間: 2025-3-26 20:16
Introducing Conifersemi pine are critically endangered. Vestiges of the ancient conifer diaspora can be seen in the fossilized .-dominated forests in Canadian High Arctic and from the endemic Da Lat ecosystem in Vietnam which includes the flat-leaved .. Conifers are among the oldest extant seed plant lineage and their 作者: 禁止,切斷 時(shí)間: 2025-3-27 00:44
The Diplohaplontic Life Cyclermined germline typical of the diplontic life cycle of vertebrates. This “moving interface” between vegetative and reproductive cell lineages has not been well-studied in conifers and it constitutes a fertile area for exploring adaptive response, mutational accumulation, DNA repair systems and regul作者: GREEN 時(shí)間: 2025-3-27 03:16 作者: 整潔漂亮 時(shí)間: 2025-3-27 07:44 作者: 鞠躬 時(shí)間: 2025-3-27 11:13 作者: Coeval 時(shí)間: 2025-3-27 15:03
The Embryo Lethal Systemed to infer severity and distribution of lethal factors; to date, most are semi- lethal rather than fully lethal. These range from partially dominant to overdominant or perhaps balanced lethals..Some selfed embryos die at all stages of seed development but a second death pattern has been detected in作者: 粗糙濫制 時(shí)間: 2025-3-27 19:16
male gametes, as well as in the synchronicity of male and female gamete development. How are these coordinated to achieve fertilization? Books on conifer reproduction are all too rare. The only major work in th978-90-481-8167-4978-1-4020-9602-0作者: depreciate 時(shí)間: 2025-3-27 22:12 作者: expository 時(shí)間: 2025-3-28 02:15 作者: 殺人 時(shí)間: 2025-3-28 10:18
value of conifers is significant.Includes supplementary matWhen it comes to reproduction, gymnosperms are deeply weird. Cycads and co- fers have drawn out reproduction: at least 13 genera take over a year from polli- tion to fertilization. Since they don’t apparently have any selection mechanism by作者: conscience 時(shí)間: 2025-3-28 11:33
Textbook 2009 polli- tion to fertilization. Since they don’t apparently have any selection mechanism by which to discriminate among pollen tubes prior to fertilization, it is natural to w- der why such a delay in reproduction is necessary. Claire Williams’ book celebrates such oddities of conifer reproduction. S
