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  • 植物生殖和生命周期

    A bee pollinating a white flowering plant, emphasizing plant reproduction.

    Fertilization or pollination. How does this occur in the plant?
    ::肥料化或授粉。这在工厂中是如何发生的?

    Pollination . A significant step in the of flowering plants. But must occur in the life cycles of all plants, not just those with flowers . Does it always use the or the bees?
    ::授粉。 开花植物中的重要一步。 但必须发生在所有植物的生命周期中, 不仅仅是那些有花的植物。 它总是使用蜜蜂还是使用蜜蜂?

    General Plant Life Cycle
    ::普通植物生命周期

    The life cycle of all plants is complex because it is characterized by alternation of generations . Plants alternate between diploid sporophyte and haploid gametophyte generations, and between sexual and . The ability to reproduce both sexually and asexually gives plants the flexibility to adapt to changing environments. Their complex life cycle allows for great variation. A general plant life cycle is represented by the diagram in Figure . From the figure, you can see that the diploid sporophyte has a structure called a sporangium (plural, sporangia) that undergoes to form haploid spores . A spore develops into a haploid gametophyte . The gametophyte has male or female reproductive organs that undergo to form haploid gametes ( or eggs). Fertilization of gametes produces a diploid zygote . The zygote grows and develops into a mature sporophyte, and the cycle repeats.
    ::所有植物的生命周期都非常复杂,因为其特点是代代相传。 植物在潮湿的植物和辣椒的游戏植物代代之间以及性与 。 性与性繁殖的能力使植物具有适应变化环境的灵活性。 它们复杂的生命周期允许巨大的变化。 图中的图表代表了整个植物生命周期。 从图中可以看出, 潮湿的植物有一个结构, 叫做( 花生、 花生) , 形成杂交的螺旋。 花生植物发展成一个杂交的游戏植物。 游戏的植物有男性和女性生殖器官, 形成杂交的游戏( 或卵 ) 。 游戏的肥化产生一个调味的zygote。 zygote 生长并发展成一个成熟的螺旋, 循环重复 。

    The plant life cycle with sporophyte, gametophyte, and reproductive processes.

    This diagram represents the life cycle that generally characterizes plants.
    ::该图代表了通常作为植物特征的生命周期。

    One of the two generations of a plant’s life cycle is typically dominant to the other generation. Whether it’s the sporophyte or gametophyte generation, individuals in the dominant generation live longer and grow larger. They are the green, photosynthetic structures that you would recognize as a , tree, or other plant (see Figure ). Individuals in the nondominant generation, in contrast, may be very small and rarely seen. They may live in or on the dominant plant.
    ::植物生命周期的两代人中,有一代人通常在另一代人中占据主导地位。 不管是花生还是草药一代,占支配地位的一代人活得更长,长大也更大。 它们是绿色的、光合结构,你们会承认它们为植物、树木或其他植物(见图 ) 。 相反,非占支配地位的一代人可能非常小,很少被看到。 他们可能生活在占支配地位的植物中,也可能生活在占优势的植物中。

    The dominant generation in is the gametophyte; in , it’s the sporophyte. Why is a dominant sporophyte generation an advantage on land?
    ::占主导地位的一代是游戏植物;而它的代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代代言。

    Four plant types showing dominant life cycle generations: moss (gametophyte), fern, pine, apple (all sporophytes).

    All of these photos show plants of the dominant generation in their life cycle.
    ::所有这些照片都显示 占优势的一代的植物 在其生命周期。

       

     

    Summary
    ::摘要

    • All plants have a life cycle with alternation of generations.
      ::所有植物都有生命周期 代代相传
    • Plants alternate between diploid sporophyte and haploid gametophyte generations, and between sexual reproduction with gametes and asexual reproduction with spores.
      ::各种植物交替生长于低脂植物和低脂的游戏植物代际之间,以及性生殖与调子和性生殖与种子之间的交替生长。

    Review
    ::回顾

    1. Outline the general life cycle of plants.
      ::概述植物的一般生命周期。
    2. What are sporangia? What do they do?
      ::什么是幻死,他们做什么?
    3. Describe the gametophyte.
      ::描述游戏植物。
    4. Describe the sporophyte.
      ::描述血吸附物。