章节大纲

  • 常规

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  • 非血管植物

    An illustration of ancient forests with nonvascular and seedless vascular plants, depicting lush vegetation.

    What did forests look like millions of years ago?
    ::几百万年前的森林是什么样子的?

    The trees you see today did not exist. Nonvascular plants and vascular seedless plants first dominated the forest. The remains of these forests formed the coal that we depend on today.
    ::今天你看到的树木并不存在。非血管植物和无血管种子植物首先占据了森林。这些森林的残骸形成了我们今天赖以生存的煤炭。

    Nonvascular Seedless Plants
    ::非大气无种子植物

    Nonvascular seedless plants , as their name implies, lack vascular tissue . Vascular tissue is specialized tissue that transports water, nutrients , and food in plants. As they lack vascular tissue, they also do not have true roots , stems , or leaves. Nonvascular plants do often have a “leafy” appearance, though, and they can have stem-like and root-like structures. These plants are very short because they cannot move nutrients and water up a stem.
    ::无血管种子植物,如其名称所暗示的那样,缺乏血管组织。血管组织是专门组织,在植物中输送水、养分和食物。由于它们缺乏血管组织,它们也没有真正的根、根或叶。但非血管植物的外观往往“疏松 ” , 可以有干状和根状的结构。这些植物非常短,因为它们不能将养分和水移到干干上。

    Nonvascular seedless plants, also known as bryophytes , are classified into three phyla:
    ::无血管种子植物,又称血眼植物,分为三种植物:

    1. Mosses
      ::蚊子
    2. Hornworts
      ::黄蜂
    3. Liverworts
      ::肝脏

    Mosses
    ::蚊子

    Mosses are most often recognized as the green “fuzz” on damp rocks and trees in a forest. If you look closely, you will see that most mosses have tiny stem-like and leaf-like structures. This is the gametophyte stage. Remember that a gametophyte is haploid , having only one set of chromosomes . The gametophyte produces the gametes that, after , develop into the diploid sporophyte with two sets of chromosomes. The sporophyte forms a capsule , called the sporangium , which releases spores ( Figure ).
    ::蚊子通常被公认为森林中潮湿岩石和树木上的绿色“ 模糊” 。 如果你仔细看一看, 就会发现大多数苔类都有细小的干类和叶类结构。 这就是游戏植物阶段。 这是游戏植物的舞台。 记住, 游戏植物是杂交, 只有一个染色体。 游戏植物产生调子, 之后, 形成两组染色体。 浮质形成一个胶囊, 叫做, 释放螺旋( Figure ) 。

    Moss displaying gametophyte with sporophytes growing on stalks above it.

    Sporophytes sprout up on stalks from this bed of moss gametophytes. Notice that both the sporophytes and gametophytes exist at the same time.
    ::Sporophites从这张摩斯的草本植物床的树轨上浮现出来。 请注意, 浮质和草本植物同时存在 。

    Hornworts
    ::黄蜂

    Hornworts are named for their appearance. The "horn" part of the name comes from their hornlike sporophytes, and “wort” comes from the Anglo-Saxon word for herb. The hornlike sporophytes grow from a base of flattened lobes, which are the gametophytes ( Figure ). They usually grow in moist and humid areas.
    ::霍恩沃特因它们的外观而命名。 名字中的“ 角”部分来自角状的,而“ 角”则来自盎格鲁-撒克逊语的草药。 角状的从扁状的叶子的基底生长,这些叶子是游戏植物(图 ) 。 它们通常生长在潮湿和潮湿地区。

    Hornworts with hornlike sporophytes emerging from a base of flattened, leaflike gametophytes.

    In hornworts, the “horns” are the sporophytes that rise up from the leaflike gametophyte.
    ::在黄蜂中,“喇叭”是从叶状的游戏植物中上升的。

    Liverworts
    ::肝脏

    Liverworts have two distinct appearances: they can either be leafy like mosses or flattened and ribbon-like. Liverworts get their name from the type with the flattened bodies, which can resemble a liver ( Figure ). Liverworts can often be found along stream beds.
    ::肝脏有两种不同的外观:它们可以像苔丝一样叶状,也可以是扁平的,也可以像丝带一样。 肝脏和扁平的躯体有相似的肝脏(图 ) 。 肝脏通常可以在溪流的床边找到。

    Close-up of thallose liverworts with flattened, ribbon-like green bodies.

    Liverworts with a flattened, ribbon-like body are called thallose liverworts.
    ::长着扁平的、像丝带一样身体的肝脏结,被称为硫柳叶肝结。

    Summary
    ::摘要

    • Nonvascular plants lack seeds and vascular tissue.
      ::非血管植物缺乏种子和血管组织。
    • Nonvascular plants include the mosses, the hornworts, and the liverworts.
      ::非血管植物包括苔胱、角状和肝脏。

    Explore More
    ::探索更多

    Use the resource below to answer the questions that follow.
    ::利用以下资源回答以下问题。

    • Nonvascular Plants at (3:22)
      ::3:22时(3:22)的无血管植物
    1. How do bryophytes keep their eggs from drying out?
      ::血友病如何防止卵干?
    2. How does bryophyte sperm locate the bryophyte egg?
      ::白眼精子如何定位白眼蛋?
    3. What happens in the archegonia?
      ::在大主教区发生什么了?
    4. What happens in the antheridium?
      ::里会发生什么事?
    5. Where does fertilization of the bryophyte egg occur?
      ::血友病蛋的施肥在哪里发生?

    Review
    ::回顾

    1. What is a bryophyte?
      ::什么是恋童癖?
    2. What are examples of nonvascular plants?
      ::非血管植物的例子是什么?
    3. Why do nonvascular plants tend to be very short?
      ::为什么非血管植物往往很短?