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植物生理学英文翻译

植物生理学英文翻译


中文翻译: 中文翻译:
?腋生分生组织 腋生分生组织在叶腋处形成,来源于嫩芽顶端分生组织。它能生长发育成 腋生分生组织 植物体主轴上的枝条。 ?居间分生组织 居间分生组织通常生长在植物体器官的基部。植物体被伤害或被啃食后, 居间分生组织 植物体茎间的居间分生组织会使植株继续生长。 ?侧根分生组织 侧根分生组织具有初级分生组织的结构,但是它们是由成熟器官基部的中 侧根分生组织 柱鞘细胞形成的。不定根也能从居间分生组织分化产生并发育成茎,如扦插繁殖 的植物体的根。 ?维管形成层 维管形成层(复数形成层)是一种次生分生组织,它区别于前形成层内的 维管形成层 维管柱的初级维管组织。 它并不分化为横向器官, 而只分化成茎和根的木质组织。 维管形成层包含两种类型的分生细胞:纺锤状原始细胞和射线原始细胞。纺锤状 原始细胞高度伸长,其中的空泡细胞纵向分裂再生形成自身,并且其衍生物分化 成次生木质部和韧皮部的疏导细胞。射线原始细胞是一种小细胞,它的衍生物包 括径向导向的薄壁组织细胞,组成维管射线。 ?木塞形成层 木塞形成层是一种分生组织, 它可以发育成表皮的成熟细胞和次生韧皮部。 木塞形成层 木塞形成层的衍生物有多种,如可发育成具有保护作用的周皮或树皮。周皮形成 次生植物体外部保护层,而不是木质部和根部的表皮。 腋生、 腋生、花以及花序分生组织是由植物分生组织分化而来 一些不同类型的幼芽的分生组织可以根据它们所发育成的器官, 所形成的侧 生器官以及是否是有限的 有限的(有一个基因编程限制它们的生长)或无限的 无限的(没有特 有限的 无限的 定的生长限制,只要环境满足需要便可生长)。 植物的嫩芽顶端分生组织的生长通常是无限的。 只要环境条件满足其生长的 需要,它就会不断的形成植物体的生长节点,而不产生开花刺激。一个生长节点 生长节点 是组成一个或多个叶片或腋芽的发展单位,该节点与叶片相连,节间部在节点下 方(图 16.14)。腋芽 腋芽是一种次生分生组织,如果它们也是植物分生组织,它们 腋芽 将会有类似于顶端分生组织的结构以及发育潜能。 在植物体开花诱导中, 植物分生组织可直接转化为花分生组织 (见第 24 章) 。 花分生组织不同于植物分生组织,它们可以代替叶片发育成花的器官:萼片、花 花分生组织

瓣、雄蕊和心皮。另外,花分生组织是被限定的:在最后的花器官形成后,所有 分生组织的活动都会停止。 在许多情况下,植物体分生组织是不能直接转化为花分生组织的。相反,植 物分生组织是先转化为花序分生组织 由花序分生组织所产生的侧生器官与花分 花序分生组织。 花序分生组织 生组织所产生的是不同的。花序分生组织产生的苞片,花分生组织在叶腋处形成 苞片,而不是萼片、花瓣、雄蕊和胚珠,这些是由花分生组织产生的。花序分生 组织的确定与不确定取决于物种的种类。 叶的发育 大多数植物的叶片是光合作用的器官。在叶片中,光能被捕获,并用于驱动 植物体生命活动中重要的化学反应。 虽然物种与物种之间的叶子的大小与形状不 同,但是一般来说,叶片都是薄而扁平的结构,并有背腹之分。这种外形与嫩芽 顶端分生组织和枝条相比,叶片两边呈径向对称。另一个重要的区别是叶原基有 特定的长度,而植物嫩芽顶端分生组织是不定的。接下来的几章都有对叶片在不 同阶段的发育的描述(Sinha 1999)。 阶段一: 器官的形成。 嫩芽顶端分生组织的顶端第一层和第二层的少量细胞 阶段一: 器官的形成。 具有叶原基的特性。这些细胞分裂的速度大于周围细胞,产生代表叶原基的副产 物(复数原基)(图 16.15A)。这些叶原基随后生长和发育成叶片。 阶段二:子器官域的发育。 阶段二:子器官域的发育。不同区域的原基需要叶片特定区域的识别。这种 分化是沿三轴:背腹面 背腹面(远轴端-近轴端)、靠近远轴端 靠近远轴端(顶点-基部) 侧面 和侧面 侧面(边 背腹面 靠近远轴端 缘-叶片-中脉)(图 16.15B)。上(正面)表面的叶片是专司吸收光的;下(背 面)表面是专司气体交换的。叶片的结构和成熟度也沿远轴端和侧面方向分布。 阶段三:细胞和组织的分化。 阶段三:细胞和组织的分化。随着发育中的叶片的生长,叶片的细胞和组织 也在分化。来源于第一层细胞分化成表皮(表皮细胞、表皮毛、保卫细胞),第 二层细胞的衍生物分化成光合叶肉细胞,维管原件和维管束鞘细胞来源于第三 层。这些细胞的分化型是一个由基因决定的特征,但在某种程度上,物种修饰反 应环境。 叶原基的位置是由基因编程的 叶原基形成的时机和形状是先天决定的,通常是一个物种的特征。叶原基的 数量和排列顺序反映在叶片在茎部的分布,称为叶序 叶序(图 16.16)。叶序主要有 叶序

五种类型: 1. 互生叶序 互生叶序。每个节点上只有一个单一的叶片(图 16.16A)。 2. 对生叶序 对生叶序。叶片在枝条的两边对立生长(图 16.16B) 3. 交互对生叶序 交互对生叶序。在植物发育过程中,每个节点上的叶片成对排列,相邻 各对叶片之间并成直角排列(图 16.16C)。 4. 轮生叶序 轮生叶序。每个叶片上产生 2 片以上的叶片(图 16.16D)。 5. 螺旋叶序 螺旋叶序。互生叶序的一种,叶片成一定的角度生长,使叶片环茎螺旋 排列(图 16.16E)。 叶原基的位置一定是由顶端确定的空间生长。 我们对于叶原基位置的调整以 及叶原基形成的信号了解的很少。 一种说法认为已形成的叶原基的抑制区影响下 一个叶原基的间隔距离。

Englishi control: :
?Axillary meristems are formed in the axils of leaves and are derived from the shoot apical meristem.The growth and development of axillary meristems produces branches from the main axis of the plant. ?Intercalary meristems are found within organs, often near their bases. The intercalary meristems of grass leaves and stems enables them to continue to grow despite mowing or grazing by cows. ?Branch root meristems have the structure of the primary root meristem, but they form from pericycle cells in mature regions of the root. Adventitious roots also can be produced from lateral root meristems that develop on stems, as when stem cuttings are rooted to propagate a plant. ?The vascular cambium (plural cambia) is a secondary meristem that differentiates along with theprimary vascular tissue from the procambium within the vascular cylinder. It does not produce lateral organs, but only the woody tissues of stems and roots. The vascular cambium contains two types of meristematic cells: fusiform stem cells and ray stem cells. Fusiform stem cells are highly elongated, vacuolate cells that divide longitudinally to regenerate themselves, and whose derivatives differentiate into the conducting cells of the secondary xylem and phloem. Ray stem cells are small cells whose derivatives include the radially oriented files of parenchyma cells within wood known as rays. ?The cork cambium is a meristematic layer that develops within mature cells of the cortex and the secondary phloem. Derivatives of the cork cambium differentiate as cork cells that make up a protective layer called the periderm, or bark. The periderm forms the protective outer surface of the secondary plant body, replacing the epidermis in woody stems and roots. Axillary, Floral, and Inflorescence Shoot Meristems Are Variants of the Vegetative Meristem Several different types of shoot meristems can be distinguished on the basis of their

developmental origin, the types of lateral organs they generate, and whether they are determinate (having a genetically programmed limit to their growth) or indeterminate (showing no

predetermined limit to growth; growth continues so long as resources permit). The vegetative shoot apical meristem usually is indeterminate in its development. It repetitively forms phytomeres as long as environmental conditions favor growth but do not generate a flowering stimulus. A phytomere is a developmental unit consisting of one or more leaves, the node to which the leaves are attached, the internode below the node, and one or more axillary buds (Figure 16.14).Axillary buds are secondary meristems; if they are also vegetative meristems, they will have a structure and developmental potential similar to that of the apical meristem. Vegetative meristems may be converted directly into floral meristems when the plant is induced to flower (see Chapter 24). Floral meristems differ from vegetative meristems in that instead of leaves they produce floral organs:sepals, petals, stamens, and carpels. In addition, floral meristems are determinate: All meristematic activity stops after the last floral organs are produced. In many cases, vegetative meristems are not directly converted to floral meristems. Instead, the vegetative meristem is first transformed into an inflorescence meristem. The types of lateral organs produced by an inflorescence meristem are different from the types produced by a floral meristem. The inflorescence meristem produces bracts and floral meristems in the axils of the bracts, instead of the sepals, petals, stamens, and ovules produced by floral meristems. Inflorescence meristems may be determinate or indeterminate, depending on the species. LEAF DEVELOPMENT The leaves of most plants are the organs of photosynthesis.This is where light energy is captured and used to drive the chemical reactions that are vital to the life of the plant.Although highly variable in size and shape from species to species, in general leaves are thin, flat structures with dorsiventral polarity. This pattern contrasts with that of the shoot apical meristem and stem, both of which have radial symmetry. Another important difference is that leaf primordia exhibit determinate growth, while the vegetative shoot apical meristem is indeterminate. As described in

the sections that follow, several distinct stages can be recognized in leaf development (Sinha 1999). Stage 1: Organogenesis. A small number of cells in the L1 and L2 layers in the flanks of the apical dome of the shoot apical meristem acquire the leaf founder cell identity.These cells divide more rapidly than surrounding cells and produce the outgrowth that represents the leaf primordium (plural develop into leaves. Stage 2: Development of sub organ domains. Different regions of the primordium acquire identity as specific parts of the leaf. This differentiation occurs along three axes: dorsiventral (abaxial–adaxial), proximodistal (apical–basal),and lateral (margin–blade–midrib) (Figure 16.15B). The upper (adaxial) side of the leaf is specialized for light absorption; the lower (abaxial) surface is specialized for gas exchange. Leaf structure and maturation rates also vary along the proximodistal and lateral axes. Stage 3: Cell and tissue differentiation. As the developing leaf grows, tissues and cells differentiate. Cells derived from the L1 layer differentiate as epidermis (epidermal cells, trichomes, and guard cells), derivatives of the L2 layer differentiate as the photosynthetic mesophyll cells, and vascular elements and bundle sheath cells are derived from the L3 layer. These cells differentiate in a genetically determined pattern that is characteristic of the species but to some degree modified in response to the environment. The Arrangement of Leaf Primordia Is Genetically Programmed The timing and pattern with which the primordia form is genetically determined and usually is a characteristic of the species. The number and order in which leaf primordial form is reflected in the subsequent arrangement of leaves around the stem, known as 16.16).There are five main types of phyllotaxy: 1. Alternate phyllotaxy. A single leaf is initiated at each node (see Figure 16.16A). 2. Opposite phyllotaxy. Leaves are formed in pairs on opposite side of the stem (see Figure 16.16B). phyllotaxy (Figure primordia) (Figure 16.15A). These primordia subsequently grow and

3. Decussate phyllotaxy. Leaves are initiated in a pattern with two opposite leaves per node and with successive leaf pairs oriented at right angles to each other during vegetative development (see Figure 16.16C). 4. Whorled phyllotaxy. More than two leaves arise at each node (see Figure 16.16D). 5. Spiral phyllotaxy. A type of alternate phyllotaxy in which each leaf is initiated at a defined angle to the previous leaf, resulting in a spiral arrangement of leaves around the stem (see Figure 16.16E). The positioning of leaf primordia must result from the precise spatial regulation of growth within the apex. We know little about how this positioning is regulated, or about the signals that initiate the formation of a primordium. One idea is that inhibitory fields generated by existing primordia influence the spacing of the next primordium.

Liaoning Normal University

植物生理学课程作业

题 学 年 学

目: 植物生理学英文翻译 生命科学学院 院: 生命科学学院 级: 2009 级 号: 20091132010053

学生姓名: 学生姓名: 张亚菲

2011 年 11 月


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