茎的结构

Secondly, according to the stem and leaf anatomy, leaf epidermis, pollen morphology and floral development, it is found that there are no close relations between Acorus and Typhales, especially in the aspect of floral development. In the course of floral development of A. calamus, neither bracteloe primordium nor common primordium occurs in the whole course. Early development of the flower is strongly unidirectional. Three shield carpels develop into a pistil. In Sparganium fallax, each female flower has a bracteole. The bracteole primordium and the floral primordium originate from a complex structure. A single saccate carpel develops into a pistil. In staminate flowers, petal and stamen primordia initiate spirally.

菖蒲属与香蒲目的茎叶解剖特征、叶表皮特征、花粉特征及花器官发生特点等亦存在着明显区别，特别是花器官发生特点差异尤为显著，如菖蒲属花器官发生过程中，没有苞片原基，也不存在任何形式的复合原基，花被与雄蕊原基均以单向性方式发生，雌蕊由3心皮发育而成，具有"盾状心皮"的特点等，黑三棱属则有苞片原基发生，且苞片原基与雌花原基起源于共同的复合结构，雄花的花被原基和雄蕊原基均以螺旋状方式发生，雌蕊由单心皮发育而成，未发现有2或3个心皮原基或其痕迹的现象，体现出"囊状心皮"的特点。

From the point of view of geobotany, with the method of correlative factors of growth of plants, a countrywide theoretic ecological division was done for the introduction of Camptotheca acuminata and three kinds of areas of ecological preferent zone, ecological adaptive zone and ecological unadaptable zone were divided. With the theory of synecology, the characteristic on environment, constitution, life form spectrum, diversity, similarity of plots of communities were researched. Applying the method of species association, discrete distribution, indensity index, fractal geometry, etc. to research relations between the species of the communities, space distribution of Camptotheca acuminata, structure of age of Camptotheca acuminata, in different communities. Using the theories of autoecology, distibutons of seeds on land and growth of seedlings in vertical and horizontal directions, biomass of organ of Camptotheca acuminata were analyzed. On the opinions of conservation biology, the external and internal factors impressing Camptotheca acuminata were analyzed to research the mechanism of the endangered species, and with using of CTM Model, the future development direction of Camptotheca acuminata in different communities were forecasted, and. Standing on the position of resources ecology, discussing the regularity of camptothein in Camptotheca acuminata of different sites and seeding of different resources, also the the derive technics of camptothecin.

本文从地植物学的角度，运用植物生长相关因子法，对我国喜树资源的生态适宜区进行了划分，理论上确定了我国的喜树的引种栽培的最适生活区域、生态适宜区域和不适宜生活区域；从群落生态学的角度，对野生喜树所在的典型群落的群落环境、群落组成、群落生活型谱、群落的物种多样性特点、群落样地间相似性进行了研究；从种群生态学的角度，运用种间联结性、离散分布模型、聚集强度指数、分析几何等分析手段，对野生喜树所在典型群落间的种间关系、喜树的空间分布格局、年龄结构等进行了分析；从个体生态学的角度，对不同年龄组的喜树的种子的散落的垂直分布、水平分布、时间分布及种子发芽率和千里重等特点、不同种源的人工喜树苗期特点、喜树的高生长和茎生长特点、喜树的器官生物量特点进行了研究；从保护生物学的角度，对野生喜树的濒危的内部因素和外部因素进行了探讨，并运用CTM模型对不同群落中野生喜树的种群趋势进行了预测；从资源生态学的角度，对我国地理环境下喜树中喜树碱含量的地理分布规律、不同种源的喜树幼苗中喜树碱含量变化规律进行了研究，并对喜树碱的提取工艺进行了探讨。

Three-dimensional morphological structures of leaf,stem,tasse...

其中，玉米叶片、茎节、雄穗、雌穗和根系的三维形态是由基于器官形态结构主要特征而构建的参数化的几何模型来描述的。

Thorn A stiff sharply pointed woody process that may be found on the stems of vascular plants.

棘的刺：维管植物茎杆上可见的一种坚硬的具锋利尖端的木质结构。

In cross-sectioned root form 2 middle bark layer next Internal bark layer especial structure of regularly array; epidermis cell of stems and leaves have developed thickened epiderm, leaves epidermis covers hair, it formed developed vascular bundles.(4)Chromosomes of Agropyron cristatum is tetraploid .

根横切面上形成了在紧靠内皮层的两层中皮层细胞有规则整齐排列成两环的特殊结构；茎和叶表皮细胞均具有发达的角质层，叶表皮多密被毛，其形成了发达的维管束及维管束鞘。

On the other side, the relations among community classification, structure, diversity and distribution pattern were also investigated through the study of species composition, diversity and interspecific relation of Medicago falcata in Inner Mongolia.

另一方面，本文又以松嫩平原天然草地中的五脉山黎豆、多茎野豌豆、花苜蓿以及内蒙古的黄花苜蓿为研究对象，从植物群落的物种组成、多样性、种间关联等几方面探讨了我国天然草地中豆科牧草的群落类型、结构、群落多样性与分布格局之间的关系。

Secondly, according to the stem and leaf anatomy, leaf epidermis, pollen morphology and floral development, it is found that there are no close relations between Acorus and Typhales, especially in the aspect of floral development. In the course of floral development of A. calamus, neither bracteloe primordium nor common primordium occurs in the whole course. Early development of the flower is strongly unidirectional. Three shield carpels develop into a pistil. In Sparganium fallax, each female flower has a bracteole. The bracteole primordium and the floral primordium originate from a complex structure. A single saccate carpel develops into a pistil. In staminate flowers, petal and stamen primordia initiate spirally.

菖蒲属与香蒲目的茎叶解剖特征、叶表皮特征、花粉特征及花器官发生特点等亦存在着明显区别，特别是花器官发生特点差异尤为显著，如菖蒲属花器官发生过程中，没有苞片原基，也不存在任何形式的复合原基，花被与雄蕊原基均以单向性方式发生，雌蕊由3心皮发育而成，具有&盾状心皮&的特点等，黑三棱属则有苞片原基发生，且苞片原基与雌花原基起源于共同的复合结构，雄花的花被原基和雄蕊原基均以螺旋状方式发生，雌蕊由单心皮发育而成，未发现有2或3个心皮原基或其痕迹的现象，体现出&囊状心皮&的特点。

The entire Superstructure cross-section, except for traffic barrier, shall be considered to be placed at one time for purposes of determining support requirements and designing falsework girders for their stresses and deflections, except as follows: For concrete box girder bridges, the girder stems, diaphrams, crossbeams, and connected bottom slabs, if the stem wall is placed more than 5 days prior to the top slab, may be considered to be self supporting between falsework bents at the time the top slab is placed, provided that the distance between falsework bents does not exceed 4 times the depth of the portion of the girder placed in the preceding concrete placements.

整个上部结构截面除交通障碍，应被视为在一个确定的要求和支持他们的设计应力和挠度除，脚手架时间放在梁的目的如下：对于混凝土箱形梁桥，主梁茎，diaphrams，横梁，和连接底板，如果干墙放置超过5天前向顶板，可能被认为是自我支持之间的脚手架本茨当时顶端板放置，只要脚手架茨之间的距离不超过4倍，在前面的混凝土主梁部分存款放在深度。

The cells in cross-section of leaf and stem become swollen and intercellular space of the ground tissue increass when the expression of UDPGDH gene was inhibited in tobacco. When UDPGDH gene was over expresed, opposite physiological changes were observed. These results further suggested that UDPGDH gene may play an important role in the synthesis of pectin and hemicelluloses in ramie.

初步的组织学分析表明，反义和干扰表达的转基因植株中，茎段与叶横切面细胞结构较为松散，基本组织细胞间隙增大，而在UDPGDH基因过量表达的转基因植株中则观察到相反的现象，进一步证实UDPGDH基因在苎麻半纤维素和果胶合成中所具有的重要作用。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失