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  • 电池组的组织----高级

    Why be organized?

    Why be organized?
    ::为什么组织起来?

    It can be said organization leads to efficiency. And in you, are organized into tissues , which are organized into organs , which are organized into organ systems , which form you. And it can be said that the is a very organized and efficient system.
    ::可以说组织能带来效率。在你身上,组织成组织,组织成器官,组织成器官,组织成器官,组织成器官系统,形成你。可以说,这是一个组织化高效的系统。

    Organization of Cells
    ::单元的组织

    Biological organization exists at all levels in organisms . It can be seen at the smallest level, in the molecules that make up such compounds as and , to the largest level, in an organism such as a blue whale, the largest mammal on Earth. Similarly, single-celled and eukaryotes show order in the way their cells are arranged. Single-celled organisms such as amoeba are free-floating and independent-living. Their single-celled "bodies" are able to carry out all the processes of life such as metabolism and respiration without help from other cells.
    ::生物组织存在于生物的所有层次上,在最小层次上,在构成这种化合物的分子中,以及在最大层次上,在蓝鲸这种地球上最大的哺乳动物等生物体中,可以看到生物组织的存在,同样,单细胞和eukaryotes 显示细胞排列方式的顺序,Amoeba等单细胞生物是自由漂浮和独立生存的,其单细胞“身体”能够在没有其他细胞帮助的情况下进行新陈代谢和呼吸等所有生命过程。

    Some single-celled organisms such as can group together and form a colony. A colony refers to a group of individual organisms of the same that live closely together. This is usually done to benefit the group, such as by providing a stronger defense or the ability to attack bigger prey . A colony can also form from organisms other than bacteria. A bacterial colony often defends from a single organism, producing a colony of genetically identical individuals.
    ::某些单细胞生物,例如可以组合在一起形成一个聚居区。一个聚居区是指一个与同一生物有密切关系的个体生物群体。这通常是为了让该群体受益,例如提供更强大的防御或有能力攻击更大的猎物。一个聚居区也可以由细菌以外的生物组成。一个细菌聚居区常常保护一个单一生物群体,产生一个基因相同的个体聚居区。

    A specific type of colony of microorganisms is a biofilm . A biofilm is a large grouping of many microorganisms that sticks to a surface and makes a protective coating over itself. Biofilms can show similarities to , in the sense that a biofilm will have properties and capabilities greater than the capabilities of the individual organisms.
    ::生物胶卷是一种特定类型的微生物聚居区,生物胶卷是许多微生物组成的大组合,这些微生物粘贴在表面,自我涂层保护。 生物胶卷可以显示与生物胶卷相似之处,即生物胶卷的特性和能力将大于个体生物体的能力。

    Division of labor is the process in which one group of cells does one job (such as making the "glue" that sticks the biofilm to the surface), while another group of cells does another job (such as taking in nutrients). Multicellular organisms carry out their life processes through division of labor and they have specialized cells that have specific functions. However, biofilms are not considered a multicellular organism, but this and other colonial organisms were probably the first step toward the evolution of multicellular organisms.
    ::劳动分工是一组细胞做一项工作的过程(比如将生物胶片粘贴到表面的“胶囊 ” ) , 而另一组细胞做另一项工作(比如养分 ) 。 多细胞生物通过分工进行生命过程,并且有专门的细胞具有特定功能。 然而,生物胶囊不被认为是一种多细胞有机体,但这个和其他殖民生物可能是多细胞有机体进化的第一步。

    Colonial algae of the genus ''Volvox''
    Colonial algae of the genus Volvox.

    Colonial Organisms
    ::殖民生物

    A colony of single-cell organisms is known as colonial organisms . The difference between a multicellular organism and a colonial organism is that the individual organisms that form a colony or biofilm can if separated, survive on their own, while cells from a multicellular organism (e.g., liver cells) cannot.
    ::单细胞生物群落被称为殖民生物,多细胞生物体与殖民生物体之间的区别在于,形成殖民地或生物膜的个体生物体如果分离,可以独立生存,而从多细胞生物体(如肝细胞)中取出的细胞不能独立生存。

    Colonial organisms were probably one of the first evolutionary steps towards multicellular organisms. of the genus Volvox are an example of the bridge between colonial organisms and multicellular organisms. Each Volvox , shown in the Figure  , is a colonial organism. It is made of up to 50,000 photosynthetic algae that are grouped together into a hollow sphere. Volvox live in a variety of freshwater habitats and was first reported by Antonie van Leeuwenhoek in 1700.
    ::殖民地生物可能是朝向多细胞生物迈出的第一个进化步骤之一。 原生伏尔沃克斯是殖民生物与多细胞生物之间桥梁的一个例子。图中显示的每种伏尔沃克斯都是殖民生物,由50 000个光合藻组成,这些藻类被归为空地。伏尔沃克斯生活在各种淡水生境中,1700年由安东尼·范利乌文豪克首次报告。

    The Volvox sphere has a distinct front and back end. The colony of cells can swim in a coordinated fashion. The cells have eyespots, which are more developed in the cells near the front. This enables the colony to swim towards light.
    ::沃尔沃克斯球有不同的前端和后端。 细胞聚居区可以以协调的方式游泳。 细胞有眼盆, 在前面的细胞里比较发达。 这使得聚居区可以游向光线。

    Origin of Multicellularity
    ::多细胞起源

    The oldest known multicellular organism is the red algae Bangiomorpha pubescens , of which were found in 1.2 billion-year-old rock. However, the first organisms were single-celled. How multicellular organisms developed is the subject of much debate.
    ::已知的最古老的多细胞有机体是红藻类Bangioforma阴部动物,其中12亿年之久的岩石中发现了这些生物,然而,第一批生物是单细胞生物,多细胞生物是如何发育的,是引起激烈争论的主题。

    Scientists think that multicellularity arose from cooperation between many organisms of the same species. The Colonial Theory proposes that this cooperation led to the of a multicellular organism. Many examples of cooperation between organisms in nature have been observed. For example, a certain species of amoeba (a single-celled protist) groups together during times of food shortage and forms a colony that moves as one to a new location. Some of these amoebas then become slightly differentiated from each other. Volvox, shown in the Figure  , is another example of a colonial organism. Most scientists accept that the Colonial theory explains how multicellular organisms evolved.
    ::科学家认为,多细胞是由同一物种的许多生物体之间的合作产生的。《殖民理论》建议,这一合作导致多细胞生物体的形成。观察了许多自然生物体之间合作的例子。例如,在食物短缺时,某类阿米亚巴(单细胞原生物体)组群聚集在一起,形成一个聚居区,作为一体迁移到一个新的地点。这些亚米巴斯中有些随后彼此略有不同。图中显示的沃尔沃克斯是殖民生物体的另一个例子。大多数科学家都认为,殖民理论解释了多细胞生物体是如何演变的。

    Multicellular organisms are organisms that are made up of more than one type of cell and have specialized cells that are grouped together to carry out specialized functions. Most life that you can see without a is multicellular. As discussed earlier, the cells of a multicellular organism would not survive as independent cells. The body of a multicellular organism, such as a tree or a cat, exhibits organization at several levels: tissues, organs, and organ systems. Similar cells are grouped into tissues, groups of tissues make up organs, and organs with a similar function are grouped into an organ system.
    ::多细胞有机体是由一种以上种类的细胞组成的有机体,并且有专门细胞,用来执行专门功能。你可以看到的多数生命是多细胞的。如前所述,多细胞有机体的细胞不会作为独立的细胞而生存。多细胞有机体的身体,如树或猫、若干层次的展示组织:组织、器官和器官系统。类似的细胞分为组织、组织组成组织组、器官组和具有类似功能的器官组,而具有类似功能的器官组归一个器官系统。

    Levels of Organization in Multicellular Organisms
    ::多细胞生物组织组织级别

    The simplest living multicellular organisms, , are made of many specialized types of cells that work together for a common goal. Such cell types include digestive cells, tubular pore cells; and epidermal cells. Though the different cell types create a large organized, multicellular structure—the visible sponge—they are not organized into true interconnected tissues. If a sponge is broken up by passing it through a sieve, the sponge will reform on the other side. However, if the sponge’s cells are separated from each other, the individual cell types cannot survive alone. Simpler colonial organisms, such as members of the genus Volvox, as shown in the Figure  , differ in that their individual cells are free-living and can survive on their own if separated from the colony.
    ::最简单的活性多细胞生物是由许多专门类型的细胞组成的,它们为了一个共同的目标而共同工作。这类细胞类型包括消化细胞、管状孔状细胞和上皮细胞。虽然不同的细胞类型创造了一个大型的、有组织的多细胞结构 — — 可见的海绵 — — 它们并没有组织成真正的相互关联的组织。 如果海绵通过一个筛子将海绵分解出来,那么海绵就会在另一侧进行改造。 但是,如果海绵的细胞相互分离,单细胞类型就无法单独生存。 图中显示的较简单的殖民生物,如原生伏伏伏生物,其个体细胞是自由的,如果与聚居区分离,可以独立生存。

    Wild-type ''Caenorhabditis elegans''
    This roundworm, a multicellular organism, was stained to highlight the nuclei of all the cells in its body (red dots).

    A tissue is a group of connected cells that have a similar function within an organism. More complex organisms such as jellyfish, coral, and sea anemones have a tissue level of organization. For example, jellyfish have tissues that have separate protective, digestive, and sensory functions. Though most have many different types of cells, they only have four basic types of tissue: connective, muscle, nervous, and epithelial.
    ::一种组织是由有机体内具有类似功能的连接细胞组成的一组组织。 更复杂的生物,如水母、珊瑚和海葵等,具有组织层次的组织。 比如,水母组织组织具有不同的保护、消化和感官功能。 尽管大多数组织有多种不同的细胞,但它们只有四种基本组织类型:连接、肌肉、神经和上皮细胞。

    Even more complex organisms, such as the roundworm shown in the Figure  , while also having differentiated cells and tissues, have an organ level of development. An organ is a group of tissues that has a specific function or group of functions. Organs can be as primitive as the brain of a (a group of nerve cells), as large as the of a sequoia (up to 90 meters, or 300 feet, in height), or as complex as a human liver.
    ::更复杂的有机体,如图中所示的圆虫,虽然有不同的细胞和组织,但具有器官发育水平,器官是具有特定功能或功能组的一组组织。器官可以像一个(神经细胞组)的大脑一样原始,大如一个sequia(高达90米,或300英尺,身高),或像一个人类肝脏一样复杂。

    The most complex organisms (such as mammals, trees, and flowers) have organ systems. An organ system is a group of organs that act together to carry out complex related functions, with each organ focusing on a part of the task. An example is the human in which the mouth ingests food, the stomach crushes and liquifies it, the pancreas and gall bladder make and release digestive , and the intestines absorb nutrients into the .
    ::最复杂的有机体(如哺乳动物、树木和鲜花)有器官系统。器官系统是一组器官,它们共同发挥作用,履行复杂的相关功能,每个器官都专注于任务的一部分。 一个例子是口部吞食食物、胃部压碎和溶解、胰腺和胆囊制造和释放消化功能以及肠胃吸收营养元素的人类。

    Summary
    ::摘要

    • Single-celled organisms can carry out all the processes of life without help from other cells.
      ::单细胞生物可以在没有其他细胞帮助的情况下进行所有生命过程。
    • Multicellular organisms carry out their life processes through division of labor. They have specialized cells that do specific jobs.
      ::多细胞生物通过分工进行生命过程。它们有专门的细胞,从事特定的工作。
    • The Colonial Theory proposes that cooperation among cells of the same species led to the development of a multicellular organism.
      ::《殖民理论》建议,同一物种细胞之间的合作可导致多细胞有机体的发展。
    • Multicellular organisms, depending on their complexity, may be organized from cells to tissues, organs, and organ systems.
      ::多细胞生物根据其复杂性,可以从细胞组织成组织、器官和器官系统。

    Review
    ::回顾

    1. What is a cell feature that distinguishes a colonial organism from a multicellular organism?
      ::将殖民地生物与多细胞生物区别开来的细胞特征是什么?
    2. What is the difference between a cell and a tissue?
      ::细胞与组织有什么区别?
    3. Describe the levels of organization of an organism.
      ::描述一个生物体的组织水平。