1.10域
Section outline
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What do you have in common with pond scum?
::你跟池塘人渣有什么共同点?Humans are in the same domain as trees and , which makes up the "pond scum" you see here. What could they possibly have in common? It is the location of their inside their cells . Their cells all have a that is home to their genetic material .
::人类与树木和树木一样, 它们组成了这里看到的“人渣 ” ( pond scum) 。 他们有什么共同之处? 这是他们细胞内部的位置。 他们的细胞都有一个基因材料的家。The Domains of Life
::生命领域Let’s explore the domain , the least specific category of .
::让我们探索这个领域,All of life can be divided into three domains, based on the type of cell of the organism :
::根据生物细胞的类型,所有生命可以分为三个领域:- Bacteria : cells do not contain a nucleus.
::细菌:单元格不包含核。
- : cells do not contain a nucleus; they have a different cell wall from bacteria.
:::细胞不包含核;细胞与细菌的细胞壁不同。
- Eukarya : cells do contain a nucleus.
::Eukarya: 单元格确实包含一个核 。
Archaea and Bacteria
::阿尔恰亚和细菌The Archaea and Bacteria domains ( Figure ) are both entirely composed of small, single-celled organisms and seem very similar, but they also have significant differences. Both are composed of prokaryotic cells , which are cells without a nucleus. In addition, both domains are composed of species that reproduce asexually ( asexual reproduction ) by dividing in two. Both domains also have species with cells surrounded by a cell wall , however, the cell walls are made of different materials. Bacterial cell walls contain the polysaccharide peptidoglycan . Lastly, Archaea often live in extreme environments including hot springs, geysers, and salt flats. Bacteria do not live in these environments.
::考古和细菌区域(图)完全由小的单细胞生物组成,看起来非常相似,但也有显著的差别,两者由没有核细胞的人工细胞组成;此外,这两个区域由通过分裂产生性生殖(性生殖)的物种组成;这两个区域也由细胞墙包围的细胞物种组成,但细胞墙是由不同材料组成的。细菌细胞墙含有多细胞细胞细胞。最后,Archaea经常生活在极端环境中,包括温泉、玻璃和盐滩。细菌并不生活在这些环境中。The Group A Streptococcus organism ( left ) is in the domain Bacteria, one of the three domains of life. The Halobacterium ( right ) is in the domain Archaea, another one of the three domains.
::A Sreptococccus 组有机体( 左) 属于细菌, 属于生命的三个领域之一。 Halobactirium (右) 属于 Archaea 类, 属于另外三个领域之一 。Eukarya
::欧库亚亚All of the cells in the domain Eukarya keep their genetic material, or DNA , inside the nucleus . The domain Eukarya is made up of four kingdoms:
::Eukarya域内的所有细胞都保留着基因材料或DNA在核中。Eukarya域由四个王国组成:- Plantae: Plants, such as trees and grasses, survive by capturing energy from the sun, a process called .
::植物,如树木和草,通过从太阳中捕捉能量而存活下来。
- : Fungi, such as mushrooms and , survive by "eating" other organisms or the remains of other organisms. These organisms absorb their nutrients from other organisms.
::菌类,如蘑菇,通过“食用”其他生物体或其它生物体的残骸存活下来,这些生物体吸收其他生物体的养分。
- Animalia: Animals also survive by eating other organisms or the remains of other organisms. Animals range from tiny ants to the largest whales, and include , , , , and mammals ( Figure ).
::动物:动物也通过食用其他生物或其它生物的残骸生存下来,动物从小蚂蚁到最大的鲸鱼不等,包括...、...、...和哺乳动物(图)。
- Protista : Protists are not all descended from a single common ancestor in the way that plants, animals, and fungi are. Protists are all the eukaryotic organisms that do not fit into one of the other three kingdoms. They include many kinds of microscopic one-celled (unicellular) organisms, such as algae and plankton, but also giant seaweeds that can grow to be 200 feet long.
::Protista : Protista: Protista : 植物、动物和真菌并非都是从同一个共同祖先中降生的。 Protista : Protista : Protista : Protister 并非都是植物、动物和真菌。 Protista : Protista : Protister 并非都是来自植物、动物和真菌那样的单一祖先。 Protista : Protister 并不是所有与其它三个王国中任何一个王国不相容的蛋白质生物。 它们包括多种微型单细胞(单细胞)生物, 如藻类和浮游生物, 但也包括可以长200英尺长的巨型海藻。
Diversity of Animals. These photos give just an inkling of the diversity of organisms that belong to the animal kingdom. (A) Sponge, (B) Flatworm, (C) Flying Insect, (D) Frog, (E) Tiger, (F) Gorilla.
::动物的多样性。这些照片只是说明动物王国生物的多样性。 (A) 海绵,(B) 扁虫,(C) 飞虫,(D) 青蛙,(E) 老虎,(F) 大猩猩。Plants, animals, fungi, and protists might seem very different, but remember that if you look through a , you will find similar cells with a membrane-bound nucleus in all of them. These are eukaryotic cells . These cells also have membrane-bound , which prokaryotic cells lack. The main characteristics of the three domains of life are summarized in Table .
::植物、动物、真菌和蛋白质细胞可能看起来非常不同, 但记住, 如果你通过一个, 你会发现类似的细胞, 在所有细胞中都有一个膜状核。 这些细胞都是阴性细胞。 这些细胞也有膜状细胞, 而蛋白质细胞却缺乏。 表格中总结了三个生命领域的主要特征 。Archaea Bacteria Eukarya Multicelluar No No Yes Cell wall Yes, without peptidoglycan Yes, with peptidoglycan Varies. Plants and fungi have a cell wall; animals do not. Nucleus (Membrane-Enclosed DNA) No No Yes Membrane-Bound Organelles No No Yes Summary
::摘要- All life can be classified into three domains: Bacteria, Archaea, and Eukarya.
::所有生命可分为三个领域:细菌、Archaea和Eukarya。
- Organisms in the domain Eukarya keep their genetic material in a nucleus and include the plants, animals, fungi, and protists.
::Eukarya领域的生物体将基因材料保留在核中,包括植物、动物、真菌和原生生物。
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。- Exploring Deep-Subsurface: Life Domains at (8:02)
::探索地下深层:生命领域(8:02)
- What are the three domains of life?
::生活的三个领域是什么?
- What category do the individual organisms that we can see with our naked eye fall into?
::我们用肉眼可以看到的个体生物 属于哪一类?
- What is an extremophile? What domain is known for these organisms? (Note: recent work has shown that extremophiles are not the only members of this domain.)
::极端恋童癖是什么?这些生物的已知领域是什么? (注:最近的工作表明,极端恋童癖不是这个领域的唯一成员。 )
- How do Archaea and Bacteria differ? How are they the same?
::Archaea和Blassia有什么不同?它们如何相同?
- Which domain of life seems to be absent for deep-subsurface communities?
::深层地下社区似乎缺少哪个生活领域?
Review
::回顾- Compare and contrast the domains Archaea and Bacteria.
::比较和对比 Archaea 和 Blassiana 的域 。
- What are the four kingdoms that make up the domain Eukarya?
::构成欧卡里亚领地的四个王国是什么?
- Name three different examples of organisms in the domain Eukarya.
::举三个不同例子来说明Eukarya域的生物体。
- Bacteria : cells do not contain a nucleus.
