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A Peek Inside the Cell
::囚室里一个屁屁This may look like a colorful work of abstract art or maybe an ultra-modern carpet design, but it's neither. It is actually a model of the interior of a . It's an artist's representation of what you might see if you could take a peek inside one of these basic building blocks of living things. A cell's interior is obviously a crowded and busy space. It contains cytoplasm , dissolved substances, and many structures. It's a hive of countless biochemical activities all going on at once.
::这也许看起来像一个多彩的抽象艺术作品, 或者可能是超现代地毯设计, 但两者都不是。 它实际上是一个内部的模型。 它是一个艺术家的表象, 说明你可以看到的事物, 如果你可以看一眼这些基本的基本建筑。 细胞的内部显然是一个拥挤和繁忙的空间。 它包含细胞图象, 溶解物质, 以及许多结构。 它是一个无数生物化学活动的蜂窝, 它们同时进行着。Cytoplasm
::结晶Cytoplasm is a thick, usually colorless solution that fills each cell and is enclosed by the . Cytoplasm presses against the cell membrane, filling out the cell and giving it its shape. Sometimes, cytoplasm acts like a watery solution, and sometimes, it takes on a more gel-like consistency. In eukaryotic cells , the cytoplasm includes all of the material inside the cell but outside of the , which contains its own watery substance called the nucleoplasm. All of the in eukaryotic cells (such as the and mitochondria) are located in the cytoplasm. The cytoplasm helps to keep them in place. It is also the site of most metabolic activities in the cell, and it allows materials to pass easily throughout the cell.
::圆顶晶体是一种厚厚的、通常是无色的溶液,填充每个单元格,并被封闭在封闭室内。 圆顶晶体压压住细胞膜,填充细胞并给其形状。 有时, 圆顶晶体像水溶液一样, 有时, 它具有更凝胶一样的一致性。 在电子细胞中, 圆顶晶体包括细胞内的所有材料, 但是在细胞外, 它含有它自己的水物质, 叫做核核核糖核。 所有在单体内的细胞( 如核糖核酸和核糖核酸)都位于细胞膜内。 圆顶晶体细胞有助于将它们固定在原地上。 它也是细胞中大多数代谢活动的地点, 它使材料很容易通过整个细胞。The portion of the cytoplasm surrounding organelles is called cytosol . Cytosol is the liquid part of cytoplasm. It is composed of about 80 percent , and it contains dissolved salts, fatty acids , sugars, amino acids , and (such as enzymes). These dissolved substances are needed to keep the cell alive and carry out metabolic processes. dissolved in cytosol, for example, break down larger molecules into smaller products that can then be used by organelles of the cell. Waste products are also dissolved in the cytosol before they are taken in by vacuoles or expelled from the cell.
::环绕有机体的细胞板块部分称为细胞索。 细胞索是细胞托拉斯的液体部分。 它由大约80%的溶解盐、脂肪酸、糖、氨基酸和(如酶)组成。 这些溶解物质是保持细胞活性并进行代谢过程所必需的。 例如, 溶解在细胞索中, 将较大的分子分解成较小的产品, 然后由细胞的器官使用。 废品在被蒸气吸进细胞或从细胞中分离出来之前, 也会在细胞索中溶解。Cytoskeleton
::Cytoskeleton( 中位元)Al though cytoplasm may appear to have no form or structure, it is actually highly organized. A framework of protein scaffolds called the cytoskeleton provides the cytoplasm and the cell with structure. The cytoskeleton consists of thread-like filaments and tubules that criss-cross the cytoplasm. You can see these filaments and tubules in the cells in the figure . As its name suggests, the cytoskeleton is like a cellular “skeleton.” It helps the cell maintain its shape and also helps to hold cell structures (like organelles) in place within the cytoplasm.
::虽然细胞图层似乎没有形态或结构,但它实际上组织严密。一个叫做细胞骨质板的蛋白脚架框架提供了细胞图层和细胞结构。细胞图层由线状丝和管状组成,穿过细胞图层。你可以看到图中细胞中的这些丝状和管状。如其名称所示,细胞板骨质板像一个细胞“细胞 ” 。它帮助细胞保持其形状,并帮助将细胞结构(如有机物)放在细胞图中。Cytoskeleton. The cytoskeleton gives the cell an internal structure, like the frame of a house. In this photograph, filaments and tubules of the cytoskeleton have been stained green and red, respectively, so that they can be seen clearly. The blue dots are cell nuclei.
::Cytoskeleton 。 cytoskeleton 给细胞一个内部结构, 像房子的架子。 在这张照片中, 细胞stoskeleton 的丝质和管子分别染上绿色和红色, 以便清晰可见 。 蓝色点是细胞核 。Feature: Human Biology in the News
::特著:《新闻》中的人类生物学News about an important study of the cytoplasm of eukaryotic cells came out in early 2016. Researchers in Dresden, Germany discovered that when cells are deprived of adequate nutrients , they may essentially shut down and become dormant. Specifically, when cells do not get enough nutrients, they shut down their metabolism , their energy level drops, and the pH of their cytoplasm decreases. Their normally liquid cytoplasm also assumes a solid state. The cells appear dead, as though a kind of rigor mortis has set in. The researchers think that these changes protect the sensitive structures inside the cells and allow the cells to survive difficult conditions. If nutrients are returned to the cells, they can emerge from their dormant state unharmed. They will continue to grow and multiply when conditions improve.
::2016年初,德国德累斯顿的研究人员发现,当细胞缺乏足够的营养物质时,他们可能基本上关闭并休眠。 具体地说,当细胞得不到足够的营养物质时,他们就关闭了新陈代谢、能量水平下降和细胞温度下降的pH值。它们通常的液态囊肿也呈现一种坚固的状态。细胞似乎已经死亡了,就像一种硬质的死尸。研究人员认为这些变化可以保护细胞内部的敏感结构,并允许细胞在困难的条件下生存。如果将营养物质送回细胞,它们就能从休眠状态中不受伤害地出现。当条件改善时,它们会继续成长和增加。This important basic science research was executed on a nonhuman organism : one-celled called yeasts. Nonetheless, it may have important implications for humans, because yeasts have eukaryotic cells with many of the same structures as human cells. Yeast cells appear to be able to "trick" death by shutting down all life processes in a controlled way. Through continued study, researchers hope to learn whether human cells can be taught this "trick" as well.
::这项重要的基础科学研究是在非人类生物身上进行的:一个叫酵母的细胞。尽管如此,它对人类可能具有重要的影响,因为酵母的细胞与人类细胞有许多相同的结构。 酵母的细胞似乎能够通过以控制的方式关闭所有生命过程而“触发”死亡。 通过持续的研究,研究人员希望了解人类细胞是否可以被教授这个“trick” 。Summary
::摘要-
Cytoplasm is a thick solution that fills a cell and is enclosed by the cell membrane. It has many functions. It helps give the cell shape, holds organelles, and provides a site for many of the biochemical reactions inside the cell.
::Cytoplasm 是一个填充细胞的厚溶液, 并被细胞膜封闭。 它有许多功能。 它有助于给细胞形状、 握住风琴, 并为细胞内的许多生化反应提供一个场地 。 -
The liquid part of the cytoplasm is called cytosol. It is mainly water, and it contains many dissolved substances. The cytoplasm of a eukaryotic cell also contains a membrane-enclosed nucleus and other organelles.
::细胞顶板的液体部分称为细胞溶液,主要是水,含有许多溶解物质。单体细胞的细胞顶板也含有膜内核和其他有机物。 -
The cytoskeleton is a highly organized framework of protein filaments and tubules that criss-cross the cytoplasm of a cell. It gives the cell structure and helps hold cell structures (such as organelles) in place within the cytoplasm.
::Citoskeleton是一个由蛋白丝和管状体组成的高度有组织的框架,它穿过细胞的细胞的细胞图层,提供细胞结构并帮助将细胞结构(如有机物)固定在细胞图层内。
Review
::回顾1. Describe the composition of cytoplasm.
::1. 描述囊虫的构成。2. What are some of the functions of cytoplasm?
::2. 细胞顶板的功能是什么?3. Outline the structure and functions of the cytoskeleton.
::3. 概述cytoskeleton的结构和功能。4. Is the cytoplasm made of cells? Why or why not?
::4. 细胞板是由细胞制成的,为什么或为什么不是?5. Name two types of cytoskeletal structures.
::5. 列出两种细胞骨骼结构。6. True or False: The cytoplasm is usually green.
::6. 真实或假:圆顶虫通常是绿色的。7. True or False: The nucleus of a cell is filled with cytoplasm.
::7. 真实或假:单元格核心装有细胞托盘。8. In the picture of the different cytoskeletal structures above (shown in red and green), what do you notice about these different structures?
::8. 在以上(红色和绿色)不同细胞骨骼结构图中,你对这些不同结构有何看法?9. Describe one example of a metabolic process that happens in the cytosol.
::9. 描述在细胞索中发生代谢过程的一个例子。10. In eukaryotic cells, all of the material inside of the cell, but outside of the nucleus is called the ___________ .
::10. 在尿道细胞中,细胞内的所有材料,但核外的材料都称为。11. What is the liquid part of cytoplasm called?
::11. 细胞顶板的液体部分叫什么?12. What chemical substance composes most of the cytosol?
::12. 什么化学物质构成大部分细胞索?13. When yeast cells deprived of nutrients go dormant, their cytoplasm assumes a solid state. What effect do you think a solid cytoplasm would have on normal cellular processes? Explain your answer.
::13. 当缺乏营养的酵母细胞休眠时,它们的细胞顶片假定为固态,认为固态的细胞顶片会对正常细胞过程产生什么影响?解释一下答案。Explore More
::探索更多Watch the video below to learn about motor proteins, which transport cellular material by the cytoskeleton.
::观看下面的视频, 了解运动蛋白质, 由细胞素传递细胞素。The video below describes the cell's cytoplasm.
::下面的视频描述了细胞的细胞图层。 -
Cytoplasm is a thick solution that fills a cell and is enclosed by the cell membrane. It has many functions. It helps give the cell shape, holds organelles, and provides a site for many of the biochemical reactions inside the cell.
