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  • 生物学基本原则

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    Why Are Humans Such Sweaty Animals?
    ::为什么人类是这种有汗味的动物?

    Combine and a hot day, and you get sweat — and lots of it. Sweating is one of the adaptations humans have evolved to maintain , or a constant internal environment. When sweat evaporates from the skin, it uses up some of the excess heat energy on the skin, thus helping to reduce the body's temperature. Humans are among the sweatiest of all , with a fine-tuned ability to maintain a steady internal temperature, even at very high outside temperatures.
    ::混合和炎热的一天,你会出汗 — — 以及大量汗水。湿润是人类为了维持或维持一个稳定的内部环境而进化的适应性变化之一。当汗水从皮肤中蒸发时,它会利用皮肤上的一些超热能,从而帮助降低身体的温度。人类是最出血最深的人群之一,拥有保持稳定的内部温度的精细调整能力,即使是在非常高的温度之外。

    Unifying Principles of Biology
    ::统一生物学原则

    All living things have mechanisms for homeostasis. Homeostasis is one of four basic principles or theories that explain the structure and function of all species (including our own) .  W hether biologists are interested in ancient life, the life of , or how humans could live on Mars, they base their understanding of biology on these unifying principles:
    ::所有生物都有自成一体的机制。 自成一体是解释所有物种(包括我们自身)结构和功能的四项基本原则或理论之一。 无论生物学家对古代生命、生命或人类如何在火星上生活感兴趣,他们对生物学的理解都基于这些统一的原则:

    • gene theory
      ::基因理论
    • homeostasis
      ::常久久久久久久久
    • evolutionary theory
      ::进进理论

    Cell Theory
    ::细胞理论

    According to cell theory , all living things are made of , and living cells come only from other living cells. Each living thing begins life as a single cell. Some living things, including bacteria, remain single-celled. Other living things, including plants and , grow and develop into many cells. Your own body is made up of an amazing 100 trillion cells. But even you — like all other living things — began life as a single cell.
    ::根据细胞理论,所有生物都是由......组成的,活细胞只来自其他生物细胞。每个生物细胞都以单一细胞开始生命。有些生物,包括细菌,仍然是单一细胞。其他生物,包括植物和植物,生长和成长成许多细胞。你的身体是由惊人的100万亿细胞组成的。但即使你——和其他所有生物细胞一样——也以单一细胞开始生命。

    Gene Theory
    ::产生理论

    Gene theory is the idea that the characteristics of living things are controlled by genes , which are passed from parents to their offspring. Genes are located on larger structures called . Chromosomes are found inside every cell, and they consist of molecules of (deoxyribonucleic acid). Those molecules of DNA are encoded with instructions that "tell" cells how to behave .
    ::Gene理论认为,生物的特性是由基因控制的,基因从父母传给后代。基因位于更大的结构上,称为“染色体 ” 。每个细胞中都发现染色体,它们由(脱氧核糖核糖核酸)分子组成。这些DNA分子被编码成“告诉”细胞如何行为的指令。

    Homeostasis
    ::常态

    Homeostasis , or the condition in which a system is maintained in a more-or-less steady state, is a characteristic of individual living things, like the human ability to sweat. Homeostasis also applies to the entire , wherever life is found on Earth. Consider the concentration of oxygen in Earth's atmosphere . Oxygen makes up 21 percent of the atmosphere, and this concentration is fairly constant. What maintains this homeostasis in the atmosphere? The answer is living things .
    ::保持恒定状态, 也就是一个系统维持在更或更稳定状态中的状况, 是个体生活事物的特征, 就像人类出汗的能力。 保持恒定状态也适用于整个地球, 不论地球上发现的生命在哪里。 考虑一下地球大气中氧的浓度。 氧占大气的21%, 而这种浓度相当稳定。 在大气中保持这种恒定状态的原因是什么? 答案是活的东西 。

    Most living things need oxygen to survive, so they remove oxygen from the air. On the other hand, many living things, including plants, give off oxygen when they convert carbon dioxide and to food in the process of .  These two processes balance out so the air maintains a constant level of oxygen. 
    ::大部分生物都需要氧气才能生存,所以它们从空气中去除氧气。另一方面,许多生物,包括植物,在将二氧化碳和食物转换成二氧化碳的过程中,会释放氧气。这两个过程平衡,空气保持恒定的氧气水平。

    Evolution
    ::演变演变进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进进

    Evolution is a change in the characteristics of of living things over time. Evolution can occur by a process called , which   results from random genetic in a population. If these mutations lead to changes that allow th e living things  to better survive, then their chances of surviving and reproducing in a given environment increase. They will then  pass more genes to the next generation. Over many generations, this can lead to major changes in the characteristics of those living things. Evolution explains how living things are changing today, as well as how modern living things descended from ancient life forms that no longer exist on Earth.
    ::进化是生命特性随时间变化的进化。进化可以由被称为由人口随机遗传产生的过程发生。如果这些突变导致改变,使生命更好地生存下去,那么在特定环境中生存和再生的机会就会增加。然后,它们会把更多的基因传给下一代。在许多代人中,这可以导致这些生物特性的重大变化。进化解释了生命事物今天是如何变化的,以及现代生物是如何从地球上不再存在的古代生命形式中诞生的。

    Traits that help living things survive and reproduce in a given environment are called adaptations . You can see an obvious adaptation in the image . The chameleon is famous for its ability to change its color to match its background as camouflage. Using camouflage, the chameleon can hide in plain sight .
    ::有助于生活事物在特定环境中生存和繁殖的轨迹被称为适应。您可以看到图像中的明显适应。变色龙因其能够改变颜色以与背景相匹配而成为伪装而出名。利用伪装,变色龙可以隐藏在普通的视野中。

    A chameleon exhibits its color changing adaptation to match its background.
    ::变色龙展示了颜色变化的适应性 以适应其背景

    Feature: Myth vs. Reality
    ::特征:神话对现实

    Misconceptions about evolution are common. They include the following myths:
    ::对进化的误解是常见的。 其中包括以下神话:

    Myth: Evolution is "just" a theory or educated guess. 
    ::传说:进化只是一种理论或教育性的猜测。

    Reality:  Scientists accept evolutionary theory as the best explanation for the diversity of life on Earth because of the large body of scientific evidence supporting it. Like any , evolution is a broad, evidence-supported explanation for multiple phenomena.
    ::现实:科学家接受进化理论作为地球上生命多样性的最佳解释,因为有大量科学证据支持它。 与任何科学证据一样,进化是对多种现象的广泛、有证据支持的解释。

    Myth: The explains how life on Earth began.
    ::神话:它解释了地球上的生命是如何开始的。

    Reality: The theory of evolution explains how life changed on Earth after it began.
    ::现实:进化理论解释生命在地球开始后是如何变化的。

    Myth: The theory of evolution means that humans evolved from apes like those in zoos.
    ::传说:进化理论意味着 人类从动物园中的猿类进化而来。

    Reality: Humans and modern apes both evolved from a common ape-like ancestor millions of years ago.
    ::现实:人类和现代猿类 都从数以百万计的 类人猿祖先演变而来。

    Summary
    ::摘要

    • Four basic principles or theories unify all fields of biology. Those principles are cell theory, gene theory, homeostasis, and evolutionary theory.
      ::四个基本原则或理论统一了生物学的所有领域。 这些原则是细胞理论、基因理论、自闭症和进化理论。
    • According to cell theory, all living things are made of cells and come from other living cells.
      ::根据细胞理论 所有生物都是由细胞组成的 并且来自其他生物细胞
    • Gene theory states that the characteristics of living things are controlled by genes that pass from parents to offspring.
      ::Gene理论指出,生物的特性受从父母传给后代的基因控制。
    • All living things — and even the entire biosphere as a whole — strive to maintain internal balance, or homeostasis.
      ::所有生物——甚至整个生物圈——都努力保持内部平衡,或保持原状。
    • The characteristics of populations of living things change over time through the process of evolution as organisms acquire adaptations, or traits that better suit them to a given environment.
      ::随着进化过程,生物体的特征随着时间的变化而变化,生物体获得适应性,或更适合特定环境的特性。

    Review
    ::回顾

    1. How does sweating help the human body maintain homeostasis?
    ::1. 出汗如何帮助人体保持自足?

    2. Explain  cell theory and gene theory.
    ::2. 解释细胞理论和基因理论。

    3. Describe an example of homeostasis in the atmosphere.
    ::3. 描述大气层中自闭症的一个例子。

    4. Describe how you can apply the concepts of evolution, natural selection, adaptation, and homeostasis to the human ability to sweat.
    ::4. 描述如何将进化、自然选择、适应和顺从等概念应用于人类出汗能力。

    5. Which of the four unifying principles of biology is primarily concerned with:
    ::5. 生物学的四项统一原则中,其中哪一项主要涉及:

    a. how DNA is passed down to offspring?
    ::a. DNA是如何传给后代的?

    b. how internal balance is maintained?
    ::b. 如何维持内部平衡?

     

     6. _____________ are located on ______________.
    ::6. 位于___________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

    a. chromosomes; genes
    ::a. 染色体;基因

    b. genes; chromosomes
    ::b. 基因;染色体

    c. genes; traits
    ::c. 基因;特性

    d. none of the above
    ::d. 以上无任何内容

     

    7. Define an adaptation and give one example.
    ::7. 界定适应,举一个例子。

     

    8. True or False:  The theory of evolution  addresses how life began, not how it has changed since  it began.
    ::8. 真理或假:进化理论涉及的是生命的起源,而不是生命自开始以来的变化。

     

    9.  True or False:  Modern apes were  our direct ancestors.
    ::9. 真理或假:现代猿是我们的直接祖先。

     

    10. Explain what the reading means when it says “you began life as a single cell.”
    ::10. 解释读物中写着 " 你作为一个单细胞开始生活 " 是什么意思。

     

    11. Explain how gene theory and evolutionary theory relate to each other.
    ::11. 解释基因理论和进化理论如何相互联系。

     

    12. Does evolution by natural selection occur within one generation? Why or why not?
    ::12. 自然选择的演变是否发生在一代人之内?为什么或为什么不是?

     

    13. Explain why you think chameleons evolved the ability to change their color to match their background, as well as  how natural selection may have acted on the ancestors of chameleons to produce this adaptation.
    ::13. 解释一下为什么你认为变色龙进化了改变颜色以符合其背景的能力,以及自然选择如何影响变色龙的祖先来产生这种适应性。

    Explore More
    ::探索更多

    Learn more about  the  common misconceptions surrounding  evolution.
    ::更多了解关于演变的常见误解。

     Learn more about how the human body regulates its temperature through sweating.
    ::更多了解人体如何通过出汗调节温度。