地球生命的起源-英文版(origin of life on earth)
地球的起源简述英语作文
地球的起源简述英语作文The origin of Earth is a fascinating subject that has captivated scientists and thinkers for centuries. While there are various theories and hypotheses, the prevailing scientific understanding is rooted in the formation of the solar system about 4.6 billion years ago. Here's a brief overview of Earth's origin:Formation of the Solar System:The solar system formed from a giant molecular cloud composed mostly of hydrogen and helium, along with traces of other elements. Around 4.6 billion years ago, a nearby supernova explosion or a passing star's gravitational disturbance triggered the collapse of part of this cloud. As the cloud collapsed, it began to rotate and flatten into a spinning disk, with the densest material accumulating at the center.Formation of the Protosun and Protoplanetary Disk:At the center of this spinning disk, the densest region eventually formed the protosun, while the surrounding material coalesced into a swirling disk called the protoplanetary disk. Within this disk, smaller clumps of matter called planetesimals began to form throughcollisions and gravitational attraction.Accretion and Differentiation:Over millions of years, these planetesimals collided and merged, forming larger bodies known as protoplanets. The intense heat generated by these collisions, as well as the decay of radioactive elements, led to the melting and differentiation of these protoplanets. Heavier elements sank towards the center, forming Earth's core, whilelighter materials rose to the surface, forming the mantle and crust.Formation of Earth:Earth, like other terrestrial planets, gradually tookshape through the process of accretion and differentiation. It is believed that Earth's core formed within the first10-20 million years of the solar system's formation. The core continued to grow as it attracted more material, while the mantle and crust formed from the cooling and solidification of molten rock.Early Earth and the Origin of Life:During its early history, Earth was bombarded by asteroids and comets, a period known as the Late Heavy Bombardment. Despite this tumultuous environment, conditions on Earth gradually became more hospitable for life. The exact origin of life on Earth remains a topic of scientific investigation, but it is believed to have arisen from simple organic molecules in the primordial soup of Earth's oceans, possibly catalyzed by volcanic activity or chemical reactions at hydrothermal vents.In summary, Earth's origin is intimately linked to the formation of the solar system, which began with the collapse of a giant molecular cloud and culminated in theaccretion and differentiation of planetesimals to form our planet. The story of Earth's origin is a testament to the intricate processes of cosmic evolution that have shaped our world over billions of years.。
生物专业英语第六章生命的起源
18. ozone layer n. 臭氧层
[ 'əuzəune atmosphere, about 20 to 50 km above the surface, which contains ozone produced by ultraviolet radiation.
起源的时间
科学回答生命起源的时间--- 化石 迄今为止，我们发现了最古老的生物化石是来自 澳大利亚西部，距今约三十五亿年前的岩石，这 些化石类似于现在的蓝藻，它们是一些原始的生 命，是肉眼看不见的。它的大小只有几个微米， 到几十个微米。 同时我们知道地球的形成年龄大约在46亿年前， 这两个数据我们就可以看到生命起源的年龄，大 致可以界定在46亿年到35亿年之间。
Words and phrases
1.Big Bang
n. 大爆炸
宇宙大爆炸(Big Bang)
大约在150亿年前，宇宙所有的物质都高度密集在一 点，有着极高的温度，因而发生了巨大的爆炸。大 爆炸以后，物质开始向外大膨胀，就形成了今天我 们看到的宇宙。在这150亿年中先后诞生了星系团、 星系、我们的银河系、恒星、太阳系、行星、卫星 等。人类就是在这一宇宙演变中诞生的。
生命起源的几种假说
创世说--《圣经》上说，"起初，神创造天地"。 自生论--生命是从无生命物质自然发生的。如希 腊人认为，昆虫生于土壤，春天万象更新，种子 从泥土里萌发，昆虫从去年留下的卵壳中破壳而 出。还有比如说埃及人认为生命来自于尼罗河， 在中国古代也有腐草生萤之说。 宇宙生命论--提倡“一切生命来自宇宙”观点， 认为地球上最初的生命来自宇宙间的其他星球， 即“地上生命，天外飞来”。这一假说认为，宇 宙太空中的“生命胚种”可以随着陨石或其他途 径跌落在地球表面，即成为最初的生命起点。
地球起源介绍英文作文
地球起源介绍英文作文英文：The origin of the Earth is a fascinating topic that has been studied by scientists for many years. There are several theories about how our planet came to be, but the most widely accepted one is the Nebula theory.According to this theory, the Earth was formed about 4.5 billion years ago from a cloud of gas and dust called a nebula. The nebula was made up of mostly hydrogen and helium, with small amounts of other elements like carbon, nitrogen, and oxygen.Over time, gravity caused the gas and dust in the nebula to come together and form clumps. These clumps eventually became large enough to form planets, including the Earth.As the Earth formed, it became very hot and molten. Theheat was generated by the collisions of the particles that made up the planet. As the Earth cooled, the heavier elements sank to the center and the lighter elements roseto the surface. This process is called differentiation.中文：地球的起源是一个令人着迷的话题，科学家们已经研究了许多年。
origin由来例句
origin由来例句
以下是一些关于“origin”的例句：
1. The genesis of quantum mechanics is a fascinating story of human ingenuity and perseverance. （量子力学的起源是人类智慧和毅力的迷人
故事。
）
2. The meteorite hypothesis for the origin of life on Earth posits that life began on the planet as a result of chemical reactions in space rocks. （地球上生命的起源的陨星假说认为，生命是由于太空岩石中的化学反应而出现在这个星球上的。
）
3. He presented a new concept of the beginning of the universe, positing that it emerged from a singularity of infinite density and spacetime curvature. （他提出了宇宙起源的新概念，认为宇宙是从一个密度无限大、时空曲率无限的奇点中产生的。
）
4. It has been difficult to ascertain the correct source of origin for this scientific theory. （确定这一科学理论的正确起源一直很困难。
）
以上例句仅供参考，可以查阅英汉词典或英文文献，获取更多关于“origin”的例句。
地球的起源简述英语作文
地球的起源简述英语作文下载温馨提示:该文档是我店铺精心编制而成，希望大家下载以后，能够帮助大家解决实际的问题。
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The origin of Earth is a fascinating topic that has intrigued scientists for centuries. There are several theories about how our planet came into existence, and each one has its own unique perspective.One of the most popular theories is the Big Bang theory. According to this theory, the universe began as a singularity, a tiny point of infinite density and temperature. This singularity then exploded, creating the universe as we know it today. Over time, stars and planets formed from the debris of the explosion, including Earth.Another theory is the Nebula Hypothesis. This theory suggests that our solar system formed from a cloud of gas and dust known as a nebula. As the nebula collapsed underits own gravity, it began to spin, forming a disk shape. Eventually, the material in the disk began to clumptogether, forming planets like Earth.A third theory is the Capture Theory. This theory suggests that Earth was originally a rogue planet that was wandering through space. As it passed by the Sun, the Sun's gravity captured it, pulling it into orbit around the star. Over time, the planet cooled and formed the familiar features we see today.Regardless of which theory is correct, one thing is clear: Earth is a unique and remarkable planet. From its diverse ecosystems to its complex geology, our planet continues to fascinate and inspire us. As we continue to explore and learn more about Earth's origins, we gain a deeper understanding of our place in the universe.。
地球起源介绍英文作文
地球起源介绍英文作文The origin of the Earth can be traced back to about 4.6 billion years ago, when it was formed from the dust and gas in the early solar system. It was a chaotic time of collisions and mergers, as the Earth slowly took shape.Fast forward to about 4 billion years ago, and the Earth was a hot and violent place, with constant volcanic activity and frequent asteroid impacts. It was during this time that the first oceans and atmosphere began to form.As the Earth continued to cool, life began to emerge. The earliest forms of life were simple, single-celled organisms that thrived in the harsh conditions of the early Earth.Over millions of years, these simple organisms evolved into more complex life forms, eventually leading to the diverse array of plants, animals, and microorganisms that we see today.Throughout its history, the Earth has experienced numerous mass extinctions, where a large percentage of species were wiped out. These events have shaped the course of evolution and have played a major role in determining which species would come to dominate the planet.Today, the Earth is a dynamic and ever-changing planet, with its own unique mix of geology, climate, and life. Itis a testament to the incredible journey that our planet has taken to reach its current state.。
The origin of life on Earth
The origin of life on Earth 地球上生命的起源地球上的生命是一个神秘而又惊人的话题。
尽管我们已经研究了几百年，但我们还是无法确定生命是从哪里来的，或者说是如何在地球上生成的。
然而，许多科学家仍然在努力寻找关于生命起源的答案。
然而，我们已经知道了一些关于生命起源的基本事实。
生命的基础生命的基础是由分子和化学反应组成的。
然而，在现代有机分子生物学中，人们已经发现了一些最早的生命形式可能是以RNA为基础的。
RNA是一个类似于DNA的分子，它可以自我复制和发挥关键的催化作用。
此外，许多对RNA的研究表明，一些RNA可以自动组装形成更大的复合物，还能基于一组配对规则来自拼装模块。
这些性质为构建RNA生命的可能性提供了基础。
然而，RNA不能解释生命的所有特征，例如膜、代谢和能量转换。
因此，许多科学家认为，RNA可能只是生命起源的一部分。
化学反应与生命起源生命的起源与地球早期的化学反应有关。
在这个初始的环境中，地球表面由各种不同的化学物质组成，因此有机分子（如氨基酸、碳水化合物、核酸和脂质）可能已经在地球表面及其周围形成。
在早期的环境中，许多化学过程都具有催化剂。
例如，来自热水喷泉的矿物质可能会催化含氮基团的分子的反应。
此外，紫外线会引起分子解离和生成自由基的过程，这也有利于生命分子的合成。
生命的起源模型许多关于生命起源的模型都需要考虑生命起源的基本特征。
例如，生命必须能够自我复制、转运和进行代谢反应。
另外，一个完整的模型必须可以解释形成有机分子的化学反应、表面催化剂，以及其他有利于有机分子逐渐从简单到复杂的分子演化过程。
生命起源的大致模型包括：①混沌模型：该模型主要是基于早期地球的化学环境，在此环境中，分子会在随机条件下互相作用，从而形成更复杂的分子。
这个模型主要集中于早期分子的形成和演化过程。
②热液喷泉模型：该模型认为，早期地球上的生命可能是在热水喷泉的温泉中形成的。
在这里，热液提供了反应所需的能量和重要的催化活性，而这些特性可能有利于有机分子的合成和复杂化合物的形成。
人教版高一英语必修三Unit4课文翻译
⼈教版⾼⼀英语必修三Unit4课⽂翻译⼈教版⾼⼀英语必修三Unit 4课⽂翻译Unit 4 Astronomy:the science of the stars —Reading—HOW LIFE BEGAN ON THE EARTH地球上⽣命的起源No one knows exactly how the earth began, as it happened so long ago. However, according to a widely accepted theory, the universe began with a "Big Bang" that threw matter in all directions. After that, atoms began to form and combine to create stars and other bodies.没有⼈确切知道地球是怎样开始形成的，因为在很早很早以前它就形成了。
然⽽，⼀种普通为⼈们所接受的理论是：宇宙起源于⼀次⼤爆炸，这次⼤爆炸将物质投射到四⾯⼋⽅。
然后，原⼦开始形成并结合成恒星和其他天体。
For several billion years after the "Big Bang", the earth was still just a cloud of dust. What it was to become was uncertain until between 4.5 and 3.8 billion years ago when the dust settled into a solid globe. The earth became so violent that it was not clear whether the shape would last or not. It exploded loudly with fire and rock. They were in time to produce carbon, nitrogen, water vapour and other gases, which were to make the earth's atmosphere. What is even more important is that as the earth cooled down, water began to appear on its surface.⼤爆炸后好⼏⼗亿年过去了，但地球还只是⼀团尘埃。
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© 2009 SCIENTIFIC AMERICAN, INC.
September 2009
© 2009 SCIENTIFIC AMERICAN, INC.
55 SCIENTIFIC A MERIC A N
another, and eventually to turn into the lifeforms we know.
On the other hand, the paradox would disappear if the first organisms did not require proteins at all. Recent experiments suggest it would have been possible for genetic molecules similar to DNA or to its close relative RNA to form spontaneously. And because these molecules can curl up in different shapes and act as rudimentary catalysts, they may have become able to copy themselves—to reproduce—without the need for proteins. The earliest forms of life could have been simple membranes made of fatty acids—also structures known to form spontaneously—that enveloped water and these self-replicating genetic molecules. The genetic material would encode the traits that each generation handed down to the next, just as DNA does in all things that are alive today. Fortuitous mutations, appearing at random in the copying process, would then propel evolution, enabling these early cells to adapt to their environment, to compete with one
■ ■ Other studies have supported the hypothesis that primitive cells containing molecules similar to RNA could assemble spontaneously, reproduce and evolve, giving rise to all life.
Much research, therefore, has focused on understanding the possible origin of RNA. Genetic molecules such as DNA and RNA are polymers (strings of smaller molecules) made of building blocks called nucleotides. In turn, nucleotides have three distinct components: a sugar, a phosphate and a nucleobase. Nucleobases come in four types and constitute the alphabet in which the polymer encodes information. In a DNA nucleotide the nucleobase can be A, G, C or T, standing for the molecules adenine, guanine, cytosine or thymine; in the RNA alphabet the letter U, for uracil, replaces the T [see box above]. The nucleobases are nitrogen-rich compounds that bind to one another according to a simple rule; thus, A pairs with U (or T), and G pairs with C. Such base pairs form the rungs of DNA’s twisted ladder—the familiar double helix—and their exclusive pairings are crucial for faithfully copying the information so a cell can reproduce.
A cell’s protein-making process involves complex enzymes pulling apart the strands of DNA’s double helix to extract the information contained in genes (the blueprints for the proteins) and translate it into the finished product. Thus, explaining how life began entails a serious paradox: it seems that it takes proteins—as well as the information now stored in DNA—to make proteins.
■ ■ Scientists are now aiming at creating fully self-replicating artificial organisms in the lab oratory—essentially giving life a second start to understand how it could have started the first time. —The Editors
It is virtually impossible to imagine how a cell’s machines, which are mostly protein-based catalysts called enzymes, could have formed spontaneously as life first arose from nonliving matter around 3.7 billion years ago. To be sure, under the right conditions some building blocks of proteins, the amino acids, form easily from simpler chemicals, as Stanley L. Miller and Harold C. Urey of the University of Chicago discovered in pioneering experiments in the 1950s. But going from there to proteins and enzymes is a different matter.
The actual nature of the first organisms and the exact circumstances of the origin of life may be forever lost to science. But research can at least help us understand what is possible. The ultimate challenge is to construct an artificial organism that can reproduce and evolve. Creating life anew will certainly help us understand how life can start, how likely it is that it exists on other worlds and, ultimately, what life is.
Investigators have one more reason for thinking that RNA came before DNA. The RNA versions of enzymes, called ribozymes, also serve a pivotal role in modern cells. The structures that translate RNA into proteins are hybrid RNAprotein machines, and it is the RNA in them that does the catalytic work. Thus, each of our cells appears to carry in its ribosomes “fossil” evidence of a primordial RNA world.
Life on Earth BY Alonso Ricardo and Jack W. Szostak
origin of holly lindem (photoillustration); Gene Burkhardt (styling)
Key Concepts