Origins of Life on Earth · 地球生命的起源
| English | 中文 | Pinyin · 拼音 |
|---|---|---|
| organic molecules/ɔːˈɡænɪk ˈmɒlɪkjuːlz/ | 有机分子 | yǒu jī fèn zǐ |
Where did the first life come from?
- Natural selection explains how life changed — but not how it first began.
- The earliest cells appeared on Earth billions of years ago.
- Before them, there was only chemistry, no biology.
- How that chemistry became the first living cell is one of science's great questions.
最早的生命从哪里来?
- 自然选择解释了生命如何改变——但不解释它最初如何开始。
- 最早的细胞在数十亿年前出现在地球上。
- 在它们之前,只有化学,没有生物。
- 那些化学如何变成第一个活细胞,是科学最大的问题之一。
A very different young Earth
- Early Earth was hot, with volcanoes, lightning, and no free oxygen.
- Its air held simple gases, and its surface held water.
- These provided the ingredients and the energy for reactions.
- The stage was set for chemistry to become complex.
一个非常不同的年轻地球
- 早期地球炽热,有火山、闪电,没有游离氧。
- 它的空气含有简单的气体,它的表面有水。
- 这些提供了反应的原料和能量。
- 舞台已经搭好,让化学变得复杂。
What did early Earth provide that could drive chemical reactions? · 早期地球提供了什么能驱动化学反应的东西?
Early Earth had energy from lightning, volcanoes, and sunlight — but little free oxygen and no life yet. · 早期地球有来自闪电、火山和阳光的能量——但几乎没有游离氧,也还没有生命。
Building organic molecules
- Given energy, simple gases can react to form small organic molecules 有机分子.
- The famous Miller-Urey experiment showed this in the lab, making amino acids.
- Over time, these small molecules could join into larger polymers, including RNA.
- Step by step, the chemistry grew more life-like.
构建有机分子
- 给予能量,简单的气体能反应形成小的有机分子(organic molecules)。
- 著名的米勒-尤里实验在实验室里展示了这一点,制造出氨基酸。
- 随时间,这些小分子能连成更大的聚合物,包括 RNA。
- 一步一步,化学变得越来越像生命。
From chemistry to the first cell · 从化学到第一个细胞
Step through how simple chemicals on early Earth may have built up into the first living cells. · 一步步走过早期地球上简单的化学物质如何可能积累成最早的活细胞。
The Miller-Urey experiment showed that early-Earth conditions could form… · 米勒-尤里实验表明,早期地球的条件能形成……
Miller and Urey made organic molecules (amino acids) from simple gases and energy — a key first step. · 米勒和尤里用简单的气体和能量制造出了有机分子(氨基酸)——关键的第一步。
The first cells
- Molecules that could copy themselves had a huge advantage.
- Wrapped inside simple membranes, they formed the first cell-like structures.
- Once such a structure could copy itself, life — and natural selection — could begin.
- From that first cell, all of today's diversity slowly branched out.
最早的细胞
- 能复制自己的分子有巨大的优势。
- 被包进简单的膜里,它们形成了最早的类细胞结构。
- 一旦这样一个结构能复制自己,生命——和自然选择——就能开始。
- 从那第一个细胞,今天所有的多样性慢慢分叉出来。
Life is thought to have built up gradually: small molecules, then polymers, then cells. · 生命被认为是逐步积累起来的:小分子,然后聚合物,然后细胞。
The steps build up: simple molecules, then larger polymers, then membrane-enclosed self-copying cells. · 这些步骤逐步积累:简单的分子,然后更大的聚合物,然后被膜包住、能自我复制的细胞。
Once the first cells existed, the diversity of life arose through natural ____. · 一旦最早的细胞存在,生命的多样性通过自然____产生。
The origin of the first · 第一个 cell is separate from natural selection, which then produced all later diversity. · 第一个细胞的起源与自然选择是分开的,自然选择随后产生了后来所有的多样性。
Select all · 所有 true statements about the origin of life. · 选出关于生命起源的所有正确说法。
Life is thought to have built up gradually, not appeared instantly. The other three are correct. · 生命被认为是逐步积累的,而不是瞬间出现的。其余三条正确。
This lesson is about the origin of the first life — a chemistry question. It is separate from natural selection, which explains the diversity of life after the first cell existed. Do not use "evolution" to mean the origin of life itself.
这一课讲的是第一个生命的起源——一个化学问题。它与自然选择是分开的,自然选择解释的是第一个细胞存在之后生命的多样性。不要用"进化"来指生命本身的起源。
The Miller-Urey experiment:
- In 1953, scientists sealed simple gases and water in a flask and added sparks (like lightning).
- After days, the flask contained amino acids — the building blocks of proteins.
- It showed that life's ingredients can form from non-living chemistry, given energy.
米勒-尤里实验:
- 1953 年,科学家把简单的气体和水密封在一个烧瓶里,加上电火花(像闪电)。
- 几天后,烧瓶里含有氨基酸——蛋白质的构建单元。
- 它表明:给予能量,生命的原料能从非生命的化学中形成。
The origin of life asks how the first cell arose from chemistry. On early Earth, energy drove simple gases to form organic molecules (shown by Miller-Urey), which built up into polymers and eventually membrane-enclosed, self-copying cells. This is a separate question from natural selection, which then produced all later diversity.
生命的起源问的是第一个细胞如何从化学中产生。在早期地球上,能量驱动简单的气体形成有机分子(由米勒-尤里展示),它们积累成聚合物,最终形成被膜包住、能自我复制的细胞。这是与自然选择分开的问题,自然选择随后产生了后来所有的多样性。