Mutations · 突变
| English | 中文 | Pinyin · 拼音 |
|---|---|---|
| mutation/mjuːˈteɪʃn/ | 突变 | tū biàn |
| substitution/ˌsʌbstɪˈtjuːʃn/ | 替换 | tì huàn |
| insertion/ɪnˈsɜːʃn/ | 插入 | chā rù |
| deletion/dɪˈliːʃn/ | 缺失 | quē shī |
| mutagen/ˈmjuːtədʒn/ | 诱变剂 | yòu biàn jì |
Mistakes in the code
- Copying billions of DNA bases is astonishingly accurate — but not perfect.
- Once in a while, a base gets changed.
- Such a change to the DNA is called a mutation.
- Mutations can be harmful, harmless, or, rarely, a lucky improvement.
密码里的错误
- 复制数十亿个 DNA 碱基精确得惊人——但不完美。
- 偶尔,一个碱基会被改变。
- 这样一个对 DNA 的改变叫做突变。
- 突变可以是有害的、无害的,或者罕见地,一次幸运的改进。
What a mutation is
- A mutation 突变 is a change in the DNA base sequence.
- Because the sequence codes for proteins, a mutation can change a protein.
- A changed protein may work differently — or not at all.
- Even a single base swapped can matter.
突变是什么
- 突变(mutation)是 DNA 碱基序列的一个改变。
- 因为序列编码蛋白质,一个突变能改变一个蛋白质。
- 一个改变了的蛋白质可能工作方式不同——或者根本不工作。
- 即使换掉单个碱基也可能有影响。
A mutation is… · 突变是……
A mutation is a change in the DNA sequence, which can change the protein a gene makes. · 突变是 DNA 序列的一个改变,它可能改变一个基因制造的蛋白质。
Types of mutation
- A substitution 替换 swaps one base for another.
- An insertion 插入 adds an extra base into the sequence.
- A deletion 缺失 removes a base.
- Insertions and deletions shift the reading frame, often disrupting the whole protein.
突变的类型
- 替换(substitution)把一个碱基换成另一个。
- 插入(insertion)在序列里加进一个额外的碱基。
- 缺失(deletion)去掉一个碱基。
- 插入和缺失会移动阅读框,常常打乱整个蛋白质。
A substitution mutation is when… · 一个替换突变是当……
A substitution swaps one base for another; insertions and deletions add or remove bases. · 替换把一个碱基换成另一个;插入和缺失增加或去掉碱基。
Effects and causes
- Many mutations have no effect at all — they are neutral.
- Some are harmful; a rare few are beneficial.
- Beneficial mutations provide the variation that drives evolution.
- A mutagen 诱变剂 — UV light, radiation, or some chemicals — raises the mutation rate.
效果与原因
- 许多突变根本没有效果——它们是中性的。
- 一些是有害的;罕见的少数是有益的。
- 有益的突变提供了驱动进化的变异。
- 诱变剂(mutagen)——紫外线、辐射或一些化学物质——提高突变率。
Helpful, harmful, or neutral? · 有益、有害,还是中性?
Sort each mutation by its effect - many do nothing, some harm, and a few help. · 按照效果给每个突变分类——许多没有作用,一些有害,少数有帮助。
A factor that increases the mutation rate, like UV light, is a . · 一个提高突变率的因素,比如紫外线,是一个。
A mutagen — UV light, radiation, or certain chemicals — makes mutations more likely. · 诱变剂——紫外线、辐射或某些化学物质——让突变更可能发生。
Some mutations are neutral or even beneficial, not just harmful. · 一些突变是中性的,甚至是有益的,不只是有害的。
Many mutations have no effect; a few are helpful — these provide the variation that drives evolution. · 许多突变没有效果;少数是有帮助的——这些提供了驱动进化的变异。
Select all · 所有 true statements about mutations. · 选出关于突变的所有正确说法。
Not every mutation is harmful — many are neutral and some are beneficial. The other three are correct. · 并非每个突变都有害——许多是中性的,一些是有益的。其余三条正确。
Not every mutation is bad. Most are neutral, some are harmful, and a rare few are beneficial — and those helpful changes are the raw material of evolution. Do not assume "mutation" always means damage.
并非每个突变都是坏的。大多数是中性的,一些是有害的,罕见的少数是有益的——而那些有帮助的改变是进化的原材料。不要以为"突变"总是意味着损害。
One base, a big difference:
- Sickle-cell disease comes from a single substitution in the haemoglobin gene.
- That one changed base makes a faulty haemoglobin, harming red blood cells.
- Yet the same allele also protects against malaria — the very same mutation can be both harmful and helpful.
一个碱基,一个大差别:
- 镰状细胞病来自血红蛋白基因里单个的替换。
- 那一个改变的碱基造出有缺陷的血红蛋白,伤害红细胞。
- 然而同样的等位基因也防御疟疾——同一个突变可以既有害又有帮助。
A mutation is a change in the DNA base sequence. Types include substitution (swap a base), insertion (add one), and deletion (remove one). Mutations can be harmful, neutral, or beneficial, and a mutagen raises their rate. Beneficial mutations supply the variation for evolution.
突变是 DNA 碱基序列的一个改变。类型包括替换(换一个碱基)、插入(加一个)和缺失(去掉一个)。突变可以是有害、中性或有益的,而诱变剂提高它们的速率。有益的突变为进化提供变异。