| English | 意味 |
|---|---|
| enzyme/ˈenzaɪm/ | 酵素 |
| catalyst/ˈkætəlɪst/ | 触媒 |
| active site/ˈæktɪv saɪt/ | 活性部位 |
| substrate/ˈsʌbstreɪt/ | 基質 |
| activation energy/ˌæktɪˈveɪʃn ˈenədʒi/ | 活性化エネルギー |
Speeding up life's reactions
- Most reactions that keep you alive would happen far too slowly on their own.
- Digesting a meal could take years without help.
- Cells use special proteins to make these reactions fast enough.
- These proteins are enzymes — the catalysts of life.
Enzymes are catalysts
- An enzyme 酶 is a biological catalyst 催化剂.
- A catalyst speeds up a reaction without being used up itself.
- One enzyme molecule can be reused thousands of times.
- Almost every reaction in a cell has its own enzyme.
酵素とは生物学的な…
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酵素は生体触媒であり、反応を促進しながら自身は消費されません。
The active site
- Each enzyme has a pocket called the active site 活性位点.
- The substrate 底物 — the molecule it works on — fits into this pocket.
- The fit is specific, like a key in a lock.
- This is why each enzyme works on only one kind of substrate.
基質は酵素のどの部位に結合しますか？
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基質は酵素の活性部位に、鍵が錠前に入るように fit します。
Lowering the activation energy
- Every reaction needs a starting push of energy — the activation energy 活化能.
- An enzyme lowers this energy barrier.
- With a smaller barrier, the reaction happens far faster.
- It can now run quickly at the gentle temperature of a living cell.
酵素速度と基質
速度 = Vmax・[S] / (Km + [S])
基質をドラッグしてください。すべての活性部位が忙碌になるまで速度は上昇し、Vmaxで頭打ちになります。
酵素は活性化エネルギーを低下させることで反応を速めます。
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活性化エネルギーを低下させることで、酵素は体温下でより速く反応を進めさせます。
酵素に関する正しい記述をすべて選択してください。
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酵素は消耗せず再利用されます。残りの三つは正しいです。
An enzyme is not used up in the reaction. It grabs the substrate, helps it react, then lets the product go — unchanged and ready to work again. This is why a cell needs only a tiny amount of each enzyme.
酵素は消耗しないため、一つの酵素分子が何回も利用されます。
難易度 1/5 · 100 コイン + 今日初回完了時に小ボーナス付与
触媒は再利用されるため、微量の酵素でも膨大な数の基質分子を処理できます。
Catalase, an incredibly fast enzyme:
- Your cells make hydrogen peroxide, a toxic waste.
- The enzyme catalase breaks it into harmless water and oxygen.
- A single catalase molecule can handle millions of peroxide molecules every second.
An enzyme is a biological catalyst that speeds up a reaction without being used up. The substrate binds to the enzyme's active site (a specific, lock-and-key fit), and the enzyme lowers the reaction's activation energy so it runs fast at body temperature.