2c - Enzymes

Catalysts

催化剂 (cuīhuàjì) Chemicals that speed up reactions without being used up themselves.

Metabolism

新陈代谢 (xīnchén dàixiè) All the chemical reactions happening in an organism.

Substrate

底物 (dǐwù) / 反应物 (fǎnyìngwù) The substance an enzyme acts on.

Active site

活性位点 (huóxìng wèidiǎn) The specific part of an enzyme where the substrate binds and the reaction happens.

Lock and key model

锁钥模型 (suǒyào móxíng) Model explaining how enzymes and substrates fit together perfectly due to their specific shapes.

Denatured

变性 (biànxìng) When an enzyme's active site changes shape (e.g., due to heat or pH), so it no longer fits its substrate.

Enzyme

酶 (méi) A biological catalyst, usually a protein, that speeds up reactions in living things.

Enzyme Specificity

酶的专一性 (méi de zhuānyīxìng) The property of an enzyme that allows it to bind to only one specific substrate (or a very limited range of substrates) due to the unique shape of its active site.

Optimum Temperature

(酶的）最适温度 ((méi de) zuìshì wēndù) The temperature at which an enzyme exhibits its highest rate of activity.

Optimum pH

（酶的）最适pH值 ((méi de) zuìshì pH zhí) The pH value at which an enzyme exhibits its highest rate of activity.