Enzymes are:

Options

A. substances made by chemists to activate washing powders
B. catalysts found in living organisms
C. synthetic catalysts
D. very active vegetative catalysts

Answer

**Step-by-Step Text Solution:**

1. **Definition of Enzymes**: Enzymes are biological catalysts that speed up biochemical reactions in living organisms. They are primarily made of proteins.

2. **Function of Enzymes**: Enzymes increase the rate of reactions without being consumed in the process. They do not alter the final product of the reaction, similar to how a catalyst functions.

3. **Specificity and Control**: Enzymes are specific to the reactions they catalyze, meaning each enzyme typically works on a particular substrate. They also control the speed of the reaction, allowing it to occur at relatively low temperatures.

4. **Energy of Activation**: Enzymes lower the activation energy required for biochemical reactions, making it easier for these reactions to occur.

5. **Origin of the Term 'Enzyme'**: The term 'enzyme' is derived from the Greek word "enzyme," which means "in yeast." This reflects the discovery of enzymes in yeast cells and their role in catalyzing biological processes.

6. **Correct Option Identification**: Among the provided options, the correct statement about enzymes is that they are catalysts found in living organisms. Other options, such as synthetic catalysts or man-made substances, are incorrect.

7. **Conclusion**: Therefore, the correct answer is that enzymes are biological catalysts found in living organisms.

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