Biochemical Foundations of Human Life Activity - Volkov N.I., Nesen E.N. 2000

Biochemical Foundations of Human Life Activity
Enzymes - Biological Catalysts
Classification of Enzymes

According to the International Classification of Enzymes, which is based on the types of reactions catalyzed, all enzymes are divided into six classes (Table 8). Each Class is divided into subclasses, and each subclass into sub-subclasses. Within a sub-subclass, Each enzyme has its own serial number; therefore, every enzyme in the Enzyme Commission (EC) classification system has a four-digit numerical code written after the enzyme name. For example

TABLE 8. Main classes of enzymes

Review Questions

1. What are enzymes?

2. What is The Role of enzymes in METABOLISM and in diagnosing the functional state of the body?

3. How are enzymes named?

4. How are enzymes structured?

5. WHAT IS A cofactor and what is its role? What Cofactors do you know?

6. What is the relationship between enzymes and Vitamins?

7. What Functions do the active and allosteric sites of an enzyme perform?

8. How do Isoenzymes differ from Multiple Forms of enzymes?

9. Name the main Properties of Enzymes.

10. What does the Specificity of Enzyme Action consist of?

11. Explain the Mechanism of enzyme Action. How does an enzyme interact with a substrate?

12. How do individual environmental factors affect enzyme activity?

13. What are enzyme activators and inhibitors? Give Examples of their action on specific enzymes.

14. What classes of enzymes do you know? Describe the first class of enzymes.

15. How does Physical Exercise affect the activity and properties of enzymes?



Last update: 06/08/2026

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