Define enzyme and describe their characteristics and specifications.

An enzyme is a biological catalyst, usually a protein, that speeds up the rate of a specific biochemical reaction by lowering the activation energy. Enzymes are highly specific for their substrates, meaning they catalyze only one type of reaction or work on one specific substrate. Their characteristics include:

Specificity: Each enzyme works on a specific substrate, which fits the enzyme’s active site like a key fitting into a lock.

Efficiency: Enzymes can accelerate reactions by millions of times, making them crucial for regulating metabolic pathways.

Reusability: Enzymes are not consumed in reactions, so they can catalyze many reaction cycles.

Sensitivity to conditions: Enzyme activity can be affected by temperature, pH, and substrate concentration.

Regulation: Enzyme activity can be modulated by activators or inhibitors to control metabolic processes.

Related Questions:

  1. What is the energy of activation? Explain with reference to enzyme.
  2. What happens to enzymes when you increase or decrease: (a) Temperature (b) pH (c) Substrate concentration?
  3. Only the related key can open the lock. How is this fact true for enzymes? Explain with examples.
  4. Describe the structure and uses of ATP.
  5. Describe and sketch light reactions of photosynthesis.
  6. Describe and sketch dark reactions of photosynthesis?
  7. Explain the factors affecting the rate of photosynthesis.
  8. Compare respiration and photosynthesis with examples.
  9. What are the advantages and significance of anaerobic respiration and fermentation in your daily life?
  10. Define enzyme and describe their characteristics and specifications.
  11. Describe and explain the process of aerobic respiration.
  12. Describe the structure and uses of ATP.
  13. Why are enzymes called biological catalysts?
  14. Name the factors affecting enzyme activity. At what pH do pepsin and trypsin enzymes act the best?
  15. What happens to an enzyme when it is frozen below 0°C?
  16. What happens when a protein-digesting enzyme functions in an acidic medium?
  17. How does an enzyme lower the activation energy?
  18. Why are enzymes specific and why can’t each one speed up many different reactions?
  19. Why is a small quantity of enzyme enough for catalyzing a large number of substrate molecules into products?
  20. According to the induced fit model, the active site is flexible. Does it mean that any substrate can attach to this flexible active site? If not, then explain.