Enzymes

1. State at least three characteristics of enzymes.

2. How do enzymes speed up chemical reactions? (lower activation energy)

3. What term refers to the amount of energy needed to begin a chemical reaction? (activation energy)

4. Explain how changing the pH and/or salt concentration of a solution containing an enzyme can destroy the enzyme activity. (denatures enzyme)

5. Explain how temperature can sometimes increase, sometimes decrease, and sometimes stop enzyme activity. (as temp increases molecules move faster; above optimal temp, enzyme starts to denature; too high a temp can denature enzyme completely)

6. Using an example, describe how most enzymes are named. (often the substrate or what it does with -ase ending)

7. How is it that each enzyme catalyses only one specific reaction? (shape of active site is specific)

8. Discuss the importance of enzymes to the life of a cell. (allow reactions to proceed at biological temp)

9. What is the purpose of a fever? Explain why a high fever is dangerous. (fever speeds up metabolic reactions to help combat bacteria because some bacteria are less resistant to temperature changes than human cells. High fever could denature enzymes)

10. When Siamese cats are born, their coloration is very light over their entire body. After many months, fur on their ears, paws, tail and nose darkens (these parts of the body are cooler than the rest). From what you know about the effect of temperature on enzyme activity, propose a hypothesis that might account for this phenomenon. (the enzyme that converts the pigment from light to dark is only active at the lower temperature)