Worksheet
1. Which of the following does NOT apply to an enzyme:
Inorganic
2. When an enzyme catalyzes a reaction: Substrate(s) bind in the active site
3. Which of the following would interfere most with the ability of an enzyme to catalyze a reaction? Reduced concentration of substrate available
4. Feedback mechanisms regulate the rate of enzyme activity, effectively “turning off” an enzyme in a reversible way until more product is needed. Which of the following would be most effective as a feedback mechanism? Temporary binding of a non-substrate molecule in the active site
5. Which of the following statements is accurate in describing the activity of the lactase enzyme? One lactose enzyme can catalyze many reactions
6. Look up and write in the following definitions as they apply to chemical reactions: Catabolic
7. Is the action of the enzyme illustrated in the video: catabolic & exergonic
8. Endergonic or exergonic? Is the action of lactase: Endergonic or exergonic?
9. Why is enzyme activity similar to, but not exactly like, a “Lock” and “Key”?
Small temp and ph changes will not result in the enzyme being inhibited from catalyzing its intended reaction. The occurrence of ph and temp ranges of optimum enzyme activity do no support the assumptions made by the lock and key model of ridged active site cavities.
Table 1: Record your data on the number of product molecules formed per minute obtained from the virtual lab.
# Product Molecules/minute at:
|Amount of Substrate |pH 3 |pH 5 |pH 7 |pH 9 |pH 11 |
|(Lactose) | | | | | |
|0.5 g