Question

1. what characteristics allow enzymes to function in a specific way?

a. enzymes are complex compounds composed of starch
b. each enzyme has a characteristic shape
c. enzymes are long complex fats
d. each enzyme is made up of many subunits

1. a student completed a series of experiments and found that a protein - digesting enzyme (intestinal protease) functions best when the ph is 8.0 and the temperature is 37 degrees celsius. during an experiment, the student used some of the procedures listed below

• adding more protease
• adding more protein
• decreasing the ph to 6.0
• increasing the temperature to 45 degrees celsius
• decreasing the amount of light

which procedure would have the least effect on the rate of protein digestion?
a. procedure a
b. procedure e
c. procedure c
d. procedure d

Explanation:

For question 8: Enzymes are proteins. The lock - and - key model (now updated to the induced - fit model) explains enzyme - substrate interaction. The characteristic shape of an enzyme (its active site shape) allows it to bind to specific substrates. Enzymes are not made of starch (a carbohydrate) or fats (lipids). While enzymes are made of subunits (amino acids), it is the overall shape that is crucial for specific function.
For question 9: Enzyme activity is affected by substrate concentration (adding more protein can increase reaction rate if enzyme is not saturated), enzyme concentration (adding more protease can increase reaction rate if substrate is available), pH (optimal pH is 8.0, changing to 6.0 will affect activity as it is away from the optimal), temperature (optimal is 37°C, increasing to 45°C may denature the enzyme). Light has no known direct effect on the activity of this protein - digesting enzyme (intestinal protease).

Answer:

1. B. Each enzyme has a characteristic shape
2. B. Procedure E