An Enzyme Has a Total of Four Active Sites

question 52

Multiple Choice

An enzyme has a total of four active sites. When you denature the molecule and study its composition, you find that each active site occurs on a different polypeptide. Which of the following hypotheses does this observation support?

• A) The enzyme is subject to regulation.
• B) The enzyme requires a cofactor to function normally.
• C) The protein's structure is affected by temperature and pH.
• D) The protein has quaternary structure.

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Definitions:

Labour Rate Variance

The difference between the actual cost of labor and its expected cost based on standards set for production.

Labour Efficiency Variance

The difference between the actual labor hours used in production and the standard hours expected, multiplied by the standard labor rate.

Standard Costing

A cost accounting method that uses standard costs—the expected costs of labor, material, and overhead—to compare against actual costs.

Variable Overhead

encompasses the costs of production that vary with the level of output, such as utilities and materials, as opposed to fixed overheads.