Operons

question 70

Multiple Choice

Operons

• A) control the expression of constitutive genes.
• B) are subject to positive or to negative control.
• C) are not affected by mutations in the genes for repressors or inducers.
• D) occur in both prokaryotes and eukaryotes.

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Definitions:

Break-Even

The point at which total costs and total revenue are equal, meaning the business is neither making a profit nor incurring a loss.

Variable Expense

Costs that change in proportion to the activity or volume of a business, such as raw materials and sales commissions.

Fixed Expense

Costs that do not change with the level of production or sales, such as rent, salaries, and insurance premiums.

Margin of Safety

This is a financial metric that measures the difference between actual sales and the break-even point, indicating how much sales can decline before a business incurs a loss.