Cells Can Increase Their Responsiveness to an External Chemical Regulator

question 25

Multiple Choice

Cells can increase their responsiveness to an external chemical regulator by

• A) increasing the number of their transmembrane receptors by exocytosis.
• B) decreasing the number of their transmembrane receptors by endocytosis.
• C) uncoupling their receptors from the second message generator.
• D) increasing the number of their transmembrane receptors by endocytosis.
• E) mutating their extracellular receptors so that the affinity for the chemical regulator is reduced.

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Definitions:

Contribution Margin Ratio

A financial metric that measures the proportion of revenue that exceeds variable costs, indicating how much of sales revenue is available to cover fixed costs and generate profit.

Fixed Costs

Costs that remain constant regardless of the amount of output or the level of business operations, including expenses like rent, wages, and insurance fees.

Rent Expense

The cost incurred from renting property or equipment for business or personal use, recognized as an expense on the income statement.

Margin of Safety

The difference between actual sales and the break-even point, used as a buffer against unpredictability in business performance.