Which Observation Suggested to Sutherland the Involvement of a Second

question 14

Multiple Choice

Which observation suggested to Sutherland the involvement of a second messenger in epinephrine's effect on liver cells?

• A) Enzymatic activity was proportional to the amount of calcium added to a cell-free extract.
• B) Receptor studies indicated that epinephrine was a ligand.
• C) Glycogen breakdown was observed only when epinephrine was administered to intact cells.
• D) Glycogen breakdown was observed only when epinephrine and glycogen phosphorylase were mixed.

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Definitions:

Unit Contribution Margin

The difference between the selling price of a product and its variable costs.

Fixed Costs

Expenses that do not fluctuate with changes in production level or sales volume, such as rent, salaries, and insurance.

Operating Profit

Income derived from normal business operations after subtracting operating expenses and cost of goods sold, also known as operating income.

Capacity

The maximum amount that something can contain or produce.