The Substances in Cell Membranes That Form a Barrier to the Movement

question 83

Multiple Choice

The substances in cell membranes that form a barrier to the movement of materials across the membrane are

• A) nucleic acids.
• B) external proteins.
• C) carbohydrates.
• D) internal proteins.
• E) lipids.

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Definitions:

Productivity

The measure of how efficiently goods and services are produced, often expressed as the ratio of outputs to inputs.

Diminishing Returns

An economic principle stating that as investment in a particular area increases, the rate of profit from that investment, after a certain point, cannot continue to increase if other variables remain at a constant.

Average Total Cost (ATC)

ATC refers to the per-unit cost of production, calculated by dividing the total costs by the quantity of output produced.

Diseconomies of Scale

Increases in the firm’s per-unit costs associated with increases in firm size due to inefficiencies and monitoring problems.