In Some Cells, There Are Many Different Ion Electrochemical Gradients

question 42

Multiple Choice

In some cells, there are many different ion electrochemical gradients across the plasma membrane even though there are usually only one or two types of proton pumps present in the membrane. The gradients of the other ions are most likely established by which of the following?

• A) cotransport proteins
• B) ion channels
• C) pores in the plasma membrane
• D) passive diffusion across the plasma membrane

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Definitions:

Average Costs

The cost per unit is determined by dividing the total production cost by the number of units manufactured.

Long Run

A period sufficient for all inputs to production, including physical capital, to be adjusted.

Shut-Down

A temporary or permanent cessation of operations in a business or factory, often due to financial difficulties or external factors.

Marginal Costs

The additional cost incurred from producing one more unit of a product or service.