In Some Cells, There Are Many Ion Electrochemical Gradients Across

question 53

Multiple Choice

In some cells, there are many ion electrochemical gradients across the plasma membrane even though there are usually only one or two proton pumps present in the membrane. The gradients of the other ions are most likely accounted for by ________.

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

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Definitions:

Variable Cost Per Unit

The cost that varies with the level of output, computed on a per-unit basis.

Fixed Cost

A fixed cost is a business expense that remains constant regardless of changes in production levels or sales volumes.

Relevant Range

The span of activity or production level within which the assumptions about fixed and variable costs are valid.

Activity Changes

Refers to adjustments or variations in the level of operations or processes within an organization, often impacting costs and productivity.