The Movement of a Number of Molecules Across the Apical

question 127

Multiple Choice

The movement of a number of molecules across the apical surface of the epithelial cell by secondary transporters is coupled to the the_______gradient that is maintained by the__________ on the basolateral surface of the epithelial cell.

• A) K⁺ : K⁺ pump
• B) K⁺ : K⁺ channel
• C) Na⁺ : Na⁺ channel
• D) Ca²⁺ : Na⁺/ K⁺ pump
• E) Na⁺ : Na⁺/ K⁺ pump

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Definitions:

External Validity

The extent to which the results of a study can be generalized to other situations and to other people.

Confounding Variable

A variable that influences both the dependent and independent variables in a study, potentially misleading the results if not controlled.

Independent Variable

The variable in an experiment that is manipulated to observe its effect on a dependent variable.

Internal Validity

The extent to which a study can demonstrate a cause-and-effect relationship between variables, free from external influence.