Which of These Cannot Cross the Plasma Membrane Using Channels

question 33

Multiple Choice

Which of these cannot cross the plasma membrane using channels and carriers but must instead cross by endocytosis or exocytosis?

• A) proteins
• B) ions, such as K⁺
• C) water
• D) urea
• E) sugars, such as glucose

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Definitions:

Profitability Index

A calculation used to assess the desirability of an investment, based on its present value of future cash flows relative to its initial cost.

NPV Profile

A graph that depicts the relationship between a project's net present value (NPV) and various discount rates, helping to assess the project's risk and potential profitability.

Horizontal Axis

The x-axis in a graph or chart, representing a dependent variable in data comparison exercises.

Internal Rate

The Internal Rate of Return (IRR), a measure used to evaluate the profitability of potential investments.