Nerve Cells Send Electrical Signals by Pumping Ions Across the Cell

question 58

Multiple Choice

Nerve cells send electrical signals by pumping ions across the cell membrane. What prevents the ions from freely flowing across the membrane?

• A) ion channels
• B) nonpolar interior of the phospholipid bilayer
• C) They bind to the polar ends of the phospholipid bilayer.
• D) Water only exists on the interior of the cell.

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