Whereas Sodium Is Found Mainly in the Extracellular Fluid,most ________

question 33

Multiple Choice

Whereas sodium is found mainly in the extracellular fluid,most ________ is found in the intracellular fluid.

• A) potassium
• B) chloride
• C) bicarbonate
• D) iron

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Definitions:

Plasma Membrane

The biological membrane that separates the interior of all cells from the outside environment, protecting the cell and controlling movement of substances in and out.

Hydrophobic Region

A part of a molecule that is repelled by water and tends to be nonpolar.

Phospholipids

A class of lipids that are a major component of all cell membranes, essential for cellular function.

Polar (Hydrophilic) Region

A part of a molecule that has a tendency to interact with water through hydrogen bonding or electrostatic interaction, making it soluble in water.