The Major Cation in Extracellular Fluid Is

question 53

Multiple Choice

The major cation in extracellular fluid is

• A) sodium.
• B) potassium.
• C) calcium.
• D) magnesium.
• E) iron.

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Definitions:

Myosin

A type of protein found in muscle tissue as a thick filament that plays a key role in muscle contraction and movement.

Sarcolemma

Plasma membrane of a muscle fiber; also forms the tubules of the T system involved in muscular contraction.

Plasma Membrane

The lipid bilayer that surrounds a cell, regulating the passage of substances in and out of the cell.

Muscle Fiber

A single muscle cell, typically long and cylindrical, which contracts to produce movement.