Yponatremia is a condition in which the sodium in the blood is too low. Uncontrolled spasms, which are sudden, involuntary contractions of muscles, are among the symptoms of hyponatremia. Why do they occur?
A.
Sodium is needed to generate an action potential.
B.
Sodium makes up most of the myelin sheath.
C.
Sodium is the signaling molecule that transmits impulses across a synapse.
D.
Sodium controls voluntary movement, and potassium controls involuntary movement.