What is the Primary Anion of the ECF

Question

What is the primary anion of the ECF
A)bicarbonate ion
B)chloride ion
C)sodium ion
D)potassium ion

Accepted Answer

The primary anion of the extracellular fluid (ECF) is chloride ion. Chloride ions are negatively charged and balanced out by the positively charged sodium ions present in the ECF. Bicarbonate ion is also present in the ECF, but it is not the primary anion. Sodium ion and potassium ion are not anions but rather cations, and they also do not serve as the primary anions of the ECF.