The body strives to maintain electroneutrality at all times, i.e. the sum of positively charged cations should equal the sum of negatively charged anions. This can be illustrated in a gamblegram which shows the most common anions and cations in plasma.
The left column reflects the most abundant cations, which is primarily sodium, followed by potassium, followed by unmeasured cations (e.g. ionized magnesium, γ-globulins).
The right column reflects the most abundant anions, which is primarily chloride, followed by bicarbonate, followed by unmeasured anions. Unmeasured anions are noncarbonic acids produced by daily protein metabolism (e.g. phosphates, citrates, hippurates; these are usually excreted by the kidneys), ionized calcium and negatively charged proteins, particularly albumin (which contributes less to the unmeasured anion total than noncarbonic acids)
