Which ion is listed as an inorganic anion activator (cofactor)?

Which ion is listed as an inorganic anion activator (cofactor)?

• A. Chloride
• B. Magnesium
• C. Calcium
• D. Zinc

Answer: (A)

Chloride is the correct choice. An inorganic anion activator is a negatively charged inorganic ion that can serve as a cofactor in enzymatic reactions. Chloride (Cl−) carries a negative charge, so it fits the role of an inorganic anion activator. The other options are positively charged metal ions (Mg2+, Ca2+, Zn2+) which are cofactors too, but they are cations, not anions, so they don’t meet the “anion activator” description.

Chloride is the correct choice. An inorganic anion activator is a negatively charged inorganic ion that can serve as a cofactor in enzymatic reactions. Chloride (Cl−) carries a negative charge, so it fits the role of an inorganic anion activator. The other options are positively charged metal ions (Mg2+, Ca2+, Zn2+) which are cofactors too, but they are cations, not anions, so they don’t meet the “anion activator” description.