Multiple choice Plants require the two metallic compounds for chlorophyll synthesis viz. Fe and Mg Cu and Ca Ca and K Mg and Ca Reveal answer Fill a bubble to check yourself A Correct answer Explanation Magnesium is the central metallic atom in the chlorophyll molecule, making it structurally essential. Iron is not part of the chlorophyll structure itself but is a critical cofactor for the enzymes that catalyze its biosynthesis.