Step 1: Understanding the Concept:
Minerals and electrolytes serve as essential cofactors for numerous biochemical reactions in the human body. Metabolism refers to the chemical processes that occur within a living organism in order to maintain life.
Step 2: Detailed Explanation:
1. Magnesium (\(Mg^{2+}\)): It is an essential cofactor for over 300 enzyme systems.
2. Metabolic Role: It is critical for all reactions involving ATP (Adenosine Triphosphate). In carbohydrate metabolism, it is required for glycolysis (e.g., the hexokinase reaction). In protein metabolism, it is essential for the structural integrity of ribosomes and the synthesis of DNA, RNA, and proteins.
3. Others: Calcium is primary for bone structure and muscle contraction. Sodium and Potassium are major regulators of osmotic balance and nerve impulse conduction.
Step 3: Final Answer:
Magnesium is the primary intracellular cation acting as a catalyst for carbohydrate and protein metabolic pathways.