CSSD Practice Exam 2025 – Complete Study Resource

Selenium is identified as a crucial component of the glutathione peroxidase enzyme complex. This enzyme plays a significant role in the antioxidant defense mechanism of the body, as it helps in reducing hydrogen peroxide and other peroxides, thereby protecting cells from oxidative damage. The presence of selenium is essential for the enzymatic activity of glutathione peroxidase, as it exists in the form of selenocysteine, which is incorporated into the enzyme's active site.

While the other options—Vitamin B6, Vitamin E, and Iron—are important for various physiological functions, they do not directly participate in the structure or function of glutathione peroxidase. Vitamin E is known for its antioxidant properties and as a lipid-soluble nutrient, but it does not serve as a component of this particular enzyme. Iron is essential for many enzymes and processes in the body, but it does not play a role in glutathione peroxidase activity. Vitamin B6 is important in various metabolic processes but is not involved in the antioxidant defense system in this context. Therefore, selenium stands out distinctly as the key micronutrient linked to the glutathione peroxidase enzyme complex.