Question

If a man is exposed to an environment of 100% oxygen, then the concentration of which of the following enzyme is increased in lungs?

• A. Superoxide dismutase
• B. Catalase
• C. Carbonic anhydrase
• D. All of the above

Answer 1

The correct option is A Superoxide dismutase

Superoxide dismutases are protective enzymes and protect body against oxidative damage. Superoxide dismutases alternately catalyze the dismutation (or partitioning) of the toxic superoxide (O${}_2$) radical into either ordinary molecular oxygen (O${}_2$) or hydrogen peroxide (H${}_2$O${}_2$). Superoxide is produced as a by-product of oxygen metabolism and causes many types of cell damage. Hydrogen peroxide is also damaging, but less, and is degraded by other enzymes, such as catalase. Thus, SOD is an important antioxidant defense in nearly all living cells exposed to oxygen.

So, the correct answer is option A.