This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
[{'content': 'Free radical scavanging system enzyme is \nSelect and explain. \nA. NADPH oxidase, B. Glutathione peroxidase, C. Endonuclease, D. Phospholipase', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Answer-B. Glutathione peroxidaseAntioxidant mechanisms1. Non-enzymatic systemAntioxidants (Vit E , Vit A, Vit C, glutathione and Cysteine)Tissue proteins (transferrin, ferritin, laetofeftifl, and ceruloplasmin).2. Enzymatic systemCatalaseSupuoxide damutase (SOD)3. Glutathione peroxidasePresent in mitochondria & cytosol.It catalyzes free radical breakdown.H2O2 + 2 G S H - G S S G + 2 H2O2OH + 2 G S H - G S S G + 2H2O', 'role': 'assistant'}]