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': 'Which of the following cell organelle is mainly involved during apoptosis? \nSelect and explain. \nA. Nucleus, B. Mitochondria, C. Endoplasmic reticulum, D. Golgi complex', 'role': 'user'}, {'content': "Answer: B \nExplanation: Loss of mitochondrial function is seen during apoptosis. Mitochondrial membrane integrity is not maintained, causing the end of normal activity and release of cytochrome c into the cytoplasm where it activates proteolytic enzymes called caspases. The initial caspases activate a cascade of other caspases, resulting in protein degradation throughout the cell. Ref: Mescher A.L. (2010). Chapter 3. The Cell Nucleus. In A.L. Mescher (Ed), Junqueira's Basic Histology: Text & Atlas, 12e.", 'role': 'assistant'}]