This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General physiology, Subject name: Physiology
In apoptosis which is/are involved 
Select and explain. 
A. Apaf-1, B. Bcl2, C. Caspases, D. Programeed cell death
A: Apaf-1
Answer: A: Apaf-1 
Explanation: Cytochrome c is a component of the electron transpo chain in mitochondria. ... Cytochrome c is also involved in initiation of apoptosis. Upon release ofcytochrome c to the cytoplasm, the protein bindsapoptotic protease activating factor-1 (Apaf-1).which is very impoant for cellular apoptosis Ref guyton and hall textbook of medical physiology 12/e pg 40