sentences:  The particular protein released from the mitochondria is cytochrome c. Cytochrome "c" then binds to Apaf-1 in the cytosol and results in the activation of initiator caspase-9.The activation of the initiator caspases then initiates a downstream cascade of events that results in the induction of effector caspases that function in apoptosis.One family of proteins called IAPs plays a role in regulating cell death by inhibiting the process.