When mitochondria are damaged, this is released into the body of a cell, and its release from a cell is often indicative of apoptosis.  
When mitochondria are damaged, this is released into the body of a cell, and its release from a cell is often indicative of apoptosis.  Some molecules that perform analogous functions use azurin or ferredoxin, but its prosthetic group consists of a heme group with an iron ion inside.  Attaching electrons to oxygen molecules before they are combined with hydrogen, this is, for 10 points, what molecule found near the end of the electron transport chain?
When mitochondria are damaged, this is released into the body of a cell, and its release from a cell is often indicative of apoptosis.  
cytochrome c oxidase