Review Question - QID 106779

A pathologist is investigating the cytology of cells that have been infected with a particularly virulent strain of the influenza virus. The physician suspects that the virus results in cell death after viral replication in order to expedite the spread of the virus. She recalls that there are three known biochemical mechanisms of initiating programmed cellular death: 1) transmembrane receptor-mediated interaction, 2) stimuli producing intracellular signals leading to mitochondrial-initiated events, and 3) release of cytoplasmic granules into a cell via a perforin molecule. Which of the following biochemical components plays a common role in all of these 3 processes?