Caspases are activated through intrinsic and extrinsic pathways. In the intrinsic pathway, mitochondria release cytochrome c, which activates caspase-9. In the extrinsic pathway, death receptors on the cell surface, such as Fas, bind to their respective ligands, resulting in the activation of caspase-8. Both pathways converge on the activation of effector caspases, which then cleave various cellular substrates to execute apoptosis.
