Figure 2: Schematic presentation of the relationship between the different types of cell death. Cell death could be controlled (physiological), including autophagy (caspase-independent) and apoptosis (caspase-dependent), or necrotic. The boundaries between apoptosis, necrosis, and autophagy are not always clear. Apoptotic death is mostly caspase-dependent; however apoptotic morphology can sometimes be registered without obvious caspase activation [136]. Caspase activation can occur through membrane receptor binding (extrinsic) or as a result of metabolic changes following mitochondrial depolarisation (intrinsic) and release of cytochrome C and APAF-1 (adapted from [136]).