Apoptosis

Apoptosis = [blank_start]programmed[blank_end] cell death Necrosis = [blank_start]unregulated[blank_end] cell death due to injury  Energy-dependent  Only affects necessary cells  Membrane [blank_start]blebs[blank_end] (bubbles form)  [blank_start]Chromatin[blank_end] condenses  Blebs bud off to break cell up into [blank_start]apoptoticbodies[blank_end]  Fragments digested by [blank_start]phagocyte[blank_end]  [blank_start]Intrinsic[blank_end] (mitochondrial) pathway: removal of growth factors/hormones leads to cascade through mitochondrion, eventually producing [blank_start]caspases[blank_end] (protease enzymes) that disintegrate the [blank_start]DNA[blank_end] and cytoskeleton to cause blebbing  [blank_start]Extrinsic[blank_end] (death-receptor mediated) pathway: [blank_start]Fas[blank_end] death ligand binds to surface receptor to initiate protein cascade that produces caspases Apoptosis is used in physiological development and [blank_start]homeostasis[blank_end]; if cells ordinarily divide, old ones may need to be destroyed