Final answer:
Intrinsic apoptotic stimuli lead to the activation of proapoptotic Bcl-2 family proteins and the release of cytochrome C, which ultimately results in the conversion of procaspases to active caspases, inducing apoptosis.
Step-by-step explanation:
Intrinsic apoptotic stimuli cause the aggregation and activation of proapoptotic Bcl-2 family proteins. These include proteins like Bax and Bak which, when activated, lead to mitochondrial outer membrane permeabilization (MOMP). Following MOMP, cytochrome C is released into the cytosol where it binds to adaptor proteins, forming a complex that triggers the conversion of procaspases to active caspases. These caspases then initiate a cascade that results in the controlled auto-digestion of the cell.
Caspases, as proteolytic enzymes, play an essential role in dismantling the cellular components during apoptosis. The activation of caspases is a hallmark of the intrinsic pathway of apoptosis, displaying the cell's inherent capacity to self-destruct in response to internal damage or stress signals. The process of apoptosis is crucial for maintaining homeostasis and preventing the proliferation of damaged or abnormal cells.