Final answer:
In apoptosis via the intrinsic pathway, Bak and Bax proteins aggregate to form pores in the mitochondrial outer membrane, releasing cytochrome c, which activates caspases that then mediate cell death.
Step-by-step explanation:
In the intrinsic pathway to apoptosis, Bak and Bax proteins aggregate and form pores across the mitochondrial outer membrane, allowing the release of cytochrome c from the intermembrane space. Once in the cytosol, cytochrome c can bind to adaptor proteins, which aggregate to form a complex with a high affinity for procaspase.
The interaction of procaspase with this complex causes a change in the procaspase, activating it into an enzyme known as caspase. These caspsases are proteolytic enzymes crucial for the execution phase of apoptosis; they begin the auto-digestion of the cell. Proteins like Bak and Bax are essential factors in controlling the cell’s fate by regulating the cytochrome c release, which triggers the apoptosis cascade.