Final answer:
Anti-apoptotic factors inhibit apoptosis and promote cell survival, while pro-apoptotic factors induce apoptosis and promote cell death.
Step-by-step explanation:
Anti-apoptotic and pro-apoptotic classifications are based on their effects on programmed cell death, or apoptosis. Anti-apoptotic factors inhibit apoptosis and promote cell survival, while pro-apoptotic factors induce apoptosis and promote cell death. For example, Bcl-2 is an anti-apoptotic protein that prevents the release of cytochrome C and inhibits cell death, while proteins like Bak and Bax are pro-apoptotic and promote the release of cytochrome C, initiating apoptosis.