Bcl-2 is

(B) Anti-apoptotic > The two main anti-apoptotic proteins are Bcl-2 and Bcl-x.> These anti-apoptotic proteins normally reside in mitochondrial membranes and the cytoplasm.> When cells are deprived of survival signals or subjected to stress, Bcl-2 and/or Bcl-x are lost from the mitochondrial membrane and are replaced by pro-apoptotic members of the family, such as Bak, Bax, and Bim. When Bcl-2/Bcl-x levels decrease, the permetability of the mitochondrial membrane increases, and several proteins that can activate the caspase cascade leak out.