The features of apoptotic dose responses typically have been evaluated over
a broad dose-response continuum to differentiate apoptotic and necrotic re
sponses. The present article specifically addresses the dose-response relat
ionship for apoptosis in detail. It was determined that a number of well-do
cumented cases exist in which the dose-response relationship for apoptosis
is biphasic. The underlying mechanisms and biomedical implications of this
biphasic dose-response phenomenon are discussed.