Figure 6

Phosphatidylserine on the extracellular face of apoptotic hydra cells (A) annexin-V-fluorescin label of a hydra cell after induction of apoptosis with colchicine, (B) phase contrast image of the cell, (C) absence of propidium iodid (PI) staining: PI can only enter cells after membrane integrity is lost, absence of PI staining indicates that annexin-V-fluorescin binds the extracellular face of the membrane.