Figure 1.

Photoinhibition of oxygen evolution in thylakoids isolated from control bean leaves (○) and from leaves of bean plants grown in the presence of 15 μm Cu²⁺ (▵). Isolated thylakoids were illuminated at 1,000 (white symbols, dashed line) or 2,000 μmol photons m⁻² s⁻¹ (black symbols, solid line).