Abstract
Whole chloroplasts isolated from the leaves of spinach (Spinacia oleracea L.) exhibit 2 types of conformational change during electron transport. Amine-uncoupled chloroplasts swell and atebrin-uncoupled chloroplasts shrink. Chloroplasts uncoupled by carbonylcyanide phenylhydrazones and by treatment with ethylenediamine tetraacetic acid do not change their volumes or light-scattering properties during electron transport. Phosphorylating chloroplasts shrink only slightly.