Changes in the intensity of the electron spin resonance signal of divalent manganese were found to occur in suspensions of wild-type Chlamydomonas reinhardi. The observed manganese signal decreased in the light and increased in the dark. Through the use of a continuous-flow system it was possible to determine that the manganous ions responsible for the observed signal were localized solely in t...

THE cause of many cases of uveitis is unknown and it therefore seemed useful to examine a technique, little used in ophthalmic pathology, which might help to solve some problems. This method is the antigen-antibody technique of Coons and Kaplan (1950), who coupled fluorescein isocyanate to an antiserum with which they then treated fresh frozen sections of tissue. The site of the antigen-antibod...

Illumination of intact Bryopsis corticulans chloroplasts under anaerobic conditions induced a decline of chlorophyll fluorescence and photoinhibition of Photosystems I and II. The time course of the light-induced decline of chlorophyll fluorescence and the decreases of activities of reactions sensitized by Photosystems I and II were compared. Photosystem I activity decreased in parallel with th...