Comparative studies to find out the dependence of photosynthesis on chloroplast arrangement were carried out on: Lemna trisulca, Funaria hygrometrica, Mougeotia sp. and Spirogyra nitida. A specially adapted tube respirometer was constructed and with its use it was possible simultaneously with observations in 150x microscope magnification during illumination at different light intensities to measure gaseous metabolism in leaves a few mm2 in area and alga filaments a few mm long with an accuracy 10-3 [mu]l. The description of the respirometer, possible errors, and methods are given in the greatest detail. The relation between the course of photosynthesis and the chloroplast arrangement was found in weak light only, where with the movement of chloroplasts from apostrophe to epistrophe and parastrophe to epistrophe position an increase in photo-synthetic rate was found. Respiration in the dark and assimilation in strong light have a constant dependence on simultaneous changes of chloroplast arrangement. The process of assimilation and the movement from epistrophe to parastrophe position are independent of each other. Arrangement of chloroplasts influences the curve of photosynthesis and chloroplasts are in epistrophe in that part of the curve where photosynthesis rate increases proportionally to light intensity, and when light intensity has no further influence on chloroplast movement full parastrophe is reached.
Zurzycki, J. (2017). Chloroplasts arrangement as a factor in photosynthesis. Acta Societatis Botanicorum Poloniae, 24(1), 27–63. https://doi.org/10.5586/asbp.1955.003