The number of thylakoids per granum, which is smaller in sun-type chloroplasts than in shade-type chloroplasts, was counted for the chloroplasts at various positions within the single leaves of Spinacia oleracea L. and Glycine max (L.) Merrill. The thylakoid number increased with depth from the adaxial surface, but this trend was not evident within respective cells. Therefore, photosynthetic properties of chloroplasts should be similar within a cell but different among cell layers. The similarity within a cell may be due to the nuclear control of the chloroplast development and/or to chloroplast movement along the cell walls. Illumination of the leaves of G. max from the abaxial side during their expansion resulted in the complete inversion of the intra-leaf gradient in the thylakoid number, indicating that the formation of the intra-leaf gradient in chloroplast properties is influenced by the intra-leaf light environment during the later phase of leaf development.
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Terashima et al. (1986) studied this question.