[The rate of photosynthesis of different stalk regions of Acetabularia mediterranea].

The rate of photosynthesis ((14)C-incorporation) of cell parts isolated from the stalk of the alga Acetabularia mediterranea is highest in parts derived from the tip region and lowest in parts from the basal region of the stalk (Table 1).Similar results are obtained when whole cells are used for photosynthesis and divided afterwards into tip region, basal region and middle region (Fig. 1, Table 2).There is a gradient of photosynthetic capacity within the stalk which shows a pattern similar to that demonstrated for the morphogenetic capacity of the different stalk regions.