Membrane differentiation in the golgi complex of Micrasterias denticulata bréb. visualized by freeze-etching

Freeze-etched dictyosomes of the alga Micrasterias denticulata (Bréb.) exhibit a gradual increase in the density of particles on the membranes of successive cisternae from the forming to the maturing face. At the maturing face a drop in particle numbers can be observed in the peripheral regions of the cisternae, where fenestration and the packaging of the secretory products takes place.