At cyst formation in the 'giant' unicellular green alga Acetabularia, each cyst contains a single nucleus which subsequently undergoes several rounds of mitosis prior to gamete formation. Initially the nuclei form a syncytium which separates into individual gametes. This section shows a stage in gametogenesis where the syncytium has just started to divide into uninuclear gametes, and the formation of flagella from paired centrioles is in progress. See Woodcock and Miller, 1973. Ultrastructural features of the life cycle of Acetabularia I Gametogenesis. Proptoplasma 77, 313-319.
Biological Process: Gamete generation
Cysts were fixed in glutaraldehyde, post-fixed in osmium tetroxide, epoxy embedded, and thin sections stained with aqueous uranyl acetate and lead citrate. Grids were examined with a Philips 400 TEM operated at 80KV and images recorded on film.
Author: Gayle Miller
Source: The Cell: An Image Library
