51. Triemer, R. E. and R. M. Brown, Jr.
1975. Ultrastructure of fertilization in Chlamydomonas moewusii.
Protoplasma 84:315-325.
51. Summary
The fine structure of fertilization in Chlamydomonas
moewusii has been examined. A network of endoplasmic reticulum
extending from the nucleus to an electron dense body in the anterior
papilla of the cell is described. The initial contact of gamete
cells occurs at the flagellar tips A spiralization of the paired
flagella results in the juxtapositioning of the cell bodies allowing
papillar fusion. A bridge containing fibrous material is formed
and joining the cells as a vis a vis pair. Elements of
ER extending from the nucleus project into the bridge and fuse
thereby establishing continuity between the outer nuclear membranes.
Six to eight hours after the formation of pairs, the cytoplasmic
bridge broadens and plasmogamy continues. Two to three hours
after the onset of plasmogamy the gamete nuclei approach by a
shortening of the common ER network. The outer nuclear membranes
contact, followed by contact and fusion of the inner nuclear membranes.
Nucleoli are persistent throughout fertilization and appear to
fuse following karyogamy.