ISSN:
1432-234X
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Biologie
Notizen:
Abstract Behavioral and morphogenetic responses to conjugative interactions of Aspidisca sedigita and A. steini were studied using transmission and scanning electron microscopy. The following changes related to the phenomenon of conjugation have been evidenced. Most of the potential mates show a lifting of the peristomial lip before sticking together in pairs. At the beginning of pairing, mates face each other fusing their lifted peristomial lips. The fusion involves only the mates’ plasma membranes, whereas cortical alveoli are disrupted and unconnected. The left member of the pair (B mate) soon turns through about 180°. Eventually the right ventral side of the rotating B mate overlaps the left dorsal side of the non-rotating one (A mate). Because of this rotation the fusion zone stretches and becomes like a ”tube” rather than being a simple ”door” connecting the mates. In addition to the behavioral differences, the contribution to the ”tube” formation is also different between the two partners of the mating. The B mate supplies the majority of both pellicle and cytoplasm. The dorsal surface of the A mate is partially involved. The morphogenetic pattern during the mating reaction in Aspidisca species has been analyzed and compared with that of members of related genera. It can be related to that of Euplotes species, although differences in the relative timing of the events have been observed.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/s004350050051
