A DEEP-ETCH STUDY OF THE CYTOSKELETON OF GIARDIA-DUODENALIS

The quick-freeze, freeze-fracture, deep-etching and rotary replication techniques were used to analyze the structural organization of Giardi a duodenalis. The surface of the flagella was rugous, in contrast to t he cell body surface which was smooth. The ventral region was characte rized in more detail, exposing the layer of sub-pellicular microtubule s bonded to the microribbon sheet which appears as an open flat helico id structure where the two free ends overlap and adhere close to the f rontal part of the protozoan. The microribbon appears as 18-nm thick p arallel (35 nm interval) filaments connected by short bridges. A flatt ened structure with a highly organized array of particles was seen clo se to the microribbons.