The cytopharynx in cross section showing the cytopharyngeal microtubular ribbons lying in the plane of the section. Some discoidal vesicles, some containing HRP label, are also seen in planar view. Ac...

One important function of the filamentous reticulum is to provide for the anchorage of cytopharyngeal microtubular ribbons along the left lip of the cytopharynx. This micrograph shows two ribbons aris...

One segment of the assembly line used for phagosome membrane growth in P. caudatum. Cytopharyngeal ribbons bring discoidal vesicles to the left lip of the cytopharynx where the vesicles bind and then ...

Detail of the origin of the cytopharyngeal microtubules along the left side of the cytopharynx that arise within the filamentous reticulum in contact with its electron-opaque nodes. This system does n...

The cytoproct is the cell’s defecation site where spent digestive vacuoles fuse with the plasma membrane. In this cell the cytoproct is closed and forms a ridge along the posterior suture on the ven...

Kinetodesmal fibers arise from the proximal ends of the basal bodies and curve upward and to the cell’s right of the kinety. Together with kds arising from more posterior basal bodies they form a st...

Stacks of 4 or 5 kinetodesmal fibers occupy the longitudinal ridges in a cross-sectioned cell. The kds lie along the right side of each ridge (cell’s left side), and as the kds are tapered, the smal...

Except that the nuclear envelope remains intact, micronuclear mitosis occurs in a normal way passing through the four stages of prophase, metaphase, anaphase and telophase. In this example a micronucl...

During self conjugation two cells from a 6-day old culture come together, bridges are formed between them and haploid products of meiotic division of their micronuclei are exchanged between the mating...

Occasionally mitochondria of Paramecium become filled with cristae that display a wavy or helical pattern. In thin sections these cristae are viewed as curved arcs as well as cross sectioned rows in d...