The cytopharyngeal ribbons of microtubules tend to curve into a “C” shape away from the cytopharynx but they still remain connected as a ribbon and are heavily labeled by immunogold when exposed t...

The postoral fibers are also heavily labeled by anti-b-tubulin. The cell was lightly fixed, placed in metylcellulose and frozen in liquid nitrogen. Sections were produced at -100°C before thawing and...

This group represents a serial series of sections. At the level of this section, numerous food vacuoles, only three cross sectioned cilia remain of the perioral ciliature. TEM taken on 3/12/71 by R. A...

A view of the cytopharynx and its nascent food vacuole forming region. The flattened pharyngeal vesicles that may contain monolayers or bilayers of lipids seem to be equivalent to the discoidal vesicl...

The top of the cytopharyngeal basket showing a closed cytostome where food will be engulfed. In the lab Nassula was fed Phormidium inundatum, a cyanobacterium. Ingested food is seen in food vacuoles a...

The proboscis of Didinium. While not well preserved, this image clearly shows the clockwise surface ridges that are elevated by ribbons of microtubules that are involved in supporting the buccal cavit...

The oral apparatus of Tetrahymena. The undulating membrane is composed of two rows of basal bodies but only the outer row is ciliated. Both basal bodies are fully formed but only the ciliated member h...

A view of the left side of the buccal cavity. It is covered by the plasma membrane, alveoli and a single partial layer of microtubules. Specialized cytoplasm lines the posterior end of this border. Or...

Detail of the tubular extension of the alveolus to the cytostomal cord and the whiskers that attach it to the cord. TEM taken on 4/10/74 by R. Allen with Hitachi HU11A operating at 75kV. Neg.18,500X....

The transition from 3 to 2 rows of cilia can be seen in this view of the AZM. TEM taken on 7/24/67 by R. Allen with Philips 200 operating at 60kV. Neg. 1,370X. Bar = 5µm. Standard glutaraldehyde fix...