A cell with a flat alveolar sac system. It is not clear why some cells have expanded alveoli and others have flattened alveoli. Cacodylate buffered fixative. TEM taken on 2/3/69 by R. Allen with Phil...

This view shows a transverse ridge cut with its sloping side lying tangentially in the section plane. The granulo-fibrillar filled peaks are prominent. Striated bands appear sectioned closer to their ...

This view shows a transverse ridge cut with its sloping side lying tangentially in the section plane. The granulo-fibrillar filled peaks are prominent. Striated bands appear sectioned closer to their ...

Freeze fracture image of the surface ridges at the anterior end of the cell where kineties to the right and left sides come together at an angle at the anterior suture tip. In this area are numerous p...

Receptor mediated endocytosis is a process in which extracellular molecules are taken into the cell via coated vesicles that pinch from the plasma membrane. In Paramecium the resulting vesicles fuse w...

Cross sections of striated bands and infraciliary lattice arms. Filaments of the striated bands are less densely packed than the infraciliary lattice. Kinetodesmal fibers and postciliary microtubules ...

Septa of bordering alveoli when lying in the plane of section exhibit pores at their outer margins closest to the plasma membrane. This shows that there is physical continuity between the lumens of al...

A grazing section through the cell’s surface shows segments of six rows of cilia running across the figure sectioned superfically at the top and deeper into the cell as one progresses down the figur...

A grazing section through the cell’s surface shows segments of six rows of cilia running across the figure sectioned superfically at the top and deeper into the cell as one progresses down the figur...

A view of cross sections of the finger-like extensions of the alveoli that bind to the cytostomal cord. Alveoli store calcium (see Stelly et al., J. Cell Biol. 113:103-112, 1991) and calcium release c...