FIGURE 2.

Tetrahymena cytogeometry and organelle nomenclature (Cole et al., 1987). (A) A ventral view and a polar projection of a nondividing cell. Ciliary rows are depicted as lines. The OA is positioned at the anterior and the cytoproct and contractile vacuole pores at the posterior. Two ciliary rows terminate just posterior to the OA. The left‐postoral row is often used as a spatial reference (row number 1), and serves as the “stomatogenic kinety” near which the new OA forms during cell division. (B) A ventral view and a polar projection of a dividing cell. A new oral primordium (OP) forms at mid‐body, just posterior to the fission zone (FZ), and a new pair of CVPs develops just anterior to the fission zone. Ciliary rows are numbered in the polar projection. The OP, CVPs, and FZ are our principle cortical landmarks