Fig. 4

Structure of flagellar transition zone and root system in M. ovata (a) and Salpingoeca sp. (b, c). a, b Longitudinal section of flagellar apparatus with FB (fk) and NFB (nfk) having orthogonal orientation. c Transversal section of flagellar transition zone and microvilli of the collar. cf central filament, fa bandle of f-actin inside microvillus, fbr fibrillar bridge interconnecting basal bodies, fk flagellar basal body, mtoc electron dense ring around the FB (fk), producing radial root microtubules, nfk non-flagellar basal body, tp transversal plate. a after: [11]. Scale bar 500 nm