Fig. 2

Basal Body and axoneme structures in Plasmodium, Toxoplasma, and Sarcocystis. a Serial transverse sections of the developing axoneme of a P. falciparum microgamete. From left to right: a basal body made of singlet microtubules, and embedded in an electron-dense mass and the distal flagellar region made of a 9+2 microtubule arrangement, can be observed. Reproduced from Fig. 1f in [16] with permission. b Transverse section through the pole (P) of a developing T. gondii microgamete. Several organelles are visible including a basal body (B) and the nucleus (N). c Longitudinal section through a T. gondii microgamete where one flagellum and its originating basal body (B) are visible. d Longitudinal section through a T. gondii microgamete where two flagella, and their originating basal bodies (B), are visible. b–d Reproduced from Fig. 2a, b, and d in [17], respectively. e Longitudinal section through the anterior portion of a T. gondii microgamete showing the position of the basal body (B) and flagella (FL) enclosed by a unit membrane (UM). Reproduced from Fig. 25 in [21]. f Transverse section through a basal body of a Sarcocystis suihominis microgamete, a coccidian parasite closely related to T. gondii, showing some microtubules doublets and triplets (arrow, B). g Transverse section through two flagellar axonemes (arrow, F) of S. suihominis. f, g Reproduced from Figs. 9 and 10 from [23], respectively