General Parasitology and Protozoa
Protozoa with no cystic phase is:
a. Trichomonas vaginalis is a flagellate protozoan which does not have any cystic stage.
b. There is only one stage in its life cycle, trophozoite which is pear shaped, 10-30μm x 5-10μm, 4 anterior flagellae, fifth flagellum moulded as an undulating membrane. In addition, a conspicuous barb-like axostyle projects opposite the four-flagella bundle.
c. Jerky, wobbling or rotatory motility. Multiplies by binary fission
d. It causes vaginitis and urethritis. It is sexually transmitted.