a localized breakdown of epithelial tissues.
lacking spines, hooks, or other hardened structures.
undulating membrane:
a region of some Mastigophora in which the surface pellicle is drawn up into a fin-like ridge by the flagellum.
unilocular hydatid:
a hydatid cyst with a thick, external cyst wall and asexually budding in internal brood capsules only.
an egg prior to the differentiation of the zygote into an embryo.
an arrangement in which one type of structure (such as genital pores) occurs consistently on one side of the body.
not yet having undergone sporulation.
uterine bell:
a funnel-shaped organ in female Acanthocephala that collects eggs floating within the body cavity and passes them posteriorly to a selector apparatus.
duct in female reproductive system used to conduct eggs towards the genital opening.