primordial
91primordial valve — (ARTHROPODA: Crustacea) In Lepadomorpha and Verrucomorpha Cirripedia, one of 5 chitinous plates of cyrpid larvae …
92primordial germ cells — Germ cells at the earliest stage of development. Since germ cells may originate in the embryo at some distance from the gonads they then have to migrate to the gonadal primordia, a process that may involve chemotaxis or, more probably, random… …
93primordial soup — noun The state of the Earths oceans at a very early time in the planets history, during the early development of multicellular organisms …
94primordial valve — Chitinous plate in Cirripedia (Lepadomorpha and Verrucomorpha) having a distinctive honeycomb appearance, developing at incipient umbones of terga, scuta and carina, during metamorphosis [Moore and McCormick, 1969]. One of 5 chitinous plates… …
95primordial aorta — either of two main vascular trunks before fusion into a single aorta in the early embryo …
96primordial costal arches — arches formed in the embryo from costal processes of the vertebrae, later developing into ribs …
97primordial germ cell — the earliest recognizable precursor in the embryo of a germ cell; these originate extragonadally but migrate early in embryonic development to the gonads. Called also gonocyte …
98primordial granulosa cells — prefollicle c s …
99primordial wandering cell — a small mononuclear cell of the embryo that arises from the mesoderm and subsequently by differentiation gives rise to wandering cells of the body …
100primordial circulation — the earliest circulation by which nutriment material and oxygen are conveyed to the embryo; called also first c …