oogonium

Any of the cells that give rise through mitosis to the oocytes and are found in the ovaries of vertebrates.

A female reproductive structure in certain thallophytes and in oomycetes, usually a rounded cell or sac containing one or more oospheres.

In zoology: The primordial mother-cell which gives rise to the ovum and its follicle.

One of the youngest ovarian cells, characterized by having in its nucleus the same number of chromosomes as in the nuclei of the somatic or body-cells. The oögonia, which eventually give rise to the primary oöcytes, are homologous in the oögenesis with the spermatogonia in the spermatogenesis of the male animal of the same species.

In botany, the female sexual organ in certain cryptogamic plants.

A special cell in certain cryptogamous plants containing oöspheres, as in the rockweeds (Fucus), and the orders Vaucherieæ and Peronosporeæ.

An immature ovarian egg within a developing fetus