Depending on the type of gamete produced in a gametangium, several types can be distinguished.
Female Female gametangia are most commonly called
archegonia. They produce
egg cells and are the sites for
fertilization. Archegonia are common in algae and primitive plants as well as
gymnosperms. In
flowering plants, they are replaced by the
embryo sac inside the
ovule.
Male The male gametangia are most commonly called
antheridia. They produce
sperm cells that they release for fertilization. Antheridia producing non-motile sperm (spermatia) are called
spermatangia. Some antheridia do not release their sperm. For example, the
oomycete antheridium is a
syncytium with many sperm
nuclei and fertilization occurs via fertilization tubes growing from the antheridium and making contact with the egg cells. Antheridia are common in the gametophytes in "lower" plants such as
bryophytes,
ferns,
cycads and
ginkgo. In "higher" plants such as
conifers and flowering plants, they are replaced by
pollen grains.
Isogamous In
isogamy, the gametes look alike and cannot be classified into "male" or "female." For example, in
zygomycetes, two gametangia (single
multinucleate cells at the end of
hyphae) form good contact with each other and fuse into a
zygosporangium. Inside the zygosporangium, the nuclei from each of the original two gametangia pair up. ==See also==