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mega- and microgametophyte #318

Open planteome-user opened 13 years ago

planteome-user commented 13 years ago

We should obsolete PO:0020092 megagametophyte and PO:0020091 microgametophyte, and create new terms that can encompass dioicous bryophyte gametophytes as well as the gametophytes in angiosperms. Embryo sac and pollen will be children of these terms, as well as archegonial megagatephyte and antheridial microgametophyte. See separate trackers for embryo sac and pollen.

Proposed definitions:

megagametophyte: A whole plant in the gametophytic phase that produces only egg cells.

Comment: Megagametophytes in bryophytes only produce egg cells, but do not develop from megaspores, because there is no heterospory in bryophytes. In some pteridophytes, megagametophytes develop from megaspores. In angiosperms, Gnetum and Weltwischia the megagametophyte is greatly reduced. The megagametophyte in angiosperms is an embryo sac.

microgametophyte: A whole plant in the gametophytic phase that produces only sperm cells.

Comment: Microgametophytes in bryophytes only produce sperm cells, but do not develop from microspores, because there is no heterospory in bryophytes. In some pteridophytes, microgametophytes develop from microspores. In seed plants the male gametophyte is reduced to a pollen grain.

archegonial megagametophyte: A megagametophyte that has as parts one or more archegonia.

Comment: Megagametophytes in bryophytes only produce egg cells, but do not develop from megaspores, because there is no heterospory in bryophytes. In some pteridophytes, megagametophytes develop from megaspores.

only_in_taxon bryophyte plus pteridophytes

antheridial microgametophyte: A microgametophyte that has as parts one or more antheridia.

comment: Microgametophytes in bryophytes only produce sperm cells, but do not develop from microspores, because there is no heterospory in bryophytes. In some pteridophytes, microgametophytes develop from microspores.

only_in_taxon bryophyte plus pteridophytes

Reported by: rlwalls2008

Original Ticket: obo/plant-ontology-po-term-requests/318

planteome-user commented 13 years ago

These changes were accepted at the POC meeting on 3-29-11.

Set tracker to pending. Will close automatically if no one comments on it.

Original comment by: rlwalls2008

planteome-user commented 11 years ago

Revised definition of microgametophyte slightly with updated term names and po ids.

microgametophyte (PO:0025280): A whole plant (PO:0000003) in the gametophyte development stage (PO:0028003) that produces only plant sperm cells (PO:0000084).

need to work on the comment: "The microgametophyte in bryophytes only produce sperm cells, but do not develop from microspores, because there is no heterospory in bryophytes. In seed plants the male gametophyte is reduced to a pollen grain."

Should refer to antheridium microgametophyte (PO:0025283)? The same comment is on that term, should be revised and moved there.

Original comment by: cooperl09