POC Conf. Call 4-12-11
POC meeting, Webex Conference Call; Date: Tuesday April 12th, 2011 10am (PDT)
In attendance:
POC members:
Absent:
Collaborators:
Acceptance of the minutes from the POC_Conf._Call_4-5-11?
Items arising from last week's meeting:
Cardinal organ parts
Terms requested by MO:
Moss Ontology definition: A membranous or hairy cap or hood that forms from the wall of the archegonium and protects the embryonic sporophyte. It is formed from the archegonium by mitotic divisions, and hence it is haploid. Bill and Nancy Malcolm (2006): Mosses and other Bryophytes, an illustrated glossary, second edition and altered from David Cove.
We also have a request (from PJ) for calyptra, which is part of the fruit in Eucalyptus. That term should be named fruit calyptra (see below under operculum), and this term should be named spore capsule calyptra, to distinguish them.
Proposed name and def.: spore capsule calyptra: A cardinal organ part that develops from the upper part of an archegonium and surrounds a sporangium.
Comment: Found in bryophytes and pteridophytes (according to Parihar). The calyptra ia a membranous or hairy cap or hood composed of gametophytic tissue that protects the embryonic sporophyte within the archegonium. In some species, the calyptra may persist after the sporophyte develops and gets carried upward as the seta elongates.
participates_in gametophytic phase, develops_from venter (more specific) or archegonium (more general)?
subsets for bryophytes, pteridophytes
This term was not suggested by Moss Ontology, but perhaps we should add it.
proposed def.: A cardinal organ part that is the enlarged basal part of an archegonium and has an egg cell located in it.
part_of archegonium
subsets for bryophytes, pteridophytes, gymnosperms
This term was not suggested by Moss Ontology, but perhaps we should add it.
proposed def.: A cardinal organ part that is the elongated apica part of an archegonium.
Comment: Early in development, the neck is occluded by a single row of neck canal cells. At maturity, the neck canal cells disintegrate, creating a canal for the sperm to enter the archegonium.
part_of archegonium
(can also add term for neck canal cell when we deal with cells)
subsets for bryophytes, pteridophytes, gymnosperms
Proposed name and def.: sporangium base: A cardinal organ part that is the basal part of a sporangium.
Comment: Term used in mosses and other bryophytes (what about pteridophytes?). The sporangium base is the sterile part of the sporangium below the theca. If swollen and distinct from the rest of the sporangium, it is called an apophysis or hypophysis. (ref: Bill and Nancy Malcolm (2006): Mosses and other Bryophytes, an illustrated glossary, second edition)
part_of sporangium; Synonyms: sporangium neck, apophysis, hypophysis
subsets for bryophytes
Moss Ontology definition: The main body (urn) of a sporangium. Altered from Bill and Nancy Malcolm (2006): Mosses and other Bryophytes, an illustrated glossary, second edition
We already have the term theca (PO:0009069) to describe paired microsporangia in angiosperms. Maybe we should call that anther theca and call this term sporangium theca:.
Proposed name and def.: sporangium theca: A cardinal organ part that is the main body of a sporangium and has spores located in it.
Comment: Term used in mosses and other bryophytes (what about pteridophytes?)
part_of sporangium
subsets for bryophytes, maybe pteridophytes
Moss Ontology definition: A single or double circle of teeth inside the mouth of a moss sporangium. Bill and Nancy Malcolm (2006): Mosses and other Bryophytes, an illustrated glossary, second edition
proposed definition: A cardinal organ part that is a single or double circle of teeth inside a spore capsule mouth.
Comment: The peristome is located under the operculum, if an operculum is present. Upon maturity of a capsule, the teeth of the peristome open to release the spores.
part_of sporangium
subsets for bryophytes
- peristome tooth
Not requested by Moss Ontology, but should add it.
Proposed def: A cardinal organ part that is a single lobe or tooth of a peristome.
Comment: Peristome teeth may be simple or compound, and may be attached by their tips to the epiphragm.
part_of peristome
subsets for bryophytes
- Add term for peristome cell? Are they dead at maturity? What kind of cells are they?
Moss Ontology definition: Either the lid that blocks the capsule mouth or the apical portion of a sporangium that opens during dehiscence. Bill and Nancy Malcolm (2006): Mosses and other Bryophytes, an illustrated glossary, second edition.
We also have a request (from PJ) for operculum, which is part of the fruit in Eucalyptus. That term should be named fruit operculum, and this term should be named spore capsule operculum, to distinguish them.
Proposed name and def.: spore capsule operculum: A cardinal organ part that is the apical part of a spore capsule that separates from the rest of the capsule during dehiscence.
Comment: Found in mosses. May remain partly attached to the rest of the capsule.
Synonym: sporangium lid
part_of sporangium
subsets for bryophytes
Also add these terms for angiosperms:
fruit operculum: A cardinal organ part that is the apical part of a capsular fruit that separates from the rest of the capsule (the fruit calyptra) during dehiscence. part_of fruit
Comment: Found in Eucalyptus.
Is is a cardinal organ part (formed from a single carpel) or collective organ part structure (formed from parts of multiple carpels)?
fruit calyptra: A cardinal organ part that is the basal part of a capsular fruit that separates from the fruit operculum during dehiscence. part_of fruit
Comment: Found in Eucalyptus. The calyptra may remain attached to the plant after the fruit operculum dehisces.
Question: is the calyptra actually the base of the fruit, or it is an enlarged hypanthium that surrounds the fruit?
Proposed definition: A plant anatomical space that is the opening on the apical end of a spore capsule.
Comment: The mouth is formed when the operculum separates from the capsule. The mouth may be covered by a peristome.
part_of sporangium
subsets for bryophytes
Schofeld says it is a "membranelike expansion of the columella covering most of the mouth of the sporangium in Polytrichidae (hair cap mosses)."
From Crum: "A circular membrane at the tip of the columella to which the peristome teeth of the prolytrichaceae are attached."
Proposed definition: A portion of parenchyma tissue that forms a circular membrane extending from a spore capsule collumella and attached to the ends of the peristome teeth that covers a spore capsule mouth.
Comment: Present in some moss species of the family Polytrichaceae.
Synonym: tympanum
subsets for bryophytes
From Crum: "An elongation of the gametophytic axis on which the capsule is borne in Sphagnum and Andreaea."
From Schofeld: "An elongated mass of leafless gametophore tissue that pushes the sporophyte beyond the perichaetial leaves (in Andreaea and Sphagnum)."
Proposed definition: A plant axis that is a leafless extension of a gametophore axis on which a spore capsule is borne.
Comment: Raises the sporophyte above the perichaetial bracts. Found in Sphagnum and Andreaea.
participates_in gametophytic phase
subsets for bryophytes
Plant Tissues
===paraphyllium=== Tiny filaments, scales or leaf-like structures scattered on the stems of some leafy bryophytes. Bill and Nancy Malcolm (2006): Mosses and other Bryophytes, an illustrated glossary, second edition (MO definition)
Crum defines them as "Small green outgrowths formed between the leaves on stems and branches of some pleurocarps (mosses that produce archegonia and sporophytes laterally, rather than on the tips of their axes) and a very few leafy liverworts."
Schofield describes paraphyllia as outgrowths of the epidermis, but he also describes leaves that way.
Moss Ontology has paraphyllium listed as a plant organ, but they do not arise from the SAM as phyllomes do.
Proposed definition: A plant organ/portion of plant tissue that is a small outgrowth from the epidermis between the leaves of a gametophore axis.
Comment: Paraphyllia are much smaller than leaves and may be filamentous, scale-like, or leaf-like. Found in pleurocarpous mosses and a few leafy liverworts.
The paraphyllia are the small, dark structures between the leaves.
midrib/costa
Moss Ontology definition: The nerve of a phyllid. Altered from Bill and Nancy Malcolm (2006)
We have term midvein (PO:0020139): The central, and usually the most prominent, vein of a leaf or leaf-like organ. [source: APWeb:Glossary] (which, by the way, should just say phyllome, instead of leaf or leaf-like organ). However, midvein is_a leaf vein, which is a portion of vascular tissue, so it cannot apply to mosses.
We should have a term that groups conductive tissue together for both vascular and non-vascular plants, kind of like we have axial cell for vascular and non-vascular conductive cells.
New child of portion of plant tissue: portion of axial tissue:
(also, we need to redefine phloem to be more like definition of xylem, and not based on function)
(need to redefine axial cell so it doesn't say vascular cell)
rhizoid
archesporium
amphithecium
endothecium
jacket layer
paraphysis
axilliary hair
tmema
Plant Cells
Terms requested by MO:
archesporial cell
apical cell
shoot apical cell
phyllid apical cell
alar cell
brachycyte
chloronema cell
caulonema cell
tmema cell
jacket layer cell
axillary hair terminal cell
axillary hair base cell
neck canal cell
side branch initial
Other terms, not requested by MO:
hyrdoid
leptoid
rhizoid initial
Sporangium and its parts
This is continued from our discussion at the POC_Conf._Call_3-8-11
