Gametophores are prominent structures in

seedless plants A cryptogam (scientific name Cryptogamae) is a plant (in the wide sense of the word) or a plant-like organism that reproduces by spores, without flowers or seeds. The name ''Cryptogamae'' () means "hidden reproduction", referring to the fac ...

on which the reproductive organs are borne. The word gametophore and ‘-phore’ (Greek Φορά, "to be carried").Bryological Glossary
/ref> In

moss Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophyta (, ) '' sensu stricto''. Bryophyta (''sensu lato'', Schimp. 1879) may also refer to the parent group bryophytes, which comprise liverworts, mosses, and hor ...

es,

liverworts The Marchantiophyta () are a division of non-vascular land plants commonly referred to as hepatics or liverworts. Like mosses and hornworts, they have a gametophyte-dominant life cycle, in which cells of the plant carry only a single set of ge ...

and

fern A fern (Polypodiopsida or Polypodiophyta ) is a member of a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. The polypodiophytes include all living pteridophytes except t ...

s (Archegoniata), the gametophores support

gametangia A gametangium (plural: gametangia) is an organ or cell in which gametes are produced that is found in many multicellular protists, algae, fungi, and the gametophytes of plants. In contrast to gametogenesis in animals, a gametangium is a haploid st ...

(sex organs, female

archegonia An archegonium (pl: archegonia), from the ancient Greek ''ἀρχή'' ("beginning") and ''γόνος'' ("offspring"), is a multicellular structure or organ of the gametophyte phase of certain plants, producing and containing the ovum or female ga ...

and male

antheridia An antheridium is a haploid structure or organ producing and containing male gametes (called ''antherozoids'' or sperm). The plural form is antheridia, and a structure containing one or more antheridia is called an androecium. Androecium is also t ...

). If both archegonia and antheridia occur on the same plant, it is called

monoecious Monoecy (; adj. monoecious ) is a sexual system in seed plants where separate male and female cones or flowers are present on the same plant. It is a monomorphic sexual system alongside gynomonoecy, andromonoecy and trimonoecy. Monoecy is conne ...

. If there are separate female and male plants they are called dioecous. In

Bryopsida The Bryopsida constitute the largest class of mosses, containing 95% of all moss species. It consists of approximately 11,500 species, common throughout the whole world. The group is distinguished by having spore capsules with teeth that are '' ...

the leafy moss plant (q. v. "

Thallus Thallus (plural: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. Many of these organisms wer ...

") is the

haploid Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respectively ...

gametophyte A gametophyte () is one of the two alternation of generations, alternating multicellular organism, multicellular phases in the life cycles of plants and algae. It is a haploid multicellular organism that develops from a haploid spore that has on ...

. It grows from its juvenile form, the

protonema A protonema (plural: protonemata) is a thread-like chain of cells that forms the earliest stage of development of the gametophyte (the haploid phase) in the life cycle of mosses. When a moss first grows from a spore, it starts as a ''germ tube'', ...

, under the influence of

phytohormones Plant hormone (or phytohormones) are signal molecules, produced within plants, that occur in extremely low concentrations. Plant hormones control all aspects of plant growth and development, from embryogenesis, the regulation of organ size, pa ...

(mainly

cytokinins Cytokinins (CK) are a class of plant hormones that promote cell division, or cytokinesis, in plant roots and shoots. They are involved primarily in cell growth and differentiation, but also affect apical dominance, axillary bud growth, and lea ...

). Whereas the

filamentous The word filament, which is descended from Latin ''filum'' meaning " thread", is used in English for a variety of thread-like structures, including: Astronomy * Galaxy filament, the largest known cosmic structures in the universe * Solar filament ...

protonema grows by

apical Apical means "pertaining to an apex". It may refer to: *Apical ancestor, refers to the last common ancestor of an entire group, such as a species (biology) or a clan (anthropology) *Apical (anatomy), an anatomical term of location for features loc ...

cell division, the gametophyte grows by division of three-faced apical cells.

References

Plant morphology {{botany-stub

See also

References