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Related to prothallial: generative cell, Tube cell


 (prō-thăl′əs) or pro·thal·li·um (-thăl′ē-əm)
n. pl. pro·thal·li (-thăl′ī) or pro·thal·li·a (-thăl′ē-ə)
A small, flat, delicate structure produced by a germinating spore and bearing sex organs. It is the gametophyte of ferns and some other plants.

[New Latin : pro- + Greek thallos, shoot (from thallein, to sprout).]

pro·thal′li·al (-lē-əl) adj.


(prəʊˈθæləs) or


n, pl -li (-laɪ) or -lia (-lɪə)
(Botany) botany the small flat free-living gametophyte that bears the reproductive organs of ferns, horsetails, and club mosses. It is either a green disc on the soil surface or it is colourless and subterranean
[C19: from New Latin, from pro- before + Greek thallos a young shoot]
proˈthallic, proˈthallial adj


(proʊˈθæl i əm)

n., pl. -thal•li•a (-ˈθæl i ə)
the gametophyte of ferns and related plants.
[1855–60; < Greek pro- pro-2 + thallíon, diminutive of thallós young shoot; see -ium2]
pro•thal′li•al, pro•thal′lic, pro•thal′line (-ˈθæl in, -aɪn) adj.
pro•thal′loid, adj.
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References in periodicals archive ?
9-12 days after sowing, the first prothallial cell appeared, in a plane perpendicular to the rhizoid, showing abundant chloroplasts (Fig.
Quinn has made ceramic pieces that represent reproduction in three organisms--the hydra, a single-cell organism that reproduces itself; the combination of prothallial cells, generative cell, tube cell, and wings from the plant world; and the oviduct (or Fallopian tube) found in human beings.
Gravity does not appear to have an independent effect on the later events of prothallus and secondary rhizoid growth in the gametophyte, for the growth of prothallial cells follows the same direction as that of the first prothallial cell, and the growth of secondary rhizoids follows the same direction as that of the primary rhizoid, no matter how the gametophyte is oriented.
Subsequently, the prothallial cell, which was short and with abundant chloroplasts, emerged from the spores cover (Fig.
First division produces a rhizoid and a prothallial cell which cut perpendicularly (Fig.
Spore germination in Callipteris is Vittaria type, prothallial development corresponds to Adiantum-type.
To make a comparative analysis of gametophytic characteristics in the twelve Mexican species and conclude of germination is of the Vittaria-type and development pattern prothallial is of the Aspidium-type, and unicelular trichomes on margin and superficial gametophytic to yield irregular aspect are characteristics to yield unit and characteristic to genera to conform Dryopteridaceae family (sensu Moran 1995) with the exception of Didymochlaena genus.