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Related to micropyle: embryo sac, synergid, antipodal cells


1. Botany A minute opening in the ovule of a seed plant through which the pollen tube usually enters.
2. Zoology A pore in the membrane covering the ovum of some animals through which a spermatozoon can enter.

[micro- + Greek pulē, gate.]

mi′cro·py′lar adj.


1. (Botany) a small opening in the integuments of a plant ovule through which the male gametes pass
2. (Zoology) a small pore in the shell of an insect's eggs through which the sperm passes
[C19: from micro- + Greek pulē gate]
ˌmicroˈpylar adj


(ˈmaɪ krəˌpaɪl)

1. the surface of the membrane through which sperm is transported to the ovum in fertilization.
2. the opening in a seed plant ovule through which the pollen tube reaches the embryo.
[1815–25; micro- + Greek pýlē gate]
mi`cro•py′lar, adj.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.micropyle - minute opening in the wall of an ovule through which the pollen tube entersmicropyle - minute opening in the wall of an ovule through which the pollen tube enters
aperture - a natural opening in something
ovule - a small body that contains the female germ cell of a plant; develops into a seed after fertilization
References in periodicals archive ?
The pollen tube enters the opening of the ovule, the micropyle, and reaches the interior of the ovule to undergo spenn release and fertilization (Endress, 1996).
6C) with one arched dorsal expansion, perforated by a large number of aeropyles (Ae) overlying the subterminal micropyle (My).
In form, the seed is oval and much closer towards the micropyle [40].
On its way, the pollen tube penetrates the stigmatic surface, is then guided through the stigma and style and placenta, grows onto the funiculus, and finally enters the micropyle of the ovule for double fertilization (Figures 1 and 3A).
Butterfly eggs These eggs can be things of beauty, with ribbing and fluting pointing the eye toward a little opening called the micropyle.
Morphological information did not extend to the micropyle, ridge pattern or filaments on the ova or eggs.
Through division of the cells in the micropylar end of the nucellus, a cell proliferation is developed that extends beyond the micropyle (Figure 6A).
9 [micro]m diameter) that has a fairly conspicuous opening or micropyle to enable sperm penetration.
In teleosts, the only common aspect is the absence of an acrosome, which has been related to the presence of a micropyle in the egg (Riehl, 1997).
General egg sculpture disappears in the side where micropyle takes place (Fig.
Sperm enters the egg through the micropyle, a small opening in the chorion.
57) oblong, bearing conspicuous micropyle at narrow end, opposite end is papillose; seed coat thick, woody, comprising nearly 20--25% of the diameter of the seed; empty individuals are dark brown to black in color, some specimens are reddish in color due to the reflectance of white endosperm within the seed; examination of endosperm from seeds shows cells intact; embryo present (Fig.