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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 ?
Morphologically, the oocysts are spherical to ovoid and do not present a micropyle.
The cubic cells synthesize proteins which are important for the micropyle region whereas prismatic cells are involved in the secretion of substances related to the eggs adhesiveness (Rizzo et al.
A teleost egg is covered with a thick envelope called a chorion, which has a narrow pore designated as a micropyle that helps to avoid polyspermy [15].
Spermatozoa must cross some of the freshly secreted jelly to reach the micropyle of the egg for successful fertilization (von Boletzky 1989).
Identification was based on the morphological features of the oocyst and sporocysts (size, shape and presence or absence of a micropyle or polar cap or oocyst residuum) under the 100 x objective, with the aid of taxonomic keys (Soulsby, 1968; Pellerdy, 1974; Levine, 1985; Coudert, 1992).
The parenchyma cells beneath the epidermis of the ovule in the micropyle end developed into an archesporial cell in late April (Fig.
The micropyle is formed by the two integuments delimiting a narrow opening that is occluded by the nucellar beak (see Figure 4F).
Eggs had a 3-leaved micropyle and highly sculptured chorion surface, typical of Lycaenidae (Fig.
Specific cells, located near the micropyle and functioning as a valve, permit the seeds to dehydrate and enter into equilibrium in a dry environment, and do not allow the absorption of water under humid conditions (BLACK et al.
The ovule is anatropous, presenting micropyle, funicle, inner and outer integument and nucellus in both floral types.
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).