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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.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


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
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(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.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
In the pre-ovulatory phase, germinal vesicle migration towards the micropyle was detected in most oocytes.
The seeds underwent an asepsis process according to Brasil (2013) and were subjected to the treatments of dormancy overcoming, in a completely randomized design with a factorial 2x4 scheme (factor 1, seeds with and without previous scarification by sandpaper in the opposite side of the micropyle x factor 2, four different water temperatures for immersion during 24h).
The entire process, from the deposition of pollen on the micropyle, followed by pollen tube growth and fertilization of the egg, takes considerably longer in cycads and other gymnosperms than in angiosperms.
The eggs were also photomicrographed in both dorsal and ventral positions in order to observe both the exochorion and micropyle.
Seed dormancy was broken by a cut on the side of the upper third, region opposite to the micropyle (Brasil, 2013), and then the seeds were stored in controlled environment (18-20 [degrees]C and 50% relative air humidity) until the beginning of the experiment.
1c) towards the micropyle, which is formed by invagination of the zona radiata in its extremity (Fig.
The oocysts had a smooth, pink wall and a flat micropyle. Immature developmental stages including small microgametocytes of varied shapes within epithelial cells of the ducts (Figure 4(c)) and round macrogametocytes filled with uniform bluish-pink cytoplasmic granules (Figure 4(b)) were present in impression smears from 2B, 3C, and 6F treatment groups.
Morphologically, the oocysts are spherical to ovoid and do not present a micropyle. They also contain a single spherical to subspherical sporocyst, without a Stieda body.
AF = atretic follicle; CA = cortical alveolus; F = follicle cells; FG = fullgrown oocytes; Mi = micropyle; MO = maturing oocyte; N= nucleus/germinal vesicle; NC = nest of oogonia; Nu = nucleolus; OG = oogonium; OL = ovarian lumen; OW = ovarian wall; PG = primary growth oocytes; POC = postovulatory follicle complex; SG = secondary growth oocytes ; Y = yolk globules; ZP = zona pellucida.
This was easily performed, as the posterior end displays a micropyle. Each of the pod halves containing eggs was placed horizontally and buried in sand in a dish (9 x 2 cm).
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).