micropyle

Definitions

  • WordNet 3.6
    • n micropyle minute opening in the wall of an ovule through which the pollen tube enters
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Webster's Revised Unabridged Dictionary
    • n Micropyle (Biol) An opening in the membranes surrounding the ovum, by which nutrition is assisted and the entrance of the spermatozoa permitted.
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Century Dictionary and Cyclopedia
    • n micropyle In botany, the orifice or canal in the coats of the ovule leading to the apex of the nucleus, through which the pollen-tube penetrates. The name is also applied to the corresponding part of the seed, which indicates the position of the embryo. See foramen, 2. See cut under amphitropous.
    • n micropyle In zoology: The scar or hilum of an ovum at the point of its attachment to the ovary
    • n micropyle Any opening in the coverings of an ovum through which spermatozoa may gain access to the interior, or a cluster of minute pores on the surface of an egg through which fertilization is effected. On the eggs of lepidopterous insects these pores often form a rosette at one end.
    • n micropyle In zoology: In certain sporozoans, a minute opening in the oöcyst through which the microgamete enters to fertilize the macrogamete.
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Chambers's Twentieth Century Dictionary
    • n Micropyle mī′krō-pīl (bot.) the orifice in the coats of the ovule leading to the apex of the nucleus, through which the pollen-tube penetrates:
    • n Micropyle mī′krō-pīl (zool.) the hilum of an ovum at the point of attachment to the ovary: any opening in the coverings of an ovum by which spermatozoa may find entrance.
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Etymology

Webster's Revised Unabridged Dictionary
Micro-, + Gr. gate, orifice: cf. F. micropyle,
Chambers's Twentieth Century Dictionary
Gr. mikros, small, pylē, a gate.

Usage

In literature:

The primary root of the embryo in all Angiosperms points towards the micropyle.
"Encyclopaedia Britannica, 11th Edition, Volume 2, Part 1, Slice 1" by Various
This opening is called the "micropyle," and allows the pollen tube to enter.
"Elements of Structural and Systematic Botany" by Douglas Houghton Campbell
Micropyles: minute openings in the egg, through which spermatozoa enter.
"Explanation of Terms Used in Entomology" by John. B. Smith
The micropyle m is very wide.
"Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 5" by Various
This arillode, after growing downwards, may be reflected upwards so as to cover the micropyle.
"Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 3" by Various
Inverted and straight, with the micropyle next the hilum and the radicle consequently inferior.
"The Manual of the Botany of the Northern United States" by Asa Gray
This hole is identical with the micropyle in the seed.
"A Civic Biology" by George William Hunter
The surface of this column is in contact with a micropyle in the egg-membrane.
"The Works of Francis Maitland Balfour, Volume 1" by Francis Maitland Balfour
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