| 释义 |
micropyle|ˈmaɪkrəʊpaɪl|
[a. F. micropyle, f. Gr. µῑκρό-ς small + πύλη gate.]
1. Bot. The foramen or orifice in the integument of an ovule, by which the pollen penetrates to the apex of the nucleus or radicle. Also, the external aperture which represents this foramen in the mature seed.
1821tr. Decandolle & Sprengel's Elem. Philos. Plants 79 In the seeds of many of the Leguminous plants, a small cavity appears under the umbilicus, called micropyle, but its use is unknown. 1830Lindley Nat. Syst. Bot. 181 The woody shell of the seed of Sapoteae is certainly testa,..as is proved by the presence of the micropyle upon it. 1875Bennett & Dyer tr. Sachs' Bot. 429 It [the pollen] then forces itself into the micropyle and advances as far as the embryo-sac.
2. Zool. A special opening in a female cell for the entrance of the fertilizing cell.
1859Todd's Cycl. Anat. V. [97]/2 Discoveries..as to the existence of the micropyle in fishes. 1875Ray Lankester in Q. Jrnl. Microsc. Sci. XV. 38 The egg-shell..has a small hole at the narrower pole, which may be called a micropyle. 1893Tuckey Amphioxus 41 This..explains how it is that without the formation of a micropyle the spermatozoon can force its way into the egg. |