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单词 nucellus
释义

nucellusn.

Brit. /njuːˈsɛləs/, U.S. /n(j)uˈsɛləs/
Origin: A borrowing from French. Etymon: French nucelle.
Etymology: < French nucelle (C. F. B. de Mirbel 1830, in Mém. de l'Acad. Royale des Sciences 9 610) < classical Latin nuc- , nux nut (see nut n.1) + French -elle , diminutive suffix (see -ella suffix); compare -ellus suffix. Compare earlier nucleus n. 4c.French nucelle occurs in English context in 1832:1832 J. Lindley Introd. Bot. ii. 155 The central part is a fleshy, pointed, pulpy mass, called the nucleus or nucelle. The French word is borrowed as nucella (in English or scientific Latin) in the 1850s:1856 Dict. Bot. Terms Nucella, synonyme for nucleus.1857 R. G. Mayne Expos. Lexicon Med. Sci. (1860) Nucella, applied by Mirbel to a pulpy body entirely composed of loose cellular tissue without any appearance of membrane, found in the centre of the ovule when it begins to develope itself and which does not adhere to the two envelopes, the primine and secundine but to the base of the ovule.
Botany.
The undifferentiated tissue of the ovule, in which the embryo sac develops.Cf. earlier nucleus n. 4c.
ΘΚΠ
the world > plants > part of plant > reproductive part(s) > flower or part containing reproductive organs > [noun] > parts of > ovule
ovum1703
ovulum1786
ovule1800
nucellus1882
1882 S. H. Vines tr. J. von Sachs Text-bk. Bot. (ed. 2) ii. iv. 487 That part of the ovule in which the embryo-sac arises (the nucellus [Ger. Knospenkern; 1875 Eng. ed. nucleus]) must be considered the equivalent of the macrosporangium.
1887 R. Bentley Man. Bot. (ed. 5) i. iv. 329 Some ovules, as those of the Mistletoe.., consist simply of the nucellus..and embryo-sac,..in which case the nucellus is termed naked.
a1933 J. A. Thomson Biol. for Everyman (1934) II. 1152 The nucellus of the ovule is the large megasporangium, and in it one megaspore, called the embryo-sac, comes to maturity.
1959 Jrnl. Ecol. 47 197 Six ovules develop, but in those which are aborting the nucellus begins to degenerate before it is ready for fertilization.
1998 New Scientist 18 July 17/1 Pollen of the right species grows through the nucellus, but alien pollen is usually rebuffed.
This entry has been updated (OED Third Edition, December 2003; most recently modified version published online June 2022).
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n.1882
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