单词 | ovule |
释义 | ovule[ ov-yool, oh-vyool ] / ˈɒv yul, ˈoʊ vyul / SEE SYNONYMS FOR ovule ON THESAURUS.COM nounBotany.
Biology. a small egg. Origin of ovuleFirst recorded in 1820–30, ovule is from the Latin word ōvulum little egg. See ovum, -ule Words nearby ovuleovular membrane, ovulate, ovulation, ovulation method, ovulatory, ovule, ovulocyclic, ovulum, ovum, ow, Owatonna Dictionary.com UnabridgedBased on the Random House Unabridged Dictionary, © Random House, Inc. 2020 Example sentences from the Web for ovuleBritish Dictionary definitions for ovuleovule / (ˈɒvjuːl) / nouna small body in seed-bearing plants that consists of the integument(s), nucellus, and embryosac (containing the egg cell) and develops into the seed after fertilization zoology an immature ovum Derived forms of ovuleovular, adjectiveWord Origin for ovuleC19: via French from Medieval Latin ōvulum a little egg, from Latin ōvum egg Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012 Medical definitions for ovuleovule [ ō′vyōōl, ŏv′yōōl ] n.A small or immature ovum of a mammal. A small egglike structure.ovulum Other words from ovuleo′vu•lar (ō′vyə-lər, ŏv′yə-) null adj.The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company. Scientific definitions for ovuleovule [ ō′vyōōl, ŏv′yōōl ] The female reproductive structure that develops into a seed in a seed-bearing plant. An ovule consists of a megasporangium surrounded by one or two layers of tissue called integuments. The megasporangium produces spores that develop into megagametophytes. These megagametophytes remain within the tissues of the ovule and produce one or more egg cells. Sperm from pollen grains enter the ovule through an opening called a micropyle and fertilize the egg cells. The resulting embryo then begins to develop within the ovule, which becomes a seed. Among the conifers and cycads, the ovules are typically found in pairs on scales in the female cones. The ovules of angiosperms are contained in a structure called the ovary within in the flower. See more at flower gametophyte megasporogenesis pollination. The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved. |
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