megaspore

American  

[meg-uh-spawr, -spohr] / ˈmɛg əˌspɔr, -ˌspoʊr /

noun

Botany.

1. the larger of the two kinds of spores characteristically produced by seed plants and a few fern allies, developing into a female gametophyte.

2. the embryo sac of a flowering plant.

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megaspore British  

/ ˈmɛɡəˌspɔː /

noun

1. Also called: macrospore.  the larger of the two types of spore produced by some spore-bearing plants, which develops into the female gametophyte Compare microspore

2. the cell in flowering plants that gives rise to the embryo sac

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megaspore Scientific  

/ mĕg′ə-spôr /

1. One of the two types of haploid spores produced by a heterosporous plant. Megaspores develop into female gametophytes and are usually larger than microspores.

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Other Word Forms

• megasporic adjective

Etymology

Origin of megaspore

First recorded in 1885–90; mega- + spore

Example Sentences

Other fossilized finds include a pinecone-like structure with megaspores and some fossilized tree trunks used to estimate the height of the trees, Wang noted.

From Fox News

Each megaspore may contain 2 to 6 archegonia.

From Project Gutenberg

For an account of the further development of the megaspore, and the formation of the egg-cell, from which after fertilization is formed the embryo, see Gymnosperms and Angiosperms.

From Project Gutenberg

The behaviour of the chromosomes in meiosis or reduction division both in the pollen mother-cells and in the megaspore mother-cells which give rise to the so-called embryo-sac are fully described by Gates.

From Project Gutenberg

The megaspore 763 is filled with tissue as in typical Gymnosperms, and from some of the superficial cells 3 to 5 archegonia are developed, characterized by long multicellular necks.

From Project Gutenberg