Advertisement
Advertisement
megaspore
[ meg-uh-spawr, -spohr ]
noun
- the larger of the two kinds of spores characteristically produced by seed plants and a few fern allies, developing into a female gametophyte. Compare microspore.
- the embryo sac of a flowering plant.
megaspore
/ ˈmɛɡəˌspɔː /
noun
- Also calledmacrospore the larger of the two types of spore produced by some spore-bearing plants, which develops into the female gametophyte Compare microspore
- the cell in flowering plants that gives rise to the embryo sac
megaspore
/ mĕg′ə-spôr /
- One of the two types of haploid spores produced by a heterosporous plant. Megaspores develop into female gametophytes and are usually larger than microspores.
Derived Forms
- ˌmegaˈsporic, adjective
Other Words From
- meg·a·spor·ic [meg-, uh, -, spawr, -ik, -, spor, -], adjective
Word History and Origins
Origin of megaspore1
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.
The tissue at the apex of the megaspore grows slightly above the level of the archegonia, so that the latter come to lie in a shallow depression.
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.
In both forms cysts containing megaspores and megasporozoites, and others containing microspores and microsporozoites are found, considered as representing sexual differentiation thrown back to the very earliest stages of the life-cycle.
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.
Advertisement
Advertisement
Advertisement
Advertisement
Browse