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One of the small blastomeres found in a developing embryo.

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Biology) embryol any of the small cells formed by unequal cleavage of a fertilized ovum
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈmaɪ krəˌmɪər)

one of the small blastomeres that form toward the animal pole in embryos that undergo unequal cleavage.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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[24.] Juliano CE, Voronina E, Stack C, Aldrich M, Cameron AR (2006) Germ line determinants are not localized early in sea urchin development, but do accumulate in the small micromere lineage.
Spatial aspects of cell interactions involved in the determination of dorsoventral polarity in equally cleaving gastropods and regulative abilities of their embryos, as studied by micromere deletions in Lymnaea and Patella.
"Micromere" formation and expression of endomesoderm regulatory genes during embryogenesis of the primitive echinoid Prionocidaris baculosa.
A regulatory gene network that directs micromere specification in the sea urchin embryo.
A Ral/MEK/ERK signaling pathway is required for development of the sea urchin embryo micromere lineage through phosphorylation of the transcription factor Ets.
Micromere descendants at the blastula stage are involved in normal archenteron formation in sea urchin embryos.
Lambert and Nagy (2001) demonstrated that activated ERK1/2, MAPK is required in the D quadrant (i.e., 3D) and subsequently in specific micromere progeny of the A and C quadrants for proper cell specification and dorsoventral (DV) axis formation in the gastropod Ilyanassa.
obsoleta Hb-like proteins are expressed in every micromere and macromere nucleus from one cell to at least the sixth cleavage division.
Molluscs, like most other lophotrochozoans, exhibit a highly conserved pattern of spiral cleavage that generates four macromeres surmounted by four tiers of micromere quartets.
It remained attached to the vegetal pole of the embryo as a spherical packet of red-colored cytoplasm ("red body") at least through the period when micromere quartets were generated (Fig.
Micromere differentiation in the sea urchin embryo: expression of primary mesenchyme cell specific antigen during development.
Development of a "'primitive" sea urchin (Eucidaris tribuloides): irregularities in the hyaline layer, micromeres, and primary mesenchyme.