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Related to Morula: blastocoel, trophoblast, embryoblast


A solid mass of blastomeres formed by cleavage of the eggs of many animals; precedes the blastula or gastrula, depending on the type of egg.
(invertebrate zoology)
A cluster of immature male gametes in which differentiation occurs outside the gonad; common in certain annelids.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



a stage in the development of the embryo in multicellular animals, preceding the completion of the period of cleavage. In the morula stage, the embryo is a mass of cells (blastomeres) that resembles the aggregate fruit (“berry”) of the raspberry, blackberry, or mulberry. The morula stage is followed by the blastula stage.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
(76.) Morula stage is the point at which the zygote has divided several times into a cluster of cells.
Clinical pregnancy rates were 63% for two blastocysts, 32% for one blastocyst and one morula, and 17% for two morulae.
Over the next few years, VPR&D plans to cultivate morula and other wild fruit products and market them abroad.
Percentages of zygotes developed to morula and blastocyst stages were evaluated on days 5 and 8, respectively.
Cultura, democracia e socialismo: as ideias de Carlos Nelson Coutinho em debate.--1.ed.--Rio de Janeiro: Morula, 2016.
Reactive oxygen species are also produced when cytotoxic morula cells sense the presence of nonself (Ballarin et al., 2001) and release the enzyme phenoloxidase, which is stored in an inactive form inside their granules (Cima et al., 2004; Franchi et al., 2015).
The first attempt of identifying the embryonic development of Omani abalone was conducted by Stirn and Al Hashmi (1996) which identified six stages; nonfertilized egg, cleavage (4-cell stage), advanced embryo (morula), unhatched trochophore larvae, initial veliger, and finally advanced veliger.
Los estados de desarrollo embrionario descritos son: eliminacion del primer corpusculo polar, embrion de dos celulas, tetrada, morula, trocofora intracapsular y veligera intracapsular; eclosionando una larva en estado de veligera planctotrofica ~20 dias post-postura (Contreras & Perez, 2010).
The research on mechanisms directing blastocyst formation has demonstrated that (a) [Na.sup.+]/[K.sup.+]/ATPase has a polarized distribution confined to the trophectoderm basolateral membrane regions just before the onset of cavitation, (b) expression of [Na.sup.+]/[K.sup.+]/ATPase subunit genes are up-regulated during the morula to blastocyst transition, (c) treatment with ouabain (a potent and specific inhibitor of the [Na.sup.+]/[K.sup.+]/ATPase) affects cavitation and blastocyst formation in a number of mammalian species, and (d) [Na.sup.+]/[K.sup.+]/ATPase regulates the formation and function of trophectoderm tight junctions (6).
The maturation rate and development to morula and blastocyst stage for oocytes matured at 10 ug ml-1 fenugreek seed extract was significantly higher than those matured at 1ug ml-1 of fenugreek seed extract and the control group.