inner cell mass

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Related to inner cell mass: blastocyst, trophoblast, blastocyst cavity, embryoblast


1. a lump or collection of cohering particles.
2. that characteristic of matter that gives it inertia. Symbol m.
atomic mass atomic weight; see also atomic mass unit.
inner cell mass an internal cluster of cells at the embryonic pole of the blastocyst which develops into the body of the embryo.
lean body mass that part of the body including all its components except neutral storage lipid; in essence, the fat-free mass of the body.
relative molecular mass technically preferable term for molecular weight.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


The mass of cells at the embryonic pole of the blastocyst that forms the embryo and some extraembryonic or adnexal tissues.
Synonym(s): inner cell mass
[embryo- + G. blastos, germ]
Farlex Partner Medical Dictionary © Farlex 2012


The cells at the embryonic pole of the blastocyst concerned with formation of the embryo per se.
Synonym(s): inner cell mass.
[embryo- + G. blastos, germ]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
References in periodicals archive ?
Energy metabolism of the inner cell mass and trophectoderm of the mouse blastocyst.
Bongso, "Human feeders support prolonged undifferentiated growth of human inner cell masses and embryonic stem cells," Nature Biotechnology, vol.
The procedure of Thouas et al11 was carried out for the differential staining of inner cell mass and trophectoderm cells.
The IMO groups' blastocysts had brighter appearance, more prominent inner cell mass and less irregularities compared with blastocysts produced in SOFaaBSA alone (Figure 1).
Cell allocation of ovine blastocysts derived from oocytes matured in different maturation media IVM media Blastocysts * Total cell ICM (1) n M[+ or -]SEM M[+ or -]SEM TCM-FCS 19 54.6[+ or -]4.6 12.6[+ or -]1.0 TCM-BSA 14 53.1[+ or -]4.5 12.7[+ or -]1.1 SOF-FCS 20 57.8[+ or -]3.9 12.5[+ or -]0.9 SOF-BSA 13 57.1[+ or -]4.5 13.1[+ or -]1.0 IVM media TE (2) ICM/TE M[+ or -]SEM %[+ or -]SEM TCM-FCS 41.9[+ or -]3.7 23.6[+ or -]0.7 TCM-BSA 40.4[+ or -]3.4 23.8[+ or -]0.9 SOF-FCS 45.3[+ or -]3.2 22.0[+ or -]1.1 SOF-BSA 44.0[+ or -]3.8 23.2[+ or -]1.2 * 6-day old blastocysts (1): Inner cell mass; (2): Trophectoderm cells Table 3.
The inner cell mass has undergone another fate decision and has differentiated into three layers: endoderm, mesoderm, and ectoderm.
Embryonic Stem cells (ES) cells from the inner cell mass of normal human blastocysts were cultured and maintained normally for many passages in 1998.
These cells are derived from the inner cell mass of 3.5-day-old blastocysts [1,2].
When removed from the blastocyst and cultured in a glass dish in the laboratory, the inner cell mass gives rise to ESCs.
Once a fertilized egg has gone through several rounds of division, stem cells form a bulge, called the inner cell mass, inside the early embryo.
After about five days, a blastocyst forms: Cells move to form a thin layer around the edge and a group of small cells, called the inner cell mass, assembles along one side.
Blastocyst--A sphere made up of an outer layer of cells (the trophectoderm), a fluid-filled cavity (the blastocoel), and a cluster of cells on the interior (the inner cell mass).