Thesaurus: segmentation

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1. n. The act or process of dividing into segments; specifically (Biol.), a self-division into segments as a result of growth; cell cleavage; cell multiplication; endogenous cell formation.
2. n. (embryology) the repeated division of a fertilised ovum
3. n. the act of dividing or partitioning; separation by the creation of a boundary that divides or keeps apart
4. The act or process of dividing into segments; specifically (Biol.), a self-division into segments as a result of growth; cell cleavage; cell multiplication; endogenous cell formation. Segmentation cavity (Biol.), the cavity formed by the arrangement of the cells in segmentation or cleavage of the ovum; the cavity of the blastosphere. In the gastrula stage, the segmentation cavity in which the mesoblast is formed lies between the entoblast and ectoblast. See Illust. of Invagination. -- Segmentation nucleus (Biol.), the body formed by fusion of the male and female pronucleus in an impregnated ovum. See the Note under Pronucleus. -- Segmentation of the ovum, or Egg cleavage (Biol.), the process by which the embryos of all the higher plants and animals are derived from the germ cell. In the simplest case, that of small ova destitute of food yolk, the ovum or egg divides into two similar halves or segments (blastomeres), each of these again divides into two, and so on, thus giving rise to a mass of cells (mulberry mass, or morula), all equal and similar, from the growth and development of which the future animal is to be formed. This constitutes regular segmentation. Quite frequently, however, the equality and regularity of cleavage is interfered with by the presence of food yolk, from which results unequal segmentation. See Holoblastic, Meroblastic, Alecithal, Centrolecithal, Ectolecithal, and Ovum. -- Segmentation sphere (Biol.), the blastosphere, or morula. See Morula.
5. The act or process of dividing into segments; specifically(Biol.), a self-division into segments as a result of growth; cellcleavage; cell multiplication; endogenous cell formation.Segmentation cavity (Biol.), the cavity formed by the arrangement ofthe cells in segmentation or cleavage of the ovum; the cavity of theblastosphere. In the gastrula stage, the segmentation cavity in whichthe mesoblast is formed lies between the entoblast and ectoblast. SeeIllust. of Invagination.-- Segmentation nucleus (Biol.), the body formed by fusion of themale and female pronucleus in an impregnated ovum. See the Note underPronucleus.-- Segmentation of the ovum, or Egg cleavage (Biol.), the process bywhich the embryos of all the higher plants and animals are derivedfrom the germ cell. In the simplest case, that of small ova destituteof food yolk, the ovum or egg divides into two similar halves orsegments (blastomeres), each of these again divides into two, and soon, thus giving rise to a mass of cells (mulberry mass, or morula),all equal and similar, from the growth and development of which thefuture animal is to be formed. This constitutes regular segmentation.Quite frequently, however, the equality and regularity of cleavage isinterfered with by the presence of food yolk, from which resultsunequal segmentation. See Holoblastic, Meroblastic, Alecithal,Centrolecithal, Ectolecithal, and Ovum.-- Segmentation sphere (Biol.), the blastosphere, or morula. SeeMorula.
6. n:100 n (embryology) the repeated division of a fertilised ovum n the act of dividing or partitioning; separation by the creation of a boundary that divides or keeps apart