- cleavage pole
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полюс спайности
English-Russian dictionary of geology. 2011.
English-Russian dictionary of geology. 2011.
Cleavage (embryo) — In embryology, cleavage is the division of cells in the early embryo. The zygotes of many species undergo rapid cell cycles with no significant growth, producing a cluster of cells the same size as the original zygote. The different cells derived … Wikipedia
cleavage — 1. Series of mitotic cell divisions occurring in the ovum immediately following its fertilization. SYN: segmentation (2). SEE ALSO: c. division. 2. Splitting of a complex molecule into two or more simpler molecules. SYN: scission (2). 3 … Medical dictionary
pole cell — noun Etymology: pole (IV) + cell : a cleavage cell of the embryo of various insects and some other invertebrates regularly undergoing early chromatin diminution in somatic cells that retains the full chromatin complement and ultimately gives rise … Useful english dictionary
discoidal cleavage — n meroblastic cleavage in which a disk of cells is produced at the animal pole of the zygote (as in bird eggs) * * * cleavage limited to the animal pole of highly telolecithal zygotes … Medical dictionary
radial cleavage — noun Date: 1973 holoblastic cleavage that is typical of deuterostomes and that is characterized by arrangement of the blastomeres of each upper tier directly over those of the next lower tier resulting in radial symmetry around the pole to pole… … New Collegiate Dictionary
spiral cleavage — noun Date: 1892 holoblastic cleavage that is typical of protostomes and that is characterized by arrangement of the blastomeres of each upper tier over the cell junctions of the next lower tier so that the blastomeres spiral around the pole to… … New Collegiate Dictionary
spiral cleavage — Pattern of early cleavage found in molluscs and annelids (both mosaic eggs). The animal pole blastomeres are rotated with respect to those of the vegetal pole. The handedness of the spiral twist shows maternal inheritance … Dictionary of molecular biology
discoidal cleavage — noun : meroblastic cleavage in which a disk of cells is produced at the animal pole of the zygote (as in bird eggs) compare superficial cleavage … Useful english dictionary
discoidal cleavage — noun Date: circa 1909 meroblastic cleavage in which a disk of cells is produced at the animal pole of the zygote (as in bird eggs) … New Collegiate Dictionary
unequal cleavage — division of the zygote in which the blastomeres about the vegetal pole remain larger than those nearer the animal pole … Medical dictionary
animal development — Introduction the processes that lead eventually to the formation of a new animal starting from cells derived from one or more parent individuals. Development thus occurs following the process by which a new generation of organisms is produced by … Universalium