- spontaneous twinning
- embryonic duplication without external intervention, as occurs in nature.
Medical dictionary. 2011.
Medical dictionary. 2011.
Twin — Monozygotic ( identical ) twins A twin is one of two offspring produced in the same pregnancy.[1] Twins can either be monozygotic (in common parlance, identical ), meaning that they develop from one zygote that splits and forms two embryos, or… … Wikipedia
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human embryology — ▪ biology Introduction the process encompassing the period from the formation of an embryo, through the development of a fetus, to birth. The human body, like that of most animals, develops from a single cell produced by the union of… … Universalium
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calcite — calcitic /kal sit ik/, adj. /kal suyt/, n. one of the commonest minerals, calcium carbonate, CaCO3, found in a great variety of crystalline forms: a major constituent of limestone, marble, and chalk; calc spar. [1840 50; CALC + ITE1] * * * Most… … Universalium
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