sheath of Hertwig

sheath of Hertwig
sheath of Hert·wig -' n a two-layered epithelial wall that covers the developing root of a tooth, is derived from cells of the enamel organ, and later breaks up during the process of cement deposition called also Hertwig's sheath
Hert·wig 'hert-.vik Wilhelm August Oskar (1849-1922)
German embryologist and cytologist. Hertwig's important investigations concerned the nuclear transmission of hereditary characteristics, biogenetic theory, and the effect of radium rays on somatic and germ cells. He is most famous for being the first to recognize that the fusion of the nuclei of the sperm and ovum is the central event in fertilization. He also made the important observation that only one spermatozoan is required to fertilize one egg. With his brother, Richard von Hertwig, he studied the formation of the coelom and the theory of the germ layer.

Medical dictionary. 2011.

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