单词 | polyspermy |
释义 | polyspermyn. Biology. Penetration of an ovum by more than one sperm. ΘΚΠ the world > life > biology > biological processes > procreation or reproduction > fecundation or impregnation > [noun] > by more than one spermatozoon polyspermy1887 1887 Amer. Naturalist 21 221 Polyspermy is where more than one male cell fuses with a female cell. 1889 P. Geddes & J. A. Thomson Evol. Sex 34 It has, however, been shown..that ‘polyspermy’, or the entrance of more than one sperm, is extremely rare. 1904 Brit. Med. Jrnl. 17 Dec. 1643 The phenomenon of polyspermy or the fertilization of the ovum by more than one spermatozoon, the cause, according to modern ideas, of double monsters. 1941 Proc. National Acad. Sci. U.S.A. 27 509 While polyspermy is a natural phenomenon in Triturus viridescens, all sperm nuclei remain separated from one another. 1973 Nature 26 Jan. 237/1 Polyspermy is a normal feature of fertilization in some organisms, such as birds and reptiles. 1992 New Scientist 4 July 38/2 One idea..is that hostility helps to reduce sperm numbers and hence avoid polyspermy (the penetration of eggs by more than one sperm) which invariably results in embryo death. This entry has been updated (OED Third Edition, September 2006; most recently modified version published online March 2022). < n.1887 |
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