Word: chromatin
(lookup in dictionary)
(lookup stats)
Dates: during 1960-1969
Sort By: most recent first
(reverse)
...grown into tiny embryos but had not yet become implanted in the uterine wall. They placed each embryo under a microscope, cut a tiny slit in its surrounding membrane and drew out several hundred cells with a suction pipette. The cells were then examined for the presence of sex chromatin, a substance found only in female cells. Separated into male and female groups, the embryos were next placed in a culture medium, a laboratory equivalent of a hospital recovery room...
From that same sample, the Albany researchers have also learned to determine an unborn infant's sex. Micro scopic examination of carefully cultivated slides, they discovered, reveals the presence or absense of the sex-chromatin body that determines femininity. And in every case in which the sample was adequate, not only did all the researchers agree on their prediction, but in every case they were correct. Enthusiastically they reported that there is no reason why the test should not always be 100% accurate. Then they quickly added a word of caution. Since obtaining a sample of the amniotic fluid...
...little dark spot that others lack. Yet not until 1949 did Canadian Neuro-Anatomist Murray L. Barr realize that the spots, which he was studying in cats' nerve cells, appear only in cells from females. Later research showed that the spots, now known as "Barr bodies" or sex chromatin, consisted of one X chromosome - the one that is inactivated after it has done its job of helping to determine femaleness...