Heredity and sex . question a different re-sult follows, as shown by the diagram. From 90 to95 per cent of the offspring are regular, but 5 per centof the females and 5 per cent of the males are uncon-formable, yet persistently appear in this stock. The results can be explained if we suppose that thetwo sex chromosomes in the egg sometimes stick to-gether (Fig. 107). They will then either pass out intoone of the polar bodies, in which case the red-eyed maleswill develop if the egg is fertilized by a female-producingsperm; or the two sex chromosomes will both stay inthe egg, and give a kind of
Heredity and sex . question a different re-sult follows, as shown by the diagram. From 90 to95 per cent of the offspring are regular, but 5 per centof the females and 5 per cent of the males are uncon-formable, yet persistently appear in this stock. The results can be explained if we suppose that thetwo sex chromosomes in the egg sometimes stick to-gether (Fig. 107). They will then either pass out intoone of the polar bodies, in which case the red-eyed maleswill develop if the egg is fertilized by a female-producingsperm; or the two sex chromosomes will both stay inthe egg, and give a kind of female with three sex chro-mosomes. Here also numerous tests can be made. They verify 224 HEREDITY AND SEX the expectation. Thus by utihzing sex chromosomesthat carry other sex-hnked characters than white eyes,it can be shown that the results are really due to thewhole sex chromosome being involved, and not toparts of it. The result is of unusual interest in anotherdirection; for it shows that the female-producing. V/ V
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Keywords: ., boo, bookcentury1900, bookdecade1910, booksubjectsex, bookyear1913
