Heredity and sex . male transmits his characters equally ^ith the female,it follows that the nucleus is the source of thisinheritance. The argmnent has not been regarded as entirelyconclusive, because the sperm may also bring m someof the protoplasm of the original cell—at least that parthing immediateh around the nucleus. In addition asmall body hing at the base of the sperm head seemsalso to be brought in by the male, and according tosome observers it becomes the center about which theentue di\ system or karyokinetic spindle develops. The most con^dncing evidence that the chiomosomesar
Heredity and sex . male transmits his characters equally ^ith the female,it follows that the nucleus is the source of thisinheritance. The argmnent has not been regarded as entirelyconclusive, because the sperm may also bring m someof the protoplasm of the original cell—at least that parthing immediateh around the nucleus. In addition asmall body hing at the base of the sperm head seemsalso to be brought in by the male, and according tosome observers it becomes the center about which theentue di\ system or karyokinetic spindle develops. The most con^dncing evidence that the chiomosomesare the most important elements in heredit3^ is found insome experimental work, especially that of Boveri,Baltzer, and Herbst. Under certain chcumstances in 56 HEREDITY AND SEX the sea-urchin two spermatozoa may enter a singleegg. They both unite with the egg nucleus (Fig. 31).Each brings in 18 chromosomes. The egg contributes18 chromosomes. There are in all 54, instead of 36chromosomes, as in normal
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Keywords: ., boo, bookcentury1900, bookdecade1910, booksubjectsex, bookyear1913
