Word: spermatozoon
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Dates: during 1930-1939
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Normally the male spermatozoon is what determines the sex of the offspring. If the spermatozoon has a male-determining chromosome pattern in its nucleus, the sex will be male; if not, female. Since there was no spermatozoon in the case of the fatherless rabbit, therefore no male-determining pattern, the Pincus rabbit is a female. She seems to be perfectly normal. Mated to an ordinary buck, she produced a normal litter. These bunnies are the first in rabbit history with no maternal grandfather...
...continued far enough, it will be possible to explain in exact mathematical terms-in terms of atomic energy levels and electronspins-what happens when insulin is secreted in the pancreas, when starch is broken down in the digestive system, when an ovum is penetrated and fertilized by a spermatozoon, many & many a complex biological phenomenon...
...great discoveries of modern genetics is that certain hereditary characters are linked to the sex factor. Males manufacture two kinds of spermatozoa, one bearing a y-chromosome, the other an x-chromosome. If a y-chromosome spermatozoon happens to penetrate the female ovum, the get is a boy; if an x-chromosome, it is a girl. Thus Professor Crew reasoned the shorter life expectancy of the male seems to be carried on a gene or genes in the y-chromosome. By delicate manipulations, geneticists have had some success in separating male and female elements in mammalian sperm, opening the prospect...