Word: spermatozoon
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...follicles. FSH starts a few of these on a growth process that results in the production of one ovum (egg). Around the 14th day of the cycle, ovulation occurs: the follicle releases the ovum, which travels down the Fallopian tube toward the uterus. If it encounters a live spermatozoon on the way, or soon after its arrival, the ovum will be fertilized...
Every human being is constantly subjected to bombardment by gamma rays (X rays) from natural sources such as cosmic rays. These do no visible damage, for the body is accustomed to the low normal "level of radiation." But when a gamma ray hits the nucleus of a spermatozoon or ovum (the reproductive cells which unite to form a new individual), it may damage one of the thousands of "genes" which carry hereditary characteristics from one generation to the next. This may produce a "mutation." The child may differ slightly or radically from its parents, or the difference may lie concealed...
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...