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Updated: June 29, 2025
"The irresistible passion that draws Edward to the sympathetic Otillia, or Paris to Helen, and leaps all bounds of reason and morality, is the same powerful, unconscious, attractive force which impels the living spermatozoon to force an entrance into the ovum in the fertilisation of the egg of the animal or plant the same impetuous movement which unites two atoms of hydrogen to one atom of oxygen for the formation of a molecule of water."
Anything that causes this alteration without endangering the rest of the egg may induce its development." When the spermatozoon enters the ovum it causes some alteration in the surface membrane of the latter which, amongst other things, prevents the entrance of further spermatozoa. Loeb thinks that in causing this alteration it sets up the segmentation of the ovum.
We find the task of unravelling the writer's meaning rendered more difficult by a certain confusion in his use of terms, since fertilisation, i.e. syngamy the union of the different sex products seems to be confused with segmentation, i.e. germination; and this confusion is accentuated by the claim that "the main effect of the spermatozoon in inducing the development of the egg consists in an alteration in the surface of the latter which is apparently of the nature of a cytolysis of the cortical layer.
In this way, it is made sure that some of them will travel up through the uterus and oviducts, arriving in the neighborhood of the ovaries. FERTILIZATION. Convincing observations upon the lower forms of life, especially upon fishes, have shown that when the germinal cells come near to each other, the ovum attracts the spermatozoon.
It was strange how so little a thing as the union of a spermatozoon and an ovum could produce so much trouble. He looked across the office at Copper placidly filing case cards. She wasn't worrying. With sublime faith, she was sure that he would find the answer, the one that would solve everything. He shuddered. The only logical solution was abortion and that was unthinkable!
Such a result is prevented through the process to which we have referred in the preceding chapter as the ripening of the ovum, and also through a similar process in the case of the spermatozoon.
We have seen that the spermatozoon represents the solitary contribution of the father toward the development of the child, and the spermatozoon, therefore, must convey the material basis of paternal inheritance. Similarly we might expect the ovum to be the bearer of the maternal qualities inherited by the child.
On the other hand, single ovum, or identical, twins are always of the same sex; this follows, since but one egg and but one spermatozoon are here concerned. The incident permitting twins to develop from a solitary ovum must occur soon after conception has taken place. It will be remembered that the first step in the development of the fertilized ovum consists in its dividing into two cells.
He experimented with frogs, tortoises, and dogs; and settled beyond question the function of the ovum and spermatozoon. Unfortunately he misinterpreted the part played by the spermatozoa in believing that their surrounding fluid was equally active in the fertilizing process, and it was not until some forty years later that Dumas corrected this error.
In the human spermatozoon the head is ovoid, appearing pear-shaped or pointed in one view and elliptical in another. The epididymis referred to above, consists of a mass of coiled tubes and blood vessels.
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