Jstor the egg and the sperm

In the Johns Hopkins lab's revised model, the egg ends up as the female aggressor who "captures and tethers" the sperm with her sticky zona, rather like a spider lying in wait in her web. For example, rather than improving the chance that a spermatozoon will meet an egg cell, nature finds it easier to produce millions of spermatozoa. January 1, December 26, The myth about sperm and eggs Aeon by Robert D. The proper female analogy to spermato- genesis, biologically, is ovulation. Such tropistic phenomena may be exhibited in response to CO2 and other acids Nereis , or certain constituents of egg secretions, to mention only chemotaxis. He is reluctant to launch himself into the darkness, afraidof contraceptive devices, afraid of winding up on the ceiling if the man masturbates.
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Martin / EGG AND THE SPERM

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Pronucleus

I cannot accept this statement of the problem, I have nevertheless taken into consideration the fundamental fact, to which Loeb alludes, in the full account of my experiments, which appeared after Loeb's paper was in press. When he refers to processes going on within eggs, he stops there. The egg could still be regarded as a self-contained system with no more than the usual environmental relations. As he described it, "the interaction between what is already known, what remains to be learned, and those who are to apprehend it, go to ensure harmony within the system. Northwestern University Press, , Emily Martin Reviewed work s:
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Full text of "Sperm Agglutination and Fertilization"

Rosalind Petchesky points out that through visual representations such as sonograms, we are given "images of younger and younger, and tinier and tinier, fetuses being 'saved. A study of this problem by one of my students will appear soon. Another objection in which Loeb supports the possibility of superposing fertilization on parthenogenesis will be dealt with in a separate paper. There are secretions which mitigate the urine in the urethra before ejaculation, to protect the sperm. In this recent investigation, the researchers began to ask ques- tions about the mechanical force of the sperm's tail. In the past, cybernetic models have played an important part in the imposition of social control.
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Yet the sperm, just as much as the egg, is dependent on a great many related processes. Later research showed that the sperm released digestive enzymes that chemically broke down the zona; thus, scientists presumed that the sperm used mechanical and chemical means to get through to the egg. The fundamental fact is simply that the fertilization process in some cases can be divided in two sharply marked stages. Lange Medical Publications, , Books by Language uslprototype. I cannot accept this statement of the problem, I have nevertheless taken into consideration the fundamental fact, to which Loeb alludes, in the full account of my experiments, which appeared after Loeb's paper was in press.
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