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The parthenogenetic ovum of the bee is male, and yet it is an ovum capable only of producing spermatozoa. If the single X chromosomes is the cause of the development of spermatozoa in the male bee, why does it not produce spermatozoa in the gametes of the female bee, since when reduction takes place all these gametes have a single X chromosome?
By the action of air on the blood it is fitted for the purposes of life, and from the moment that animation is marked by sensation or volition, this function is performed, the punctum saliens in the ovum seems to receive as it were the breath of life in the influence of air.
Whenever we see any creature able to go through any complicated and difficult process with little or no effort whether it be a bird building her nest, or a hen's egg making itself into a chicken, or an ovum turning itself into a baby we may conclude that the creature has done the same thing on a very great number of past occasions.
The cell then looks just like an ordinary animal ovum. When it has been in this condition for some time the cell divides into two, four, eight, sixteen, thirty-two, and sixty-four cells. These arrange themselves in a round vesicle, thrust out vibratory lashes, burst the capsule, and swim about in the same magosphaera-form with which we started.
If it did so the delicate ovum would certainly be destroyed, crushed in the attempt to thrust it down a narrow passage half choked with debris. This is very perplexing. My embarrassment will be shared by all readers who are acquainted with the structure of the elephant-beetle.
This allows the blood, which is being sent to the womb to provide nourishment for the ovum if it be impregnated, to pass into the cavity of the womb, then out through the mouth into the vagina, thence to the external parts. This flow is called the menstrual flow. When the flow ceases the mucosa or lining assumes its former state. This process is repeated every month. Bladder 2. Urethra 3.
The soma with its male and female somatic characters has nothing to do with the question, since somatic sex-differences may be altogether wanting, and moreover, the essential male character, the formation of spermatozoa, is by the Mendelian hypothesis due to descent of the male gametes from the original fertilised or unfertilised ovum.
They are the central fact in our existence, the point towards which all effort is directed." Nothing could be said more truly of Woman, and the ova she carries. All that transpires during pubescence is symptomatic of the underlying tidal stir in the cells. The uterus becomes gorged with blood periodically, to provide an enriched soil for the perhaps to be fertilized ovum to plant itself.
Yet the quantity of yolk is exceedingly small. In this particular the human ovum differs notably from the egg of birds, as it does also in that it lacks a shell. Obviously, a shell would not only be useless to an embryo developing within the body of its parent, but would shut off the nourishment, which, since the ovum contains so little, must necessarily be provided by the mother.
The human male cell must travel some distance to reach the point where it can meet a ripe and vigorous ovum; and since the journey is not without danger to its life, Nature has provided that exceedingly large numbers of the male cells shall be deposited in the vagina at the time of the marital relation.
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