In the previous sections of this Chapter examined organ systems that support the processes of metabolism. Here we will tell you about the reproductive system, the most important biological function of which is the preservation and continuation of the human race.
Man, like all mammals, is being bisexual. In the course of evolution, plant and animal sexual reproduction has established itself as the most common form of procreation. As pointed out by A. Barnett, "the explanation of this phenomenon should probably look for is that all kinds of living things evolve, and the advantage of sexual reproduction is to obtain one individual traits of both parents to two different individuals. It enables a more diverse to adapt and survive, especially in the changing conditions, and for the species is the potential relatively rapid evolution" *.
It is thus clear that gender differences in humans has deep biological roots and this is the reason for the similarities in the structure of the reproductive systems of humans and animals. But here the similarity ends: it will be shown that in the process of formation of modern man in the functions of the reproductive system appear most essential features inherent to man. These features are due to the second signal system, conscious human activity, conditions and level of development of its social life.
Will meet first with the structure of the reproductive system.
Although, at first glance, it seems that the structure of the male and female reproductive system completely different (compare schematic Fig. 21, 23), in reality the structure can be noted. In both cases, there are two groups of institutions : external and internal genital organs, and the complex of internal genital organs, the main role belongs to a sex gland. All other education related to complex internal organs, are putting way to germ cells, and the extension of cancer. General plan of the structure of the male and female reproductive system is explained by the fact that the formation of the embryo both male and female reproductive system develops from a single pair of embryo, which is located on both sides of the spine almost the entire length. Only in the third month of fetal life of the fetus occurs differentiation of embryonic stage of the reproductive system and the fetus shows signs floor **. The development of the organs of the female and male reproductive system of the common germ helps to explain some of the vices (deviations from the norm) of their structure, they have to meet in life.
* A. Barnett. The human race. M., 1968, page 67,
** Currently, special investigations microscopy (fluorescent method) according to the structure of chromosomes can determine the sex of a fetus before birth the fetus. The gender differences are installed on the presence of the X-chromosome (typical female cells) or Y chromosome (peculiar to men's cells), which are revealed in the study mentioned method (jury. "Science and life", 1071, 8, pp. 112-113).