Minggu, 20 Desember 2009



Male reproductive system includes the reproductive organs, spermatogenesis and hormones in men.
Reproductive organs
Reproductive organs of male reproductive organs and reproductive organs in luar.Spermatogenesis
Spermatogenesis occurred in the in the testes, specifically in the seminiferous tubules. Spermatogenesis involves maturation germinal epithelium cells through the process of cell division and differentiation, which aims to membentu functional sperm. Cell maturation occurs in the seminiferous tubules are then stored in the epididymis.
Seminiferous tubule walls are composed of connective tissue and epithelial tissue germ (seed epithelial tissue) are functioning at the time of spermatogenesis. Shuttle-shuttle found in the seminiferous tubules in testes spaces (lobular testis). One testicle usually contains about 250 lobules of the testes. Seminiferous tubules consist of a large amount of germinal epithelial cells (epithelial cells of seeds) called spermatogonia (spermatogonia = single). Spermatogonia are located in two or three outer layers of epithelial cells of the seminiferous tubules. Spermatogonia divide continued to reproduce themselves, some of the undifferentiated spermatogonia through the stages of development to form a sperm specific.
In the first stage of spermatogenesis, the spermatogonia are diploid (2n or 23 chromosomes containing pairs), gathered at the edge of the membrane called the germinal epithelium of spermatogonia type A. Spermatogenia type A in mitosis split into type B spermatogonia Then, after a couple of times splitting, these cells eventually become primary spermatocytes which are still diploid. After passing a few weeks, each primary spermatocyte divides by meiosis to form two secondary spermatocytes are haploid. Secondary spermatocytes then divide again by meiosis to form four spermatids. Spermatids are candidates who have not sperm tail and are haploid (n or 23 chromosomes that contain unpaired). Each will spermatids differentiate into spermatozoa (sperm). The process of change spermatids into sperm called spermiasi.
When first formed spermatids, spermatids has a shape such as epithelial cells. However, after the spermatids began lengthwise into sperm, it would appear form consisting of heads and tails.
Sperm head consists of a thick core of cells with little cytoplasm. At the membrane surface at the end of the sperm head is a thick veil called akrosom. Akrosom contains hyaluronidase and proteinase enzymes whose function is to penetrate the protective layer of the ovum.
In the sperm tail loss sperm is located in the middle sperm. Body sperm contains mitochondria that functions as a producer of energy for sperm motility.
All stages of spermatogenesis is due to the influence of Sertoli cells that have specific functions to provide food and manage the process of spermatogenesis.


Include the female reproductive system organs of reproduction, oogenesis, hormones in women, fertilization, pregnancy, childbirth and laktasi.Oogenesis
Oogenesis is the process of formation of ova in the ovary. In the ovaries contain oogonia (oogonia = plural) or ovarian cells. Oogonia are diploid with 46 chromosomes or 23 pairs of chromosomes. Oogonia will reproduce themselves by mitosis to form primary oocytes.
Oogenesis has been started when a girl is still in the womb, that is when the baby was about 5 months in the womb.
By the time a baby girl 6 months old, primary oocyte will divide in meiosis. However, the first stage of meiosis in primary oocytes was discontinued until the baby girl grow up to be girls who experienced puberty. Primary oocytes are in a state of rest (dormant).
At the time the baby girl was born, in each of her ovaries contain about 1 million primary oocytes. When he reached puberty, the girl had only about 200 thousand primary oocytes only. While other oocytes degenerate during growth.
As puberty, girls will experience hormonal changes that cause primary oocytes resume meiosis first stage. Oocytes undergoing meiosis I would produce two cells that are not equal in size. First Tues merupaakn oocyte oocyte normal size (large) called the secondary oocyte, while cells that are smaller called the first polar body (primary polosit).
Furthermore, the secondary oocyte meiotic stage II continued (second meiosis). However, in meiosis II, the secondary oocyte does not directly resolved until the final stage, but stopped until ovulation occurs. If no fertilization occurs, the secondary oocyte will degenerate. But if there is sperm into the oviduct, meiosis II in the secondary oocyte will resume again. Finally, the oocyte meiosis II in the secondary will produce a large cell called ootid and one small cell, called the second polar body (polosit secondary). The first polar bodies are also split into two second polar bodies. Finally, there are three polar bodies and one ootid that will grow into an ovum from each one oogenesis oogonia.
Oocytes in oogonia are in an egg follicle. Egg follicles (follicles) is a cell full of liquid packaging menglilingi ova. Follicle functions to provide a food source for the oocyte. Follicles also changed along with changes in the primary oocyte secondary oocyte until ovulation occurs. Primary follicles appears first for primary oocyte surrounded. During meiosis I in the primary oocyte, primary follicles develop into secondary follicles. Formed during the secondary oocyte, secondary follicles developed into tertiary follicles. At the time of ovulation, the follicle developed into a tertiary follicle de Graaf (mature follicles). Once separated from the secondary oocyte follicle, the follicle changes into the corpus luteum. If not terjaid fertilization, the corpus luteum into the corpus will contract period albikan.Siklus
Menstruation (periods) is the periodic bleeding from the uterus and the cyclic release accompanied the endometrium. Menstruation occurs when an ovum is not fertilized by sperm. Menstrual cycle approximately 28 days. Release of an ovum in the form of a secondary oocyte from the ovary is called ovulation, which is related to the existence of cooperation between the hypothalamus and the ovary. The results of such cooperation would spur spending hormones that affect the menstrual cycle mechanism.
To simplify the explanation of the menstrual cycle, the existence of standards is a very important event, namely ovulation. Ovulation occurs in mid-cycle (½ n) menstruation. For the period or the first day of the menstrual cycle, ovulation occurs on day 14 counted from the first day of menstruation. Menstrual cycles are grouped into four phases, namely the menstrual phase, pre-ovulatory phase, ovulation phase, post-ovulatory phase.

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