The oviducts are also called oviducts, indiatradezone formerly known as fallopian indiatradezone tubes are two tubes of great muscle mobility, belonging to the reproductive system of the female mammals, measuring approximately 12 cm in length, responsible for transporting the egg to the uterus. One end (the infundibulum) opens into the peritoneal cavity near the ovary and has extensions in the form of fringes, fimbriae calls; the other end (intramural) indiatradezone through the wall of the uterus and opens inside this organ.
Anatomically, the oviduct is divided into four parts: infundibulum, light bulb, isthmus and intramural. The medial portion of the tube, of smaller caliber, is the isthmus; indiatradezone the distal indiatradezone end of each tube is infundibulum, which opens near the ovary; adjacent the anterior portion is bulb; the intramural portion is uterine part, namely, forming the tube segment that is located in the wall of the uterus.
The wall of the oviduct is made up of three layers: a mucosal, a thick muscle layer of smooth muscle arranged on a circular inner layer and an outer longitudinal layer and a serous composed of a blade visceral peritoneum.
The mucosa has many folds arranged longitudinally that are too numerous inside the light bulb. In the lumen cross section of the ampoule resembles a labyrinth. These folds are lower in segments closest to the uterus tuba. In intramural region bends are reduced to small bumps and the inner mucosal surface is almost smooth. indiatradezone
The mucosa indiatradezone is formed by a simple columnar epithelium and lamina propria of loose connective tissue. The epithelium consists of two cell types, one is ciliated and the other is secretory. The cilia beat toward the uterus, moving in that direction a mucus film covering its surface. This liquid consists mainly of products of the secretory cells, which are interposed between the hair cells.
At the time of ovulation, fallopian tube plays an active movement and its tapered end approaches the ovarian surface, thereby facilitating the capture of the oocyte that is ovulated. The secretion has nourishing and protective indiatradezone functions regarding oocyte, and also promote the training of sperm.
Normally, fertilization occurs in the vial and reconstitute the diploid number of chromosomes typical of the species. Fertilization behaves as a stimulus for the oocyte to complete the second meiotic division, the end of which the primary oocyte becomes the secondary oocyte. The corona radiata, which typically involves the oocyte at fertilization is still preserved for a time during passing of the fallopian tube oocyte. Unless fertilized, the oocyte remains viable for up to 24 hours. If fertilization does not happen, the oocyte undergoes indiatradezone autolysis in the fallopian tube without completing the second indiatradezone maturation division.
After being fertilized, the oocyte comes to be named zygote, initiating a series of cell divisions and is transported to the uterus, a process which takes approximately 5 days. The contraction indiatradezone of smooth muscles and the activity of hair cells carry the oocyte or zygote along the infundibulum and the rest of the tube. This movement also prevents the passage of microorganisms of the uterus into the peritoneal cavity.
Sources: http://www.auladeanatomia.com/genitais/tubas.htm http://pt.wikipedia.org/wiki/Tuba_uterina http://www.saudeemmovimento.com.br/conteudos/conteudo_exibe1.asp?cod_noticia= 1220 Basic Histology - Luiz C. Junqueira and Jose Carneiro. Publisher Guanabara Koogan SA (10th Ed), 2004.
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