Biology _ 3Sec_ menstrual cycle



menstrual cycle or menstruation this cycle occurs in the female human at puberty and is repeated every 28 days this is a period in which the ovary prepares an ovum alternating with the other ovary where an ovary can produce an ovum every 56 days the menstrual cycle starts with a bleeding for three to five days as a result of the degeneration of the endometrium and the rupture of blood vessels that found in the endometrium due to their uterine contractions this cycle takes 28 days and is divided into three stages which are stage of administration it occurs in the first five days of this cycle due to the degeneration of endometrial and the rupture of the blood vessels if the ovum is not fertilized second stage is their proliferation phase it starts in the sixth day from the beginning of the administration due to the hypersecretion of progesterone the anterior lobe of pituitary gland secretes their follicle stimulating hormone FSH that stimulates the ovary to form that the graafian follicle which contains the ovum the growth of graafian follicle takes about ten days and this follicle during its growth secretes estrogen hormone that stimulates the growth of the endometrium third stage if the ovulation fails due to the high post creation of estrogen hormone that is considered as an evidence of the ovum maturation the anterior lobe of pituitary gland squeeze the luteinizing hormone LH in the fourteenth day from the beginning of administration this hormone stimulates the release of the ovum from the graafian follicle and it's falling into the fallopian tube and the graafian follicle remains converted into the corpus luteum the corpus luteum secretes the progesterone hormone that increases the thickness of in Demetrio and its blood supply this phase remains about 14 days if the ovum is fertilized their pregnancies towards where the corpus luteum remains to secrete the progesterone hormone which inhibits the ovulation and the minstrel cycle stops to end all their pregnancy but in the case of unfertilized Asian of the ovum the secretion of progesterone decreases due to the shrinkage of the corpus luteum when reaching the day of 28 the endometrium degenerates and the blood vessels rupture causing the bleeding so the menstrual cycle repeats every 28 days where it starts and ends with bleeding therefore it is called by the menstruation period

Leave a Reply

Your email address will not be published. Required fields are marked *