The cycle reproductive changes in females is marked my the menstrual cycle.during which some cells, unclotted blood from ruptured blood vessels, other fluids and the uterine endometrium is released through the cervix and vagina.
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The Menstrual Cycle 25 February 2003 George Beard The cycle reproductive changes in females is marked my the menstrual cycle.during which some cells, unclotted blood from ruptured blood vessels, other fluids and the uterine endometrium is released through the cervix and vagina. Each menstrual cycle occurs every 28 days and lasts for 4-5 days. an ovum is released from the ovary (ovulation) about once every 4 weeks. The menstrual cycle (of 28 days)
Menses occur when fertilization does not take place. (2) The proliferative (follicular) phase The proliferative phase occurs between the end of menses, and ovulation. In this phase, under the stimulation of estrogen, the uterine endometrium undergoes a process of growth (proliferation) and a new thick endometrium is formed. In the ovary, the follicle begins to develop into a Graafian follicle. This phase cycle days 6 to 13 or 14 in a 28 day cycle. (3) The ovulatory phase The ovulatory phase indicates the rupture of the Graafian follicle and release of the ovum (ovulation).
The endometrium which is under the influence of progesterone and estrogen, increases in size, becomes thick, the endometrial glands become enlarged, undergo maximum secretory activity and its blood vessels become coiled and enlarged These hormones regulate the menstrual cycle.These hormones have profound effects on the ovaries and the uterus. The anterior pituitary gland produces two gonadotrophic hormones: the follicle stimulating hormone (FSH) and the luteinizing hormone (LH). FSH stimulates the ovarian follicle to mature and secondly, it stimulates the follicle to produce estrogen. The estrogen brings about healing and repair of uterine wall (endometrium) following menstruation.
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