1 the proliferative phase the proliferative phase or

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1. The Proliferative Phase. The proliferative phase, or estrogen phase, is the first phase of the menstrual cycle when FSH causes 15 to 20 primary follicles to grow in the ovaries and when ovulation occurs. The Graafian follicle is an immature primary follicle that balloons into full maturity in the middle of the female’s menstrual cycle. The stigma is a small dot or nipple-like protrusion that develops on the surface of the Graafian follicle which causes the pituitary gland to release luteinizing hormone. The stigma disintegrates which causes the Graafian follicle to rupture and release an ovum. Ovulation is the release of a mature ovum by an ovary and occurs on or about the 14 th day before the expected beginning of the next menstrual period. 2. The Secretory Phase or Progestational Phase. The secretory phase, or progestational phase, is the second phase of the menstrual cycle, and during this phase the corpus luteum secretes progesterone and estrogen to prepare a female’s body for the implantation of a fertilized ovum. The corpus luteum is the yellow glandular body that is formed in the ovary from the follicular remains. Progesterone is a hormone secreted by the corpus luteum to initiate the nourishing secretions from the ovum in the fallopian tube, to inhibit the contraction of the muscular layer of the uterus, to stimulate the breasts’ ducts, and to thicken the uterine lining to receive the ovum. Estrogen and progesterone also inhibit the release of FSH and LH, so that no new primary follicles begin to mature. 3. The Menstrual Phase. The menstrual phase is the third phase of the menstrual cycle, and during this phase the corpus luteum degenerates, the secretion of estrogen and progesterone sharply decreases, and the menstrual flow occurs. The corpus luteum remains active for about 10 to 12 days, and if fertilization does not occur, the corpus luteum degenerates. The dead layer of cells separates from the rest of the uterus. The dead tissue and the small quantity of blood in the uterine cavity cause uterine contractions. Menstruation is the process by which the lining of the uterus is expelled each month that an ovum is not fertilized. 4. Menopause. Menopause is the cessation of the monthly menstrual cycle pattern as part of the natural process accompanying aging. Menopause occurs on average at age 51.
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During this time, the ovaries stop producing a monthly ovum. Without an ovum and without estrogen and progesterone, the lining of the uterus no longer builds up. Eventually, menstruation ceases entirely. Menopause might result from an oophorectomy. An oophorectomy is the surgical removal of the ovaries. There are two rather common symptoms that might accompany menopause – hot flashes and decrease in the moisture and elasticity of the vagina. Hot flashes are an indication that the body is trying to adjust to changing hormonal levels. Other symptoms that might accompany menopause include insomnia, headaches,
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  • Fall '12
  • Ms.Brunswich

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