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50 Cards in this Set
- Front
- Back
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The duration of an adult reproductive cycle, from the beginning of one menses to the beginning of the next menses, averages approximately 28 days, with a range of 23 to 35 days, and comprises three distinct phases. they are?
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The follicular phase begins with the onset of menses (the first day of the menstrual cycle) and ends on the day of the luteinizing hormone (LH) surge. Ovulation occurs within 30-36 hours of the LH surge. The luteal phase begins on the day of the LH surge and ends with the onset of menses. The follicular and luteal phases each last approximately 14 days in reproductive-age women; however, variability in cycle length is more frequent at the extremes of the reproductive age. The duration of the luteal phase remains relatively constant, while the duration of the follicular phase can vary.
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The duration of an adult reproductive cycle, from the beginning of one menses to the beginning of the next menses, averages approximately 28 days, with a range of 23 to 35 days, and comprises three distinct phases. they are?
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The follicular phase begins with the onset of menses (the first day of the menstrual cycle) and ends on the day of the luteinizing hormone (LH) surge. Ovulation occurs within 30-36 hours of the LH surge. The luteal phase begins on the day of the LH surge and ends with the onset of menses. The follicular and luteal phases each last approximately 14 days in reproductive-age women; however, variability in cycle length is more frequent at the extremes of the reproductive age. The duration of the luteal phase remains relatively constant, while the duration of the follicular phase can vary.
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When a woman is in a state of relative estrogen deficiency, as in the early follicular phase, the principal gonadotropin secreted is
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is FSH. The ovary responds to FSH secretion with estradiol production, with subsequent negative feedback on the pituitary inhibiting FSH secretion and positive feedback facilitating LH secretion.
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When a woman is in a state of relative estrogen deficiency, as in the early follicular phase, the principal gonadotropin secreted is
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is FSH. The ovary responds to FSH secretion with estradiol production, with subsequent negative feedback on the pituitary inhibiting FSH secretion and positive feedback facilitating LH secretion.
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When a woman is in a state of relative estrogen deficiency, as in the early follicular phase, the principal gonadotropin secreted is
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is FSH. The ovary responds to FSH secretion with estradiol production, with subsequent negative feedback on the pituitary inhibiting FSH secretion and positive feedback facilitating LH secretion.
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With ovulation, the ovarian follicle is converted into
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a corpus luteum and begins secreting progesterone.
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With ovulation, the ovarian follicle is converted into
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a corpus luteum and begins secreting progesterone.
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At birth, the human ovary contains approximately
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one to two million primordial follicles. Each follicle contains an oocyte that is arrested in prophase of the first meiotic division.
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At birth, the human ovary contains approximately
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one to two million primordial follicles. Each follicle contains an oocyte that is arrested in prophase of the first meiotic division.
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300,000 to 500,000 oocytes remain.
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menarche
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300,000 to 500,000 oocytes remain.
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menarche
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The immature oocyte is encircled by
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a single layer of granulosa cells, followed by a thin basement membrane that separates the follicle from the surrounding ovarian stroma.
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The immature oocyte is encircled by
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a single layer of granulosa cells, followed by a thin basement membrane that separates the follicle from the surrounding ovarian stroma.
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The immature oocyte is encircled by a single layer of granulosa cells, followed by a thin basement membrane that separates the follicle from the surrounding ovarian stroma. Early follicular maturation occurs independent of gonadotropins; the granulosa cells proliferate into multiple layers, and the surrounding stromal cells differentiate into
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theca cells
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The immature oocyte is encircled by a single layer of granulosa cells, followed by a thin basement membrane that separates the follicle from the surrounding ovarian stroma. Early follicular maturation occurs independent of gonadotropins; the granulosa cells proliferate into multiple layers, and the surrounding stromal cells differentiate into
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theca cells
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Granulosa cells produce
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estrogens, including estrone and estradiol, the latter being the more potent of the two.
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Granulosa cells produce
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estrogens, including estrone and estradiol, the latter being the more potent of the two.
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Theca cells produce
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androgens which serve as the precursors required for granulosa cell estrogen production. Androgens (androstenedione and testosterone) enter the granulosa cells by diffusion and are converted to estrogen.
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Theca cells produce
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androgens which serve as the precursors required for granulosa cell estrogen production. Androgens (androstenedione and testosterone) enter the granulosa cells by diffusion and are converted to estrogen.
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Theca cells produce
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androgens which serve as the precursors required for granulosa cell estrogen production. Androgens (androstenedione and testosterone) enter the granulosa cells by diffusion and are converted to estrogen.
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During follicular development
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FSH binds to FSHreceptors on the granulosa cells, causing cellular proliferation and increased binding of FSH and, hence, increased production of estradiol. Estradiol stimulates the proliferation of LH-receptors on theca and granulosa cells, and LH stimulates the theca cells to produce androgens. Greater androgen production leads to increased estradiol production. Rising estrogen levels influence the pituitary gland through negative feedback and results in suppression of
P.305 FSH and LH secretion. In the late follicular phase, peak estradiol concentrations from the dominant follicle have positive feedback on the pituitary, which stimulates the midcycle surge of LH secretion that is necessary for ovulation |
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During follicular development
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FSH binds to FSHreceptors on the granulosa cells, causing cellular proliferation and increased binding of FSH and, hence, increased production of estradiol. Estradiol stimulates the proliferation of LH-receptors on theca and granulosa cells, and LH stimulates the theca cells to produce androgens. Greater androgen production leads to increased estradiol production. Rising estrogen levels influence the pituitary gland through negative feedback and results in suppression of
P.305 FSH and LH secretion. In the late follicular phase, peak estradiol concentrations from the dominant follicle have positive feedback on the pituitary, which stimulates the midcycle surge of LH secretion that is necessary for ovulation |
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During follicular development
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FSH binds to FSHreceptors on the granulosa cells, causing cellular proliferation and increased binding of FSH and, hence, increased production of estradiol. Estradiol stimulates the proliferation of LH-receptors on theca and granulosa cells, and LH stimulates the theca cells to produce androgens. Greater androgen production leads to increased estradiol production. Rising estrogen levels influence the pituitary gland through negative feedback and results in suppression of
P.305 FSH and LH secretion. In the late follicular phase, peak estradiol concentrations from the dominant follicle have positive feedback on the pituitary, which stimulates the midcycle surge of LH secretion that is necessary for ovulation |
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when referring to the endometrium, the phases of the menstrual cycle are
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proliferative and secretory phases
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when referring to the endometrium, the phases of the menstrual cycle are
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proliferative and secretory phases
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when referring to the endometrium, the phases of the menstrual cycle are
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proliferative and secretory phases
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induce endometrial healing which leads to cessation of menstruation.
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Rising estrogen levels in the early follicular phase
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induce endometrial healing which leads to cessation of menstruation.
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Rising estrogen levels in the early follicular phase
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serum concentrations of estradiol, progesterone, and LH reach their lowest levels.
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At the end of the luteal phase
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serum concentrations of estradiol, progesterone, and LH reach their lowest levels.
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At the end of the luteal phase
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serum concentrations of estradiol, progesterone, and LH reach their lowest levels.
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At the end of the luteal phase
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begins to rise in the late luteal phase before the onset of menstruation to recruit the next cohort of follicles
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FSH
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begins to rise in the late luteal phase before the onset of menstruation to recruit the next cohort of follicles
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FSH
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Estradiol levels rise during the follicular phase, causing
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a decline in FSH.
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Estradiol levels rise during the follicular phase, causing
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a decline in FSH.
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LH starts to rise by the
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rise by the midfollicular phase
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LH starts to rise by the
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rise by the midfollicular phase
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Although several follicles begin the maturation process, only the follicle with
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the greatest number of granulosa cells and FSH receptors and the highest estradiol production becomes the dominant follicle; the nondominant follicles undergo atresia.
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The LH surge begins
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The LH surge begins 34 to 36 hours prior to ovulation, and peak LH secretion occurs 10 to 12 hours prior to ovulation. With the LH surge, the granulosa and theca cells undergo distinct changes and begin production of progesterone. Meiosis of the primary follicle resumes after the LH surge and the first polar body is released; the oocyte then arrests in metaphase of the second meiotic division until fertilization occurs.
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The LH surge begins
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The LH surge begins 34 to 36 hours prior to ovulation, and peak LH secretion occurs 10 to 12 hours prior to ovulation. With the LH surge, the granulosa and theca cells undergo distinct changes and begin production of progesterone. Meiosis of the primary follicle resumes after the LH surge and the first polar body is released; the oocyte then arrests in metaphase of the second meiotic division until fertilization occurs.
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The LH surge begins
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The LH surge begins 34 to 36 hours prior to ovulation, and peak LH secretion occurs 10 to 12 hours prior to ovulation. With the LH surge, the granulosa and theca cells undergo distinct changes and begin production of progesterone. Meiosis of the primary follicle resumes after the LH surge and the first polar body is released; the oocyte then arrests in metaphase of the second meiotic division until fertilization occurs.
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Meiosis of the primary follicle resumes after the LH surge and
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the first polar body is released; the oocyte then arrests in metaphase of the second meiotic division until fertilization occurs.
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Meiosis of the primary follicle resumes after the LH surge and
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the first polar body is released; the oocyte then arrests in metaphase of the second meiotic division until fertilization occurs.
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This withdrawal of progesterone releases
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This withdrawal of progesterone releases FSH from negative feedback, thus FSH levels begin to rise prior to menstruation and the initiation
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This withdrawal of progesterone releases
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This withdrawal of progesterone releases FSH from negative feedback, thus FSH levels begin to rise prior to menstruation and the initiation
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If the oocyte becomes fertilized and implantation occurs, the resulting zygote begins secreting human chorionic gonadotropin (hCG), which sustains the corpus luteum for anothe
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6 to 7 weeks.
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If the oocyte becomes fertilized and implantation occurs, the resulting zygote begins secreting human chorionic gonadotropin (hCG), which sustains the corpus luteum for anothe
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6 to 7 weeks.
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During the follicular phase, the rise in estrogen levels stimulates
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endometrial cell growth: the endometrial stroma thickens and the endometrial glands become elongated to form the proliferative endometrium. In an ovulatory cycle, the endometrium reaches maximal thickness at the time of ovulation.
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Progesterone causes differentiation
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of the endometrial components and converts the proliferative endometrium into a secretory endometrium. The endometrial stroma becomes loose and edematous, while blood vessels entering the endometrium become thickened and twisted. The endometrial glands, which were straight and tubular during the proliferative phase, become tortuous and contain secretory material within the lumen. With the withdrawal of progesterone at the end of the luteal phase, the endometrium breaks down and is sloughed during menses.
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Under the influence of estrogens, the endocervical glands
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secrete large quantities of thin, clear, watery mucus. Endocervical mucus production is maximal at the time of ovulation. This mucus facilitates sperm capture, storage, and transport.
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