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The Reproductive Systems

Terms in this set (58)

1. Days 1-5: Menstrual phase: in this phase, menstruation, the uterus sheds all but the deepest part of its endometrium.

-the thick, hormone-dependent functional layer of the endometrium detaches from the uterine wall, a process accompanied by bleeding for 3-5 days

-detached tissue and blood pass out through the vagina as the menstrual flow

-by day 5, the growing ovarian follicles start to produce more estrogen

2. Days 6-14: Proliferative (preovulatory) phase: in this phase, the endometrium rebuilds itself: Under the influence of rising blood levels of estrogens, the basal layer of the endometrium generates a new functional layer

-as this new layer thickens, its glands enlarge and its spiral arteries increase in number

-Consequently, the endometrium once again becomes velvety, thick, and well vascularized

-During this phase, estrogens also induce the endometrial cells to synthesize progesterone receptors, readying them for interaction with progesterone.

3. Days 15-28: Secretory (postovulatory) phase: this 14-day phase is the most constant timewise

-during the secretory phase the endometrium prepares for an embryo to implant

-rising levels of progesterone from the corpus luteum act on the estrogen-primed endometrium, causing the spiral arteries to elaborate and converting the functional layer to a secretory mucosa

-the endometrial glands enlarge, coil, and begin secreting nutrients into the uterine cavity that will sustain the embryo until it has implanted in the blood-rich endometrial lining.

-As progesterone levels rise, the cervical mucus becomes viscous again, forming the cervical plug, which helps to block entry of sperm and pathogens or other foreign materials.
-if no fertilization the corpus luteum degenerates toward the end of the secretory phase as LH blood levels decline progesterone levels fall, depriving the endometrium of hormonal support, and the spiral arteries kink and go into spasms spiral arteries constrict one final time and then suddenly relax and open wide blood gushes into the weakened capillary beds, they fragment causing the functional layer to slough off.

The uterine cycle starts over again on this first day of menstrual flow.
-FSH- regulation of the follicular phase and it effects the cells of the secondary and Graafian follicles; it causes follicular maturation and is secreted by the anterior pituitary

-LH: targets interstitial cells to produce androgens, stimulates the primary oocyte of the dominant follicle to complete its first division; it increases local vascular permeability, it stimulates the release of prostaglandins; it also triggers inflammatory response that promotes release of enzymes that help weaken the ovarian wall; it is also responsible for transforming that ruptured follicle into the corpus luteum; it is secreted by the anterior pituitary

-GnRH is secreted by the hypothalamus and it stimulates FSH and LH secretion

-Estrogen - secreted by the dominant follicle and the corpus luteum; it promotes development of reproductive structures; it promotes secondary sex characteristics; it supports the growth spurt it enhances HDL levels (good type of cholesterol); facilitates calcium uptake; increases protein anabolism and triggers LH surge

-Progesterone - secreted by the corpus luteum, it establishes and maintains the uterine cycle; it thickens cervical mucous; it helps prepare the breasts for lactation; it also decreases uterine contractions during pregnancy; it helps maintain stratum functionalis (what is sloughed off during menstruation and grows anew during each cycle); essential for maintaining pregnancy should it occur

-Inhibin - secreted by the granulosa cells and by the corpus luteum; it has negative feedback on the FSH and LH release (job is to inhibit)
FEMALE: find picture
-Tanner stage 1: pre-adolescent and see elevation of the nipple only; no pubic hair or breast development

-Stage 2: breast bud development; elevation of the breast and nipple becomes a small mound; sparse growth of long, slightly-pigmented downy hair along the labia

stage 3: further development of elevation of the breast and the areola (no separation of contours); darker, coarser, curlier hair that is spread over the pubic symphysis

-stage 4: projection of the areola, and the nipple projects with it to form a secondary mound; course and curly pubic hair as an adult would; covering more area than stage 3 but not as much hair as stage 5

-stage 5: mature stage, the projection of the nipple only, while the areola recedes to the general contour (nipple protrudes); quality and quantity of adult hair extends to the thighs, but not on the abdomen

MALE:

-stage 1: pre-adolescent, no pubic hair

-stage 2: sparse growth of long, slightly pigmented, downy hair at the base of the penis; penis has slight or no enlargement; testes and scrotum are larger, are reddened and altered in texture

-stage 3: darker, coarser, curlier hair, that spreads sparsely over the pubic symphysis; penis will enlarge in length, and testes and scrotum are also enlarged

-stage 4: this coarse curly hair is that of an adult, covering more than stage 3 but not as much as stage 5 and does not include the thighs; penis is enlarged in width and length with development of the glands; testes and scrotum are enlarged and become darker

-stage 5: quality and quantity of adult hair reaches the thigh but does not go onto the abdomen; penis, tests, and scrotum are adult size and shape