The Female Reproductive System Flashcards
labioscrotal swellings
a pair of skin folds that form the scrotum in males due to presence of testosterone and forms the labia majora of the vagina in females due to absence of testosterone
urethral opening
where urine exits the body, located underneath the clitoris
labia minora
a pair of skin folds surrounding the urethral opening
uterus
hollow organ in the pelvic cavity into which the vagina opens up
cervix
the part of the uterus which opens into the vagina
endometrium
innermost lining of the uterus, responsible for nourishing a developing embryo and is shed during menstrual bleeding
myometrium
surrounds the endometrium, a thick layer of smooth muscle comprising the wall of the uterus
uterine tubes
aka fallopian tubes that extend into the pelvis from the uterus on each side that end in fimbriae
fimbriae
finger-like structures on the end of each uterine tubes
ovary
the female gonad, which brushes up against the fimbriae
the female sexual act
arousal (erection and lubrication controlled by parasympathetic nervous system), orgasm (sympathetic nervous system)-muscle contraction and cervix widening, no ejaculation, resolution (sympathetic nervous system)
greater vestibular glands
secretes mucus for lubrication along with vaginal epithelium
follicular phase
first phase of ovarian cycle, where a primary follicle matures and secretes estrogen (under control of FSH, lasts 13 days)
ovulatory phase
second phase of ovarian cycle, where a secondary oocyte is released from the ovary, triggered by LH surge which also causes remnants of the follicle to become corpus luteum (occurs on the 14th day)
luteal phase
third phase of ovarian cycle, begins with full formation of the corpus luteum in the ovary which secretes both estrogen and progesterone (14 days)
menstruation
first phase of uterine cycle, triggered by the degeneration of the corpus luteum and subsequent drop of estrogen and progesterone which causes bleeding (5 days)
proliferative phase
second phase of uterine cycle, estrogen produced by the follicle induces the proliferation of a new endometrium (9 days)
secretory phase
third phase of uterine cycle, after ovulation occurs, the estrogen and progesterone produced by the corpus luteum further increases the development of the endometrium, including secretion of glycogen, lipids, and other material.
human chorionic gonadotropin (hCG)
secreted by chorion portion of placenta (derived from trophoblast of blastocyst) and takes the place of LH in maintaining the corpus luteum to maintain elevated estrogen and progesterone levels
granulosa cells
supporting cells that surround the primary oocyte, secrete estrogen during the first half of the menstrual cycle
follicle
the structure consisting of the primary oocyte plus granulosa cells
primordial follicle
an immature primary oocyte surrounded by a single layer of granulosa cells
what changes do the primordial follicle undergo as it matures?
granulosa cells proliferate to form several layers around the oocyte and the zona pellucida forms
zona pellucida
a protective layer of mucopolysaccharides formed by the oocyte, layer located just outside egg membrane
thecal cells
cells that separate the follicles present in the ovary
the follicle that matures to the point of progressing to ovulation is termed the:
Graafian follicle (all other follicles degenerate)
corona radiata
the layer of granulosa cells surrounding the ovum (completed meiosis I) after ovulation/release into fallopian tube
corpus luteum
the structure formed in the ovary after ovulation from the remaining follicular cells
sperm capacitation
the dilution of inhibitory substances present in the semen to activate sperm, allows sperm to swim through the uterus towards the secondary oocyte
sperm is deposited at the:
cervix
fertilization
the fusion of a spermatazoan with the secondary oocyte, usually occurs in the uterine tube
acrosome reaction
release of hydrolytic enzymes in the acrosome by exocytosis to penetrate the corona radiata
acrosomal process
involves actin that elongates towards the zona pellucida and bindin (species-specific protein) that binds to receptors in the zona pelluica that allows sperm to penetrate zona pellucida
polyspermy
penetration of an ovum by more than one sperm
fast block to polyspermy
consists of a depolarization of the egg plasma membrane which prevents other spermatozoa from fusing with the egg cell membrane
slow block to polyspermy
results from a calcium influx caused by the initial depolarization, also known as the cortical reaction
what does the slow block/cortical reaction consist of?
swelling of the space between the zona pellucida and the plasma membrane, and hardening of the zona pellucida
what else does the calcium influx cause?
causes egg activation: increased metabolism and protein synthesis
in the blastocyst, the trophoblast becomes the
chorion (zygote’s contribution to placenta)
in the blastocyst, the inner cell mass becomes the
embryo, amnion, yolk sac, and allantois
the trophoblast secretes:
proteases the lyse endometrial cell and allows the developing blastocyst toe burrow and implant into the endometrium (allows for absorption of nutrients directly from endometrium)
placenta
organ that facilitates exchange of nutrients, gases, and even antibodies between the maternal and embryonic bloodstreams (takes 3 months to develop and then takes over maintenance of estrogen and progesterone levels)
placental villi
chorionic projections extending into the endometrium into which fetal capillaries will grow, surrounded by sinuses (open spaces) that fill with maternal blood
amnion
surrounds a fluid-filled (amniotic fluid) cavity which contains the developing embryo
yolk sac
in mammals, the first site of red blood cell synthesis
allantois
develops from the embryonic gut and forms the blood vessels of the umbilical cord, which transport blood between embryo and placenta
blastula
equivalent to blastocyst, a hollow ball of cells
gastrulation in primitive organisms involves:
invagination (involution) of blastula cells to form layers
archenteron
cavity of the primitive gut
blastopore
the opening that will eventually give anus
how does the gastrula develop in humans?
from a double layer of cells (embryonic disk) instead of a spherical blastula
ectoderm
entire nervous system, pituitary gland, cornea and lens, epidermis of skin and derivatives, nasal/oral/anal epithelium
mesoderm
all muscle, bone, and connective tissue, entire cardiovascular and lymphatic system, including blood, urogenital organs, dermis of skin
endoderm
GI tract epithelium, GI glands, respiratory epithelium, epithelial lining of urogenital organs and ducts, urinary bladder
differentiation
the specialization of cell types during development
determined
the point in the development of a cell at which the cell fate becomes fixed but before it is visibly differentiated
determination can be induced by:
cell’s environment or it can be preprogrammed
dedifferentiation
the process whereby a specialized cell unspecializes and may become totipotent
does differentiation involves genome change?
no, unless it is in the immune cell or gametes
totipotent
can generate trophoblast and inner cell mass (zygote, morula)
pluripotent
can differentiate into any of the 3 primary germ layers and thus generate all adult cell types (inner cell mass of blastocyst, embryonic stem cells, IPS cells-induced pluripotent stem cells)
multipotent
can produce many but not all cell types, more differentiated than pluripotent, often tissue-specific (three primary germ layers, adult stem cells)
dedifferentiation
some cells can go backwards and becomes less specialized (iPS cells, cancer cells)
first trimester
gastrulation, neurulation, organogenesis
second trimester
organs and organ system continue to develop structurally and functionally
third trimester
stage of rapid fetal growth, including significant deposition of adipose tissue, most of the organ systems become fully functional
