chapter 10- reproductive system (female)
muscularis of the vagina
- middle layer -consists of smooth muscle - the relaxation of this smooth muscle allows the vagina to stretch during sexual intercourse and during childbirth
myometrium
- middle layer of the uterus -consists of smooth muscle - during childbirth, the posterior pituitary gland secretes oxytocin, which causes the myometrium of the uterus to contract
adventitia of the vagina
- outer layer - consists of connective tissue
perimetrium
- outer layer of the uterus -consists of epithelial cells and connective tissue
endometrium
-inner layer of the uterus - further subdivided into 2 strata (sublayers) 1. stratum functionalis 2. stratum basalis
vulva
a collective name that refers to the external genitalia of a women mons pubis, labia majora, labia minora, clitoris
regulation of progesterone
a high blood concentration of progesterone inhibits the secretion of GnRH, FSH, and LH; without FSH and LH, an ovarian follicle does not develop and the corpus luteum never forms
mons pubis
a region of adipose tissue covered by skin and pubic hair that is located anterior to the pubic bone
functions of estrogen
a. estrogen causes the development of female primary sex characteristics b. causes the development of female secondary sex characteristics (high pitched voice, fat distribution in the breasts and hips, and reduced body hair) c. causes the stratum basilis of the uterus to proliferate in order to form a new stratum functionalis every month after menstruation
functions of the fallopian tubes
a. fertilization normally occurs here b. the fallopian tubes transport the ovum into the uterus - contraction of the muscularis of the fallopian tube moves the ovum (whether fertilized or not) down the fallopian tube and into the uterus
external structure of the uterus
a. fundus- the superior part of the uterus b. body- the middle and largest part of the uterus c. cervix- the inferior part of the uterus, continuous with the vagina
mammary glands
each breast consists of a mammary gland and surrounding adipose tissue - the mammary glands are modified sweat glands that produce milk (a process called lactation) in a women that has just given birth
labia majora
large folds of skin that are inferior to the mons pubis usually covered by pubic hair
function of progesterone
progesterone causes the endometrium of the uterus to become secretory in order to prepare for the possible implantation of a fertilized ovum -stimulates the endometrial glands to secrete various nutrients (sugars, proteins, and lipids)
vaginal orifice
region of the vagina where it opens up to the exterior in a virgin it is partially covered by a vascularized hymen
follicle stimulating hormone (FSH)
secreted by the anterior pituitary gland a. FSH stimulates the growth and development of the ovarian follicle b. FSH stimulates the ovarian follicle to produce estrogen
human chorionic gonadotropin (HCG)
secreted by the chorion surrounding the developing embryo, keeps the corpus luteum functional for about 3 months -estrogen and progesterone continue to be produced, which keeps the stratum functionalis attached to maintain pregnancy
progesterone
secreted by the corpus luteum of the ovary
gonadotropin releasing hormone (GnRH)
secreted by the hypothalamus in a pustule fashion causes the anterior pituitary gland to secrete FSH and LH
clitoris
- formed at the superior junction of the labia minora - consists of erectile tissue that fills with blood and becomes erect when a women is sexually aroused
mucosa of the vagina
- inner layer - consists of a layer of epithelial cells that line a lumen and an underlying layer of connective tissue - the epithelial cells of the mucosa are involved in the formation of vaginal fluid, which is released into the vaginal lumen (this vaginal fluid is acidic and reduces the growth of microbes)
ovulation (day 14)
- the anterior pituitary suddenly releases a huge amount go LH into the blood -This LH surge causes the mature follicle to undergo ovulation - the released ovum is then swept into the fallopian tube by the fimbriae
preovulatory phase (days 6-13)
- the hypothalamus increases its secretion of GnRH, which stimulates the anterior pituitary gland to increase its release of FSH and LH -FSH and LH stimulate the development of a new ovarian follicle -the new follicle secretes estrogen causing the stratum basilis to proliferate in order to form a new stratum functionalis
stratum basalis
- the layer of the endometrium that is below the stratum functionalis - a permanent layer whose cells can proliferate to form a new stratum functionalis every month after menstruation occurs - both the stratum functionalis and the stratum basalis consist of epithelial cells, heavily vascularized connective tissue, and endometrial glands
stratum functionalis
- the layer of the endometrium that lines the uterine cavity - in an unpregnant women, the stratum functionalis sheds every month as a part of menstruation - in a pregnant women, the stratum functionalis remains attached to the rest of the uterus and serves as the location where the fertilized ovum implants and develops into a fetus
ampulla
- the part of the fallopian tube that is between the infundibulum and the isthmus - fertilization normally occurs here
infundibulum
- the part of the fallopian tube that is closest to the ovary - contains fingerlike projections called fimbriae that sweep the ovulated ovum into the fallopian tube
Oogenesis
- the production of the ova in the ovaries - oogenesis starts before birth, comes to a hault during childhood, resumes at puberty, and continuous until menopause
menstrual phase (days 1-5)
- the stratum functionalis of the of the endometrium sheds due to low blood concentration of estrogen and progesterone - the detached stratum functionalis and the blood that comes along with it is called menses or menstrual fluid - on average a women releases about 50mL of menses
how does the ovarian follicle secrete estrogen as it develops in the ovary
-as a secondary follicle is developing into a mature graafian follicle, the theca cells produce a steroid called androstenedione - the granulosa cells then take up the androstenedione, convert it to estrogen, and then secrete the estrogen into the blood *after ovulation has occurred, the corpus luteum also secretes estrogen and progesterone into the blood
postovulatory phase (days 15-28)
-at the beginning of this phase, LH causes the corpus hemorrahagicum to develop into the corpus luteum - in addition the LH stimulates the corpus luteum to secrete estrogen and progesterone into the blood
secondary follicle
-develops from the primary follicle consists of a. ovum b. antrum- a fluid filled cavity that forms within the secondary follicle c. granulosa cells- several layers, the closest layer of granulosa cells that surrounds the ovum is now called the corona radiata; between the corona radiata and the ovum is a layer of glycoprotein called the zona pellucida; additional layers of granulosa cells line the antrum of the secondary follicle d. theca cells- the granulosa cells proliferate to form two outer layers
primary follicle
-develops from the primordial follicle -consists of an ovum that is surrounded by several layers of granulosa cells
mature (Graafian) follicle
-develops from the secondary follicle - the mature (Graafian) follicle is structurally similar to the secondary follicle; the only major difference is that the mature follicle is larger due to cell growth
function of the ovaries
-produce ova (eggs) each ovum is produced as part of a larger structure called an ovarian follicle -the ovaries produce estrogen and progesterone
labia minora
-small folds of skin that are between the labia majora -lack of pubic hair - the labia minora surround the vestibule, which is a space that contains the external urethral oriface and the vaginal oriface
3 internal layers of the uterus
1. endometrium (with stratum functionalis and stratum basalis) 2. myometrium 3. perimetrium
3 major external regions of the fallopian tubes
1. infundibulum 2. ampulla 3. isthmus
3 internal layers of the fallopian tubes
1. mucosa- inner layer, consists of a layer of epithelial cells that line a lumen and an underlying layer of connective tissue 2. muscularis- middle layer, consists of smooth muscle 3. serosa- outer layer, consists of epithelial cells and connective tissue
stages of oogenesis
1. once a month starting at puberty, one of the primordial follicles develop into a primary follicle 2. the primary follicle then develops into a secondary follicle 3.the secondary follicle subsequently develops into a mature (Graafian) follicle 4. the graafian follicle then splits open and releases its ovum (with surrounding zona pellucida and corona radiata) from the ovary; this process is called ovulation. The ovum is then swept into the fallopian tube 5. the remainder of the follicle (granulosa cells and theca cells) stays in the ovary and is now called the corpus hemorrhagium 6. the corpus hemorrhagium expands and then turns into the corpus luteum, which is yellow in color 7. the corpus luteum degenerates, forming a whitish mass of scar tissue called corpus albicans
regulation of estrogen
1. the hypothalamus secretes GnRH in a pustule fashion causes the anterior pituitary to secrete FSH and LH 2. The FSH and LH stimulate the development of an ovarian follicle while the ovarian follicle develops, estrogen is released and the blood concentration of estrogen increases 3. a high blood estrogen concentration inhibits the secretion of GnRH from the hypothalamus and the secretion of FSH and LH from the anterior pituitary
how many total ova are ovulated throughout a women's entire reproductive life
450
how does FSH stimulate the ovarian follicle to produce estrogen
FSH causes the granulosa cells of the secondary follicle and mature (Graafian) follicle to take up androstenedione from the theca cells, convert it to estrogen, and then secrete estrogen into the blood
luteinizing hormone (LH)
LH is secreted by the anterior pituitary gland a. stimulates the growth and development of the ovarian follicle b. LH stimulates the ovarian follicle to produce estrogen c. LH causes ovulation to occur d. LH causes the corpus luteum to form e. LH stimulates the corpus luteum to secrete estrogen and progesterone into the blood
functions of the uterus
a. in an unpregnant women, menstruation occurs in the uterus b. in a pregnant women, the uterus is the location where the fertilized ovum implants and develops into a fetus c. during childbirth, the uterus contracts in order to push the fetus out of the women's body
functions of the vagina
a. the vagina is the female organ of sexual intercourse b. the vagina is a passageway for the release of menstrual fluid from the uterus to the outside environment c. the vagina serves as the birth canal, allowing the fetus to move from the uterus to the outside environment
uterus
also called the womb a pear shaped organ located between the fallopian tube and the vagina
fallopian tubes
also called uterine tubes or oviducts a women has 2 fallopian tubes; each extends laterally from the uterus and comes close to, but doesn't actually touch, an ovary
ovarian follicles
before birth, the ovaries produce all the ovarian follicles that a women will ever have during her life. About 2 million are formed in each ovary of a female fetus, all of them are primordial follicles which are immature
primordial follicle
consists of an ovum that is surrounded by a layer of granulosa cells -the ovum contains a nucleus which is haploid
bulbospongiosus muscle
deep to the vulva - during sexual intercourse, the rhythmic contraction of the bulbospongiosus muscle causes a women to have an orgasm
estrogen
depending on the stage of the female reproductive cycle, estrogen is secreted by the secondary follicle, mature follicle, or corpus luteum
Ovaries
the female gonads paired glands that are shaped like almonds the ovaries are held in place by various ligaments
isthmus
the narrow part of the fallopian tube that connects with the uterus