Reproductive System II Flashcards
Female Reproductive System:
- Produces secondary oocytes
- Transports secondary oocytes to site where they can unite with sperm.
- Provides a suitable environment for development of the embryo and fetus.
- Actively involved in birthing process.
Structures of female reproductive system
- Paired ovaries –> produce female sex hormone.
- Paired uterine tubes –> which transports secondary oocytes.
- Uterus –> where development of the embryo and fetus occurs.
- Vagina –> serves as the female copulatory organ and birth canal.
- External Genitalia
Female Reproductive Tract contains:
1.uterine tubes
2. uterus
3. vagina
Ovaries
Located near the upper side walls of pelvic cavity
Outer surface is covered by the ovarian mesothelium
Under the mesothelium are ovarian follicles
The inner region has areolar connective tissue with nerves and blood vessels.
ovarian follicle consists of:
of an oocyte enveloped by supporting cells.
oogenesis
Process of producing oocytes
true or false: oogenesis is closely related to ovarian cycle
true
By what month of fetal development, do ovaries contain several million oogonia the stem cells of the ovaries (46 chromosomes)
5th month
oogonia
the stem cells of the ovaries (46 chromosomes)
true or false: Most of the oogonia mature into primary oocytes (46 chromosomes) prior to birth.
true
primordial ovarian follicle
primary oocyte surrounded by a single layer of follicular epithelial cells
true or false: females are born with their total number of primary oocytes
true, 2 mill.
true or false: Oogenesis exists at birth
false; No, oogenesis, the process of female gamete (egg cell) development, does not occur at birth. In fact, the process starts during fetal development in the ovaries of the female fetus. By the time a female baby is born, she already has all the primary oocytes (immature egg cells) that she will ever have. During puberty, a series of hormonal changes trigger the activation of some of the primary oocytes in a woman’s ovaries. This activation leads to the start of ovulation, where mature eggs are released from the ovaries in a cyclical manner, typically about once a month.
when does oogonia begin?
at puberty, a few primordial follicles are activated monthly and require nearly a year to mature.
How many primary oocytes complete meiosis I each month?
1
What happens prior to meiosis I with the primary oocyte?
chromosomes in primary oocyte replicate.
What happens during metaphase of meiosis I?
homologous pairs line up. Random alignment and crossover occurs.
What happens at the end of meiosis I?
primary oocyte divides into two distinct cells each with 23 chromosomes. polar body and secondary oocyte
True or false: polar body has an important function in the body?
false; no function; the secondary oocyte has nearly all the cytoplasm
When is the secondary oocyte released each month?
during a female’s reproductive life from the ovary at ovulation.
when will meiosis II only occur?
if secondary oocyte is penetrated by a sperm
how many cells does meiosiss II produce? are they different
yields 2 distinct cells, each with 23 chromosomes; polar body and ovum (all cytoplasm)
zygote
the first cell of the
preembryo. Fusion of ovum nucleus and
sperm nucleus
Uterine tubes
Each extends from laterally from upper side of the uterus to an ovary; receive and transport secondary oocyte; site of fertilization; Transport preembryo if fertilization occurs
infundibulum
partially envelops the
ovary; Possesses fimbriae
type of epithelium that lines the uterine tubes
simple ciliated
columnar epithelium and secretory cells
true or false: Beating cilia create a current to draw the secondary oocyte into the infundibulum
true
move oocyte toward uterus (movement)
cilia and peristalsis
Uterus
Behind the urinary bladder in pelvic cavity; above the vagina and bent forward over the urinary bladder
Uterus appropriate environment for?
developing embryo and fetus
3 regions of uterus:
- fundus
- body
- cervix
at what ages does cervical cancer usually occur?
30 - 50
Risks factors that increase cervical cancer
women who smoke
who began sexual activity at an early age who have histories of frequent sexually transmitted diseases
cervical inflammation
Pap smear
procedure in which loose cells are removed from the cervix and vagina then microscopically examined; look for cells with signs of dysplasia or carcinoma
cervical cancer caused by _______
human papilloma virus (HPV)
Pap smear recommendations for women between the ages of 21 to 65
one every 3 years
Wall of uterus composed of 3 layers
- Endometrium (Inner mucosal layer)
- Myometrium (Middle muscular layer-thicker layer of smooth muscle that forms most of the wall thickness.)
- Perimetrium (Outer serous layer)
Vagina
Collapsible tube extending from uterus to the external environment; Behind the urethra and in front of the rectum
function of vagina
- copulatory organ
- birth canal
females external genitalia (vulva)
Surrounds the orifices of the urethra and vagina
Perineum
Area between the mons pubis and the anus
Obstetrical perineum
between vaginal orifice and anus.
true or false: Obstetrical perineum is torn during childbirth
true
Labia Majora
Paired, longitudinal folds of hair-covered skin covering adipose and smooth muscle;
from what type of tissue is the labia major formed?
same as embryonic tissue as scrotum
Labia Minora
Paired, thinner longitudinal folds
Vestibule
Narrow space between the labia minora; Urethra opens into the front portion, while vagina opens behind it.
Bulbs of the Vestibule
Composed of corpus
spongiosum; Beneath the labia minora surrounding the beginning of the vagina.
what happens to the bulbs of the vestibule during a female sexual response?
Engorged with blood
vestibular glands
Lie behind the bulbs on each side of vaginal orifice and Release secretions into vestibule.
Clitoris
Formed of two columns of corpora cavernosa near the pubis
Glans of the clitoris
Union of the two columns of the
clitoris.
Located behind the mons pubis where the labia minora meet.
Abundant sensory receptors
In absence of sexual stimulation
Erectile tissues of bulb of the vestibule and clitoris have a small amount of blood
In the presence of sexual stimulation Parasympathetic action potentials
- Cause dilation of the arterioles and constriction of the venules supplying the erectile tissues to become engorged with blood and produce erection
- Cause enlargement of vaginal mucosa and breast and erection of nipples due to increase in blood flow in these areas.
Stimulate vestibular gland secretion to lubricate the vestibule
In the presence of sexual stimulation Sympathetic action potentials and prostaglandins in semen
trigger reverse peristalsis (cause the muscles to contract rhythmically) in pelvic floor muscles uterine wall, and uterine tubes. Aids in moving sperm through the uterus to the upper uterine tubes.
estrogens
Group of female sex hormones produced primarily by the ovaries
Estrogen is primarily produced by
ovarian follicles exposed to FSH and stimulate maturation of female reproductiveorgans
female secondary sex characteristics
Development of mammary glands and breasts.
Broad pelvis.
Increased subcutaneous tissue deposition
Increased blood supply to skin
Development of axillary and pubic hair (due to androgens)
progesterone
Produced by the corpus luteum (also releases estrogen) after ovulation under stimulation by LH; Major role is development and maintenance of endometrium in pregnancy; Also inhibits uterine contractions and dilation of the cervix during pregnancy
true or false: There are two cycles that are hormonally controlled and occur simultaneously starting at puberty
true: ovarian and menstrual
Ovarian cycle
Monthly formation and release of a secondary oocyte and the ovarian
events that occur in anticipation of pregnancy
Menstrual cycle
Repetitive changes in the endometrium that causes monthly menstruation if pregnancy does not occur.
length of females reproductive cycles
range from 24 to 35 days. 28 days is about average.
true or false: Cycles continue from puberty until menopause
true; (approx. 11 years of age); (between ages of 45 to 55).
when does reproductive cycle stop?
pregnancy and nursing.
When is the first menstruation
approx. age 13
when does the ovarian cycle begin?
when the hypothalamus secretes GnRH; release FSH and LH.
Follicular Phase
FSH promotes development of approx. 20 primordial ovarian follicles into primary ovarian follicles; where some primary develop into secondary ovarian follicle.
secondary ovarian follicle
transition into tertiary ovarian follicles with small fluid-filled spaces; each with a primary oocyte surrounded by granulosa cells.
Granulosa Cells
secrete estrogens and pass nutrients to developing oocyte.
Dominant tertiary ovarian follicle secretes _______.
low levels of estrogens and inhibin into the blood; Initiates a negative-feedback mechanism on GnRH and FSH.
Inhibition of FSH during ovarian cycle
prevents development of additional ovarian follicles.
due to increased FSH sensitivity granulosa cells —–
increase estrogen production ; beginning at dy 7 and peaking at day 12.