chapter 28: reproductive system Flashcards
1
Q
sex cell or it’s anatomical name are haploid?
A
gametes
2
Q
during meiosis I, homologous chromosomes undergo what process, where there form tetrads & exchange genes by crossing over?
A
synapsis
3
Q
why are testicles in a scrotum outside of the abdomen?
A
sperm development requires a lower temp than normal body temp.
4
Q
what is the condition in which the testes fail to descend through
the inguinal canal?
A
cryptorchidism
5
Q
each lobe of a testicle contains between 1 & 4 what which contain the stem cells for sperm production?
A
seminiferous tubules
6
Q
what interstitial cells of the testis produce?
A
androgens
7
Q
meiosis I in the process of spermatogenesis produces two what?
A
secondary spermocytes
8
Q
completion of meiosis produces four spermatids. How are these different from
spermatozoa?
A
round generic cells: must undergo spermatogenesis where chromosomes are compacted, excess cytosol & organelles are lost, and long flagellum is formed
9
Q
the bag of enzymes on the front of a sperm is called the what?
A
acrosome
10
Q
inhibin & androgen binding proteins are produced by what
cells?
A
sustentacular/ nurse
11
Q
what is the function of Mullerian inhibiting factor?
A
prevent development of uterus & uterine tubes (for males)
12
Q
where does sperm need approximately 20 days to mature?
A
epididymis
13
Q
list the passageway of sperm from the seminiferous tubule to the external
urethra orifice?
A
seminiferous tubule -> rete testis -> efferent ductule -> epididymis -> ductus deferens -> ampulla -> ejactulatory duct -> prostatic urethra -> membranous urethra -> spony/penile urethra -> external urethral orifice
14
Q
what is the purpose of the alkaline buffers in seminal fluid?
A
buffer acid in vagina to protect sperm
15
Q
pre-ejaculatory fluid is mostly produced by which gland?
A
bulbourethral
16
Q
what is the function of the enzymes in prostatic fluid?
A
digest cervical mucus to allow sperm entry into uterus & fibrinolysin to liquefy semen clot to release sperm in female reproductive tract
17
Q
what are the paired columns of erectile tissue that function to stiffen the penis?
A
corpora cavernosa
18
Q
what does parasympathetic innervation release to dilate arterioles in the erectile tissues?
A
nitric oxide (NO)
19
Q
why can anabolic steroid use by men lead to infertility?
A
testosterone provides negative feedback on GnRH from hypothalamus = FSH not released from anterior pituitary, no FSH = no stimulation of spermiogenesis in seminiferous tubules by sustentacular cells
20
Q
when a single layer of cells surrounds an oocyte they are called follicle cells, but once they are stratified they are called what cells?
A
granulosa
21
Q
completion of meiosis I produces one secondary oocyte & one what body?
A
polar body
22
Q
when are the primary oocytes in the primordial follicles created?
A
when the person with ovary had a fetus herself
23
Q
what’s the layer of cells that surrounds the secondary oocyte & travel with it after ovulation?
A
corona radiata
24
Q
the scar of a previous ovulated follicle that will be visible as the next ovarian cycle begins is called what?
A
corpus albicans
25
what are the finger-like extensions of the infundibulum that sweep the ovary surface for ovulated oocytes?
fimbriae
26
what is the layer of the uterine wall composed of smooth
muscle?
myometrium
27
during the proliferative phase, cells of what zone of the endometrium divide to grow new mucosa and glands?
basilar
28
what is the function of the glycogen secreted by endometrial glands?
feed a early embryo before it attaches to the blood supply
29
what is the function of the glycogen secreted by glands in the vagina?
feed lactic acids producing bacteria
30
what is the first menstrual cycle called?
menarche
31
what are the hairy skin folds of the lateral vulva that form the scrotum in the male?
labia majora
32
each lobule of the mammary gland empties the milk into what duct?
lactiferous
33
what is ovulation triggered by due to a sudden surge of the product?
luteinizing hormone
34
high levels of progesterone being secreted by the what triggers glandular secretion in the uterus and thickening of the cervical mucus?
corpus luteum
35
why is menses timed to be concurrent with the beginning of the follicular phase
of the ovary?
clear out old endometrial lining & grow a new one in time for ovulation so there's a fresh surface for potential embryo
36
menopause results in a marked decline in which two hormones?
estrogen & progesterone
37
gonads
primary sex organs, produce gametes
38
gametes
sex cells, ovum & sperm
39
somatic cells
all human cells, diploid (2n), 46 chromosomes, 23 homologous pairs
40
haploid cells (1n)
sex cells have half normal chromosome number (23 vs. 46)
41
gametogenesis
-process of gamete formation
-2n somatic cells produce 1n sex cells
-reducing chromosome number by half requires special cell division -> meiosis
42
mitosis events
-one 2n cell duplicates its DNA: each duplicated chromosome consists of two sister chromatids
-chromatids are separated equally turned into chromosomes
-two identical diploid daughter cells result
-process of cell division used by all somatic cells
43
meiosis events
-one 2n cell duplicates its DNA: each duplicated chromosome consists of 3 sister chromatids
-homologous chromosomes undergo synapsis: pair up forming tetrads (4 sister chromatids/ 2 duplicated chromosomes)
-homologous chromosomes exchange genes by cross-over
44
meiosis events pt.2
-in meiosis I homologous chromosomes separate (cells now 1n with duplicated chromosomes)
-in meiosis II sister chromatids separate (chromosomes) producing 4 haploids cells, all genetically different
-process of cell division only used for sex cell production
45
male reproductive system
-consists of male gonads = testes &
accessory reproductive organs = ducts,
glands, external genitalia that aid sperm production/ delivery
46
scrotum
-sac of cutaneous membrane, fascia, muscle
-external to abdominopelvic cavity
-maintains testes at optimal temp for sperm development (36.2°C/96.5°F)
47
raphe (scrotum)
each supports one testis and divides them
48
dartos muscle (scrotum)
-regulates temp.
smooth muscle in dermis, causes surface wrinkling to reduce heat loss
49
cremaster muscle (scrotum)
-regulates temp.
-skeletal muscle from
internal obliques adjust proximity of
testes to body
50
testes
-male gonads
-produce gametes (sperm) & hormones:
androgens (testosterone) & inhibin
51
testes development
-form in abdominal cavity: same tissue and
position as ovaries
-descend before birth through inguinal canal
52
cryptorchidism
failure of testes to descend, 3% full term 30% premature births,
internal testis will be sterile
53
inguinal hernia
protrusion of intestine
through inguinal canal
54
tunica vaginalis (testes structure)
derived from peritoneum: parietal & visceral layers
55
tunica albuginea (testes structure)
fibrous capsule of testis
56
testes structure
-partitions from tunica albuginea divide testis
into lobules
-each lobule contains 1-4 coiled seminiferous
tubules
57
seminiferous tubules converge into rete testis:
-> efferent
ductules (superior
and exterior to
testis) -> single
epididymis (coiled around outside of testis)
58
epididymis transmits sperm to ductus/vas
deferens:
connects testis to urethra
59
testes connected to abdominopelvic cavity by spermatic cords:
composed of CT surrounding ductus
deferens, blood and lymphatic vessels & autonomic nerves supplying testes
60
vasectomy
surgical sterilization: sever ductus deferens in spermatic cord
61
interstitial cell (functional regions of testes)
-in CT around seminiferous tubules
-produce androgens (testosterone)
62
seminiferous tubules (functional regions of testis)
-surrounded by capsule & areolar CT
-outer edge lined with spermatogonia (sperm
stem cell)
-spermatogonia divide & differentiate to
produce spermatozoa for release into lumen
-also contain sustenceullar cells
63
sustenceullar cells (seminiferous tubules -> functional regions of testis)
aid sperm differentiation, extend
from basement membrane to lumen
64
spermatogensis
sperm formation
-occurs in seminiferous tubules aided by sustentacular cells
-begin with spermatogonium
-as cells divide & differentiate they migrate toward lumen of tubule
*about 12 weeks
65
spermatogonium
stem cells of sperm, outer most tubule cell, contacts basement membrane
66
mitosis (spermatogonium -> primary spermocytes)
-spermatogonia divide producing daughter cells
-daughter cell A remains at basement membrane as spermatogonium (2n)
-daughter cell B differentiates into primary spermatocytes & moves toward lumen
67
meiosis (primary spermatocyte -> spermatid)
-diploid primary spermatocyte undergoes meiosis I to generate 2 haploid secondary spermatocytes
-secondary spermatocytes complete meiosis II producing 4 spermatids
68
spermiogenesis (spermatid -> sperm/ spermatozoa)
-round spermatids differentiate into small, streamlined motile cells at lumen: flagellum in formed, chromosomes are compacted, excess cytoplasm is shed
-takes ~5 weeks to complete
69
head (sperm structure)
-genetic part
-flattened nucleus, compact DNA
-covered by acrosome
70
acrosome (sperm head)
lysosome-like cap containing hydrolytic enzymes for ovum
penetration
71
midpiece (sperm structure)
-metabolic part
-contains mitochondria -> ATP to power contractile filaments of
flagella
72
flagellum (sperm structure)
-tail
-whip-like motion to propel cell
73
maintenance of blood -testis barrier (role of sustentacular cells in spermatogenesis):
cells linked by tight junctions regulate environment inside tubule ->
-high levels of androgens, estrogens,
K+, amino acids (testicular fluid)
-excludes leukocytes
74
support mitosis & meiosis (role of sustentacular cells in spermatogenesis):
stimulated by
FSH & testosterone,
promote cell
divisions
75
support during spermeogenesis (role of sustentacular cells in spermatogenesis):
hold spermatids & stimulate development
76
secrete inhibin (role of sustentacular cells in spermatogenesis):
peptide hormone-> inhibits FSH & GnRH (negative feedback for
spermatogenesis)
77
secrete androgen binding protein (role of sustentacular cells in spermatogenesis):
binds androgens to retain them in tubule
to stimulate spermiogenesis
78
secrete mullerian inhibiting factor (role of sustentacular cells in spermatogenesis):
prevent development of Mullerian ducts
(uterus, uterine tubes) in fetus
79
reproductive tract (males)
-spermatogenesis in seminiferous tubules takes 64-72 days
-immature sperm released into testicular fluid in lumen of tubule
-moved by fluid pressure &
cilia to epididymis
80
epididymis
-6m coiled tubule around top and side of testis
-during ejaculation, smooth muscle in wall propels sperm to ductus deferens
81
functions of the epididymis:
1. monitor & adjust composition of testicular fluid (stereocilia absorb or
secrete)
2. recycle damaged spermatozoa
3. protect, store, facilitate maturation of sperm:
-transit takes ~20d, sperm mature & gain ability to be motile
-mature sperm stored few months
82
ductus deferens
-passes through inguinal canal, anterior to pubis, loops over ureter, descends
posterior to bladder
-ends in ampulla
-during ejaculation, peristaltic contractions
transmit sperm from storage in epididymis to ejaculatory duct to mix with glandular secretions which activate sperm
-ejaculatory duct connects ampulla to urethra
83
ampulla
connects seminal vesicles & prostate
-ends ductus defrens
84
urethra (male reproductive tract)
-shared by
urinary & reproductive
system
- 3 regions: prostatic urethra, membranous urethra & spongy/penile urethra
85
prostatic urethra (urethra -> male reproductive tract)
connects to urinary
bladder & ejaculatory duct, passes through prostate
86
membranous urethra (urethra -> male reproductive tract)
passes through
body wall (urogenital diaphragm)
87
spongy/penile urethra (urethra -> male reproductive tract)
length of penis, opens at external urethral orifice
88
accessory organs of the male reproductive tract
produce fluid, nutrients, enzymes, buffers, that comprise bulk of semen
89
semen
- 2-5ml/ejaculation
- 60% seminal fluid
- 30% prostatic fluid
- 10% testicular fluid + active spermatozoa
- 50-300million sperm/ml
90
seminal vesicles
-on posterior bladder wall
-produce seminal fluid: fructose, prostaglandins, fibrinogen, vesiculase, alkaline buffers
-during ejaculation, sperm mixed with seminal fluid in ejaculatory duct becomes highly motile
91
fructose (seminal fluid -> seminal vesicles)
nutrients to drive sperm motility
92
prostaglandins (seminal fluid -> seminal vesicles)
promote smooth muscle contraction to aid sperm mobility
93
fibrinogen (seminal fluid -> seminal vesicles)
converted to fibrin to form clot in vagina
94
vesiculase (seminal fluid -> seminal vesicles)
enzyme for fibrinogen
conversion
95
alkaline buffers (seminal fluid -> seminal vesicles)
buffer acid pH of vagina
96
prostate gland
-encircles prostatic urethra
-secretes prostatic fluid into urethra:
1. enzymes to digest cervical mucus
2. fibrinolysin: breaks down semen clot to
release sperm in vagina
3. seminalplasmin: antibiotic
97
bulbourethral glands
-in urogenital diaphragm
-secrete alkaline mucus: neutralize urinary
acids and lubricate glans
98
sterile (male reproductive tract)
less than 60 million total sperm/ml
99
penis
functions to deliver sperm to the female reproductive tract
100
3 parts of the penis (penis -> external genitalia):
1. root- attaches to body wall
2. shaft- tubular, houses erectile tissue
3. glans- distal end, covered by prepuce
preputial glands secrete smegma
101
circumcision
remove prepuce: prevent UTIs
102
corpora cavernosa (shaft of penis -> external genitalia)
-2 columns of erectile tissue
-anterior, stiffen shaft
103
corpus spongiosum (shaft of penis -> external genitalia)
-1 column of erectile tissue
-surrounds urethra,
distal end forms glans,
holds urethra open
104
erectile tissue
vascular channels surrounded by elastic CT & smooth muscle, fills with blood via parasympathetic
stimulation
105
erection (male sexual function)
-triggered by tactile or mental stimuli
-parasympathetic triggers release of NO
-NO dilates arterioles -> blood fills channels
-expansion compresses drainage veins -> blood pressure = stiff
-parasympathetic also triggers secretion from
bulbourethral glands
-eventually spinal reflex triggered
106
ejaculation (male sexual function)
-spinal reflex -> sympathetic stimulation
-ducts & glands contract emptying contents to urethra
-skeletal muscles of penis contract, semen
propelled out urethral orifice
-25mph
107
detumescence (male sexual function)
-erection subsides: sympathetic constricts
arterioles
-latent period: new ejaculation not possible (min-hrs)
108
impotence
inability to achieve or maintain erection: due to alcohol, drugs, or
hormonal, vascular, or nervous system
problems
109
GnRH (hormone & male reproductive function)
- 1st step
-GnRH is released consistently in 60-90 minute intervals from the hypothalamus
-this triggers release of FSH & LH from the anterior pituitary
-consistent release of GnRH ensures that the circulating levels of all the hormones remain relatively constant
110
FSH targets sustentacular cells to (hormone & male reproductive function):
- 2nd step
-promote spermatogenesis
-promote secretion of androgen binding protein
-as spermatogenesis increases it triggers release of inhibin
-inhibin decreases GnRH & FSH by negative feedback
111
LH targets interstitial cells (hormone & male reproductive function):
-3rd step
-LH promotes the secretion of androgens (testosterone)
112
testosterone (hormone & male reproductive function):
-stimulates spermatogenesis (binds to androgen-binding protein)
-promotes sex drive in CNS
-simulates metabolism (especially skeletal muscle growth)
-establishes & maintains male secondary sex characteristics
-maintains accessory organs of the reproductive tract
-as levels increase, testosterone inhibits GnRH release by negative feedback
113
age-related changes (male reproductive tract)
-male climacteric:↓ testosterone = ↓ libido
-benign prostatic hypertrophy: prostate
↑, can block urethra
-↑ impotence
-sperm motility rate ↓
114
ovaries
-female gonads
-produce: gametes (ova) & hormones
estrogen, progesterone, inhibin
-lateral to uterus
-surrounded by two layers: tunica albuginea & germinal epithelium
-medulla contains blood vessels & nerves
115
accessory organs of female reproductive tract
uterus, uterine tubes, vagina
-aid fertilization, embryo growth & delivery
116
what is the germinal epithelium of the ovaries made from?
simple cuboidal
epithelium from peritoneum
117
what does the cortex of the ovaries house?
houses forming gametes in ovarian
follicles:
1. oocyte
2. surrounding cells:
-single layer = follicle cells
-stratified = granulosa cells
endocrine cells that produce female
sex hormones
118
oogenesis
oocyte formation
119
oogenesis process pt.1
-begins before birth & ends at menopause
-during fetal development primary oocytes suspended in meiosis I are formed in primordial follicles
-from puberty to menopause, primary oocytes are activated on a 28-day cycle (ovarian) to complete meiosis I to produce secondary oocyte & 1 small polar body
120
oogenesis process pt. 2
-at ovulation, the secondary oocyte is released from ovary suspended in meiosis II
-secondary oocyte won't complete meiosis to produce a mature ovum until fertilized by a sperm
121
formation of primary follicles (day 1-8) (follicular phase -> ovarian cycle ~28 days)
-squamous follicular cells of many primordial follicles enlarge into cuboidal cells -> dividing =
primary follicles
-the follicular cells produce stratified layers: now called granulosa cells
-microvilli from the innermost granulosa cells are connected to the primary oocyte via gap junctions to support & stimulate the growth of oocyte
-zona pellucida forms
-cells from the ovarian cortex form a layer of thecal cells around the outside of the primary follicle
-thecal cells & granulosa cells begin producing estrogens
122
zona pellucida (formation of primary follicles (day 1-8) -> follicular phase -> ovarian cycle ~28 days)
thick membrane around the primary oocyte that comes from secreted glycoproteins from granulosa cels
123
formation of secondary follicles (day 8-10) (follicular phase -> ovarian cycle ~28 days)
-only a few primary follicles continue development to become secondary follicles
-granulosa cells begin to secrete follicular fluid
-the fluid accumulates between the stratified layers of the granulosa cells creating a space called the antrum = secondary follicle
124
formation of 1 tertiary follicle (day 10-14)(follicular phase -> ovarian cycle ~28 days)
-the primary oocyte becomes restricted to one side of the follicle, attached by a stalk & surrounded by a layer of granulosa cells called the corona radiata
-the antrum continues to expand until the follicle spans the width of the cortex, this is now called a tertiary
follicle
-one tertiary or vesicular follicle usually forms (99% of the time)
-the primary oocyte completes meiosis I forming a secondary oocyte & small polar body
125
ovulation (day 14) (the ovarian cycle)
the tertiary follicle ruptures through the ovarian wall releasing the secondary oocyte surrounded by the zona pellucida
& corona radiata into the pelvic cavity
126
luteal phase (day 14-28) (the ovarian cycle)
-the ruptured tertiary follicle collapses & fills with blood
-the granulosa cells & thecal cells proliferate and reorganize into the corpus luteum
-the corpus luteum secretes progesterone & some estrogens
-if pregnancy does not occur the corpus luteum degenerates & is invaded by fibroblasts
-the fibroblasts create scar tissue called the corpus albicans
127
what happens when pregnancy occurs during the luteal phase of the ovarian cycle?
the corpus luteum remains active for 3+ months until the placenta takes over progesterone secretion
128
ovarian cycle at birth & puberty:
-at birth: ~2 million primordial follicles
-at puberty: ~200,000 remain
of those only ~500 will ovulate
129
uterine tube(s)
-muscular tube, lined with ciliated columnar
epithelium & mucin secreting cells
-oocyte moved via peristalsis & cilia
-secretions to nourish oocyte (& sperm)
-transit ovary to uterus takes 3-4 days
130
functions of the uterine tube(s):
-transmit oocyte to the uterus
-site for fertilization
131
3 regions of the uterine tube(s):
1. infundibulum - expanded end, has fimbriae with cilia that sweep ovarian surface to brush oocyte into uterine tube
2. ampulla - muscular length, fertilization
occurs here
3. isthmus - connects to uterus
132
ectopic pregnancy
implantation of zygote in location other than uterus (0.6%), most
spontaneously abort
133
uterus
-anterior to rectum, posterior & superior to bladder
-function: house & nourish fertilized ovum
-two regions: body & cervix
134
body of the uterus
-main portion, wall has 3 layers:
a. perimetrium = visceral peritoneum
b. myometrium: middle, thick muscular
c. endometrium: inner, glandular mucosa, simple columnar epithelium over thick lamina propria, 2 zones: functional & basilar
135
functional zone of the endometrium (body of uterus)
thick, borders uterine cavity, glands, vessels & epithelium change
with hormones through uterine cycle,
shed in menses
136
basilar zone of the endometrium (body of uterus)
thin, borders myometrium, remains constant, gives rise to new functional zone after menses
137
cervix (of the uterus)
-inferior, tubular
-connects to vagina through cervical canal
at external os
-mucosa has cervical glands: secrete thick
mucus to block canal to prevent infection (mucus thins at mid ovarian cycle for sperm entry)
138
prolapse of the uterus
damage to supporting
ligaments results in uterus protruding
through vaginal opening
139
uterine cycle (menstrual cycle)
corresponds with ovarian cycle; same hormones regulate both
140
menses (day 1-5) (menstrual cycle)
-correlates with beginning of follicular phase at ovary
-arteries constrict, tissues & glands of functional zone deteriorate
-menstruation occurs
141
menstruation
-necrotic vessels rupture, blood flushes necrotic endometrial tissue out of uterus to vagina
-loss of functional zone of endometrium
142
proliferative phase (day 6-14) (menstrual cycle)
-correlates with follicular enlargement & oocyte maturation
-cells of basilar zone of endometrium multiply to restore the mucosa, glands & vessels of the functional zone
143
secretory phase (day 15-28) (menstrual phase)
-correlates with ovulation & duration of luteal phase
-endometrial glands enlarge & secrete mucus rich in glycogen to nourish potential embryo
-secretion peaks 12 days post ovulation, then declines as corpus luteum ceases hormone production
144
what happens if a pregnancy occurs during the secretory phase of the menstrual cycle?
secretion will continue & menses will be inhibited
145
endometrosis
endometrial tissue growing outside uterus, painful mass that cycles, requires drugs or surgery
146
menarche
first menstrual cycle
147
menopause
last menstrual cycle
148
amenorrhea
failure to initiate menses, due to physical exertion & low body mass (leptin permissive on gonadotropins)
149
vagina
-functions to receive penis, deliver infants & menstrual flow
-elastic muscular tube, connects cervix to
vestible (external genitalia)
-epithelium secretes glycogen, resident
bacteria metabolize into lactic acid, low
pH prevents pathogen colonization
150
3 wall layers of the vagina:
1. adventitia
2. muscularis
3. mucosa: stratified squamous epithelium,
folded into rugae when relaxed
151
external genitalia of the female reproductive system
-"vulva"
- labia majora & minora, mons pubis, vestibule & clitoris
152
mon pubis (external genitalia of the female reproductive system)
anterior vulva,
adipose over pubic symphasis
153
labia majora (external genitalia of the female reproductive system)
lateral vulva
(=male scrotum),
surrounds labia
minora
154
labia minora (external genitalia of the female reproductive system)
encloses vestibule (=ventral penis)
155
vestibule (external genitalia of the female reproductive system)
urethral orifice anterior, vaginal orifice posterior, flanked by greater vestibular glands (=bulbourethal glands) that produce secretions to lubricate
vestible
156
clitoris (external genitalia of the female reproductive system)
anterior to vestibule, erectile tissue (=corpus cavernosa), covered by
prepuce
-formed by anterior labia
157
lactation
milk to nourish newborn
158
what is the center point of the mammary glands?
areola
-pigmented skin
around nipple
159
mammary glands
-modified sweat
glands over pectoralis
muscles
-divided into ~25 lobes around nipple, CT &
adipose between lobes
-lobe contains lobules of alveoli -> glandular
structures that produce milk
-lobule empties to lactiferous duct, exits lobe to lactiferous sinus
-sinus stores milk during nursing
-pregnancy causes proliferation of alveolar tissue for milk production
160
hormones & the female reproductive cycle
-ovarian & uterine cycles must be coordinated to allow fertilization & implantation of an embryo
-GnRH levels change for the cycles to alter the levels of FSH & LH which control the secretion of the female
sex hormones estrogen & progesterone
-sex hormone levels drive oocyte maturation & uterus development
161
follicular phase (hormones & the female reproductive cycle)
-GnRH levels begin to rise triggering release of FSH & LH
-granulosa cells of secondary follicles secrete inhibin which provides further negative feedback on FSH
162
FSH & LH stimulate follicle growth, maturation, production of estrogen (follicular phase → hormones and the female reproductive cycle):
-LH targets thecal cells to produce androstenedione
-FSH targets granulosa cells to convert this to estrogens
163
increasing estrogen levels trigger (follicular phase → hormones & female reproductive cycle):
-continued oocyte & follicle development
- growth of new functional layer in the uterus & expression of progesterone receptors on the endometrial tissue
-negative feedback inhibition on the release of FSH & LH
164
tertiary follicles are producing peak levels of estrogen which triggers (ovulation -> hormones & the female reproductive cycle):
-a burst of LH to be released (along with some FSH)
-thinning of the cervical mucus
165
the LH surge triggers (ovulation -> hormones & the female reproductive cycle):
-primary oocyte to complete meiosis I forming the secondary oocyte
-ovulation: rupture of the secondary oocyte through the ovary wall
-formation of the corpus luteum from the damaged tertiary follicle
166
luteal phase (hormones & the female reproductive cycle) pt.1
-the corpus luteum secretes progesterone, estrogen & inhibin
-increasing levels of progesterone trigger glandular secretion in the uterus & thickening of the cervical mucus
-all three luteum hormones (progesterone, estrogen, inhibin) act to provide negative feedback inhibition on LH, FSH & GnRH production and release
167
luteal phase (hormones & the female reproductive cycle) pt.2
-as LH levels decline, the corpus luteum begins to degrade forming the corpus albicans & luteum hormone secretion
ceases
-declining levels progesterone & estrogen trigger the initiation of menses
-decreased levels of all 3 luteum hormones no longer provide negative feedback: GnRH levels increase, and a new cycle begins
168
effects of estrogen
1. stimulate bone & muscle growth
2. develop/maintain female secondary sex
characteristics
3. stimulate sex drive in CNS
4. maintain accessory glands & organs for
reproduction
5. initiates repair & growth of endometrium
169
female sexual function
-triggered by tactile or mental stimuli
-parasympathetic triggers engorgement of erectile tissue: clitoris, vaginal mucosa, breast & secretion by vestibular glands
-orgasm with smooth muscle contractions but mechanism poorly understood
170
age-related changes (female reproductive tract)
-menopause: menstruation & ovulation cease
due to lack of primordial follicles
-estrogen & progesterone levels ↓
-GnRH, FSH, LH ↑
-resulting hormone levels result in:
-reduction of uterus & breast (glands)
-osteopenia or osteoporosis
-cardiovascular disorders
