Reproductive System Pt.2 Flashcards
1
Q
Female reproductive system
A
■ Produces sex hormones and functional gametes
■ Protects and supports developing embryo
■ Nourishes newborn
2
Q
Ovaries
A
■ Are small, almond-shaped organs:
- near posterior walls of pelvic cavity
- 5 cm long, 2.5 cm wide, 8mm thick
-weigh 6–8 g
3
Q
Ovaries held in position by
A
Ovarian and suspensory ligaments of mesovaria
4
Q
Ovaries contains what type of follicle
A
Oocyte-containing follicles
5
Q
3 fictions of ovaries
A
■ Production of immature female gametes (oocytes)
■ Secretion of female sex hormones (estrogens, progestins)
■ Secretion of inhibin:
-feedback control of pituitary FSH
6
Q
Stroma
A
■ Are interior tissues of ovary:
-superficial cortex
-deeper medulla
■ Gametes are produced in ovaries
7
Q
Uterine tube
A
-supported by mesosalpinx
-extends from near ovary to uterus
-movements of its ciliated distal projections (fimbriae) along w/ peristalsis creates currents to help move ovulated locate in the uterine tube
8
Q
Uterine wall composed of:
A
-outer perimetrium
-myometrium
-inner endometrium
9
Q
Endometrium consists of:
A
-functional layer (stratum functionalis)
-sloughs off periodically unless an embryo has implanted
-underlying basal layer (stratum basalis)
-rebuilds functional layer
10
Q
Vagina
A
-extends from uterus to exterior
-copulatory organ
-allows passage of menstrual flow or baby
11
Q
Oogenesis
A
■ Also called ovum production
■ Begins before birth
■ Accelerates at puberty
■ Ends at menopause
12
Q
Atresia
A
■ Is the degeneration of primordial follicles:
■ Ovaries have about 2 million primordial follicles at birth:
-each containing a primary oocyte
■ By puberty:
-number drops to about 40,000
13
Q
Why are women more at risk for pid than men?
A
B/c duct system of women is incomplete- there is no physical connection between ovary and uterine tubes, which are open to the pelvic cavity.
In men, duct system is continuous from testes to body exterior
14
Q
Process of oogenesis
A
■ Primary oocytes remain in suspended development until puberty
■ At puberty:
-rising FSH triggers start of ovarian cycle
■ Each month thereafter:
-some primary oocytes are stimulated to mature further during menstrual cycle
15
Q
Oogenesis: 2 characteristics of meiosis
A
■ Cytoplasm of primary oocyte divides unevenly:
-producing 1 ovum (with original cytoplasm)
-and 2 or 3 polar bodies (that disintegrate)
■ Ovary releases secondary oocyte (not mature ovum):
-suspended in metaphase of meiosis II
16
Q
Locates are ovulated into the peritoneal cavity and yet women do get pregnant. What action if the uterine tubes helps to direct locates into woman’s duct system?
A
Waving action of fimbriae and currents created by beating cilia help to direct ovulated locates into uterine tube
17
Q
Ovarian follicles
A
■ Are specialized structures in cortex of ovaries:
-where oocyte growth and meiosis I occur
18
Q
Primary oocytes
A
■ Are located in outer part of ovarian cortex:
-near tunica albuginea
-in clusters called egg nests
19
Q
Primordial follicle
A
■ Each primary oocyte in an egg nest:
-is surrounded by 1 layer of follicle cells
■ immature oocyte and follicle cells form a primordial follicle (1 year before ovulation)
-different group of primordial follicles are activated each mo
20
Q
Vulva (fem genitalia) include:
A
-Mons pubis
-labia majors and minora
-clitoris
-urethral and vagina orficies
21
Q
Ovarian cycle: step 1
A
■ Formation of primary follicles:
-pre-granulosa cells become granulosa cells when multiple layers develop
Zona Pellucida
■ Region surrounding primary oocyte
■ Contains microvilli and glycoproteins
Thecal Cells
■ Surround follicle
■ Work with granulosa cells to produce estrogens
The Ovarian Cycle: Step 1
• Formation of primary follicles:
o follicle cells become granulosa cells when multiple layers develop
22
Q
What is female homologous of bulbo-urethral glands of males?
A
Greater vestibular glands
23
Q
Ovarian cycle: step 2
A
■ Formation of secondary follicles
■ Follicular fluid:
-accumulates between inner and outer layers of
follicle
24
Q
Ovarian cycle: step 3
A
■ Formation of a tertiary (mature Graafian) follicle:
-primary oocyte produces secondary oocyte and polar body
■ Secondary oocyte drifts free in antrum (expanded central chamber of follicle)
Corona Radiata
■ Granulosa cells associated with secondary oocyte
25
Cite similarities and differences between penis and citoris.
Both hooded by skin fold and are largely erectile tissue
Clitoris lacks corpus spongiosum containing urethra, so urinary and reproductive systems are completely separated in females
26
Tissues surrounding mammary glands
Adipose and fibrous connective tissue
27
Ovarian cycle: step 4
■ At ovulation:
■ tertiary follicle releases secondary oocyte with its corona radiata to peritoneal cavity
■ What remains is called the Corpus Hemorrhagicum
-It develops into the Corpus Luteum
28
Ovarian cycle: step 5
■ Formation of corpus luteum:
-produces steroid hormones progestins (progesterone) and some estrogen from cholesterol
■ Progesterone prepares uterine lining for pregnancy
29
Developmentally, mammary glands are modifications of certain skin glands. Which type?
Sweat glands
30
When does the glandular portion of breast develop in females?
Midway through pregnancy
31
Ovarian cycle: step 6
■ If fertilization does not occur
■ corpus luteum:
▪ degenerates about 14 days after ovulation
▪ fills with scar tissue to become corpus albicans
32
Uterine tubes
■ Fallopian tubes or oviducts
■ Are hollow, muscular tubes about 13 cm long
■ Transport oocyte from ovary to uterus
3 Segments of the Uterine Tube
■ Infundibulum:
-an expanded funnel near ovary
-fimbriae extend into pelvic cavity
■ Inner surfaces lined with cilia:
-beat toward infundibulum segment
33
3 segments of uterine tube
1.Ampulla:
-middle and longest segment
-smooth muscle layers in wall become thicker approaching uterus
2.Isthmus:
-a short segment between ampulla and uterine wall
3.infundibulum
34
Uterine tube structure
■ Epithelium lining uterine tube:
-contains scattered mucin secreting cells
■ Mucosa is surrounded by concentric layers of muscle
35
Oogenesis
Production of eggs
Begins in fetus
36
Oogonia
-Diploid stem cells that give rise to female gametes
-converted to oocytes before birth
37
Uterine tube and oocyte transport
■ Involves:
-ciliary movement
-peristaltic contractions in walls of uterine tube
-These processes are turned on by the ANS shortly before ovulation
■ It usually takes 3-4 days for the egg to reach the uterus
38
Meiosis
-puberty: meiosis resumes
-each mo, 1 primary oocyte completes meiosis I, producing secondary oocyte and tiny 1st polar body
-meiosis II or secondary oocyte produces functional ovum and 2nd polar body, but does not occur in less sperm penetrates secondary oocyte
-ovum contains most of primary oocytes cytoplasm. Polar bodies are nonfunctional and degenerate
39
Spermatogenesis vs Oogenesis
1 egg
4 sperm cells
40
Uterine tube and fertilization
■ For fertilization to occur:
-secondary oocyte must meet spermatozoa during first 12–24 hours – egg viable for 24hrs
■ Fertilization typically occurs:
-near boundary between ampulla and isthmus
41
Unfertilized oocytes
■ Degenerate in terminal portions of uterine tubes:
-or within uterus
42
Uterus
■ Provides for developing embryo (weeks 1–8) and fetus (week 9 through delivery):
-mechanical protection
-nutritional support
-waste removal
■ Is pear-shaped:
-7.5 cm long, 5 cm diameter
-weighs 30–40 g
■ Normally bends anteriorly near base (anteflexion):
-in retroflexion, uterus bends backward (20% incidence; no significance)
43
How do haploid cells arising from Oogenesis differ structurally and functionally from those arising from spermatogenesis.
Products of meiosis in females are 2 or 3 nonfunctional polar bodies (tiny haploid cells w/ essentially no cytoplasm) and 1 haploid ovum (functional gamete)
Meiosis in males yield 4 functional gametes, haploid sperm
44
3 suspensory ligaments of uterus
■ Uterosacral ligaments:
-extend from uterus to sacrum
-prevent inferior–anterior movement
■ Round ligaments:
-extend through inguinal canal
-end in connective tissues of external genitalia
-restrict posterior movement
■ Lateral (cardinal) ligaments:
-extend from base of uterus and vagina
-to lateral walls of pelvis
-prevent inferior movement
45
2 regions of uterus
■ Body
■ Cervix
The Uterine Body
■ Also called corpus
■ Is largest portion of uterus
■ Ends at isthmus
The Fundus
■ Is rounded portion of uterine body:
-superior to attachment of uterine tubes
46
What name is given to fluid-filled cavity of a vestibular follicle?
Antrum
47
The cervix
■ Is inferior portion of uterus
■ Extends from isthmus to vagina
■ Distal end projects about 1.25 cm into vagina
The Cervical Os
■ Also called external orifice of uterus
■ Is surrounded by distal end of cervix
■ Leads into cervical canal
The Cervical Canal
■ Is a constricted passageway opening to uterine cavity of body:
-at internal os (internal orifice)
48
Follicular phase of ovarian cycle
-1-14 days
-several vesicular follicles are rescued from atresia and continue to grow.
-only 1 per mo is selected to become
dominant follicle and completes maturation process
-late in this phase, oocyte in the dominant follicle completes meiosis I
-ovulation occurs about day 14, releasing secondary oocyte into peritoneal cavity, other developing follicles deteriorate
49
Cervical cancer
▪ 50,000 women/yr worldwide– killing half
▪ Most common between 30 – 50
▪ Risks – frequent cervical inflammations, STIs, multiple pregnancies
▪ Papanicolaou (Pap) smear for detection
-Every two years 21 – 30; every year > 30; discontinue at 65 if negative for 10 years
▪ Pap smear results inconclusive
-Test for human papillomavirus – cause of most cervical cancers
▪ Gardasil – three-dose vaccine; protects against HPV
-Recommended for 11- and 12-year-old girls
50
Blood supply of uterus
■ ranches of uterine arteries:
-arising from branches of internal iliac arteries
■ Ovarian arteries:
-arising from abdominal aorta
■ Veins and lymphatic vessels
Nerves of the Uterus
■ Autonomic fibers from hypogastric plexus (sympathetic)
■ Sacral segments S3 and S4 (parasympathetic)
■ Segmental blocks:
-anesthetic procedure used during labor
-target spinal nerves T10–L1
51
Literal phase of ovarian cycle
-ruptured follicle is converted to a corpus luteum, which produces progesterone and estrogens for the remainder of the cycle
-if fertilization does not occur, corpus luteum degenerated after about 10 days
52
Perimetrium
■ Is an incomplete serous membrane:
-continuous with peritoneal cavity
■ Covers:
-fundus
-posterior surface of uterine body and isthmus
53
Name and describe phases of one ovarian cycle and relate them to the events of oogenesis
Ovarian cycle has 2 parts - the follicular phase and the luteal phase. The follicular phase occurs from day 1-14 and the luteal phase from day 14-28 with ovulation occuring on day 14. During the folicular phase the follicle grows. It goes from the primordial follicle, to the primary follicle, to the secondary follicle, to the late secondary follicle, to the vesicular follicle. During the late secondary follicle phase, the zona pellucida develops and connective tissue (theca folliculi) work with granulosa cells to produce estrogens. Ovulation occurs after the oocyte is in the vesicular follicle. The walls of the follicle erupt and the oocyte is ejected. The luteal phase is the time in which the corpus luteum is active. Once the oocyte is ejected, the ruptured follicle collapses. The collapsed follicle is known as the corpus lutuem and it secretes estrogens and progesterones. If no fertilization occurs, the corpus luteum degenerates and becomes the corpus albicans. If pregnancy does happen, the corpus luteum produces hormones that sustains the uterus until the placenta develops.
54
Endometrium
■ Contributes about 10% of uterine mass
■ Glandular and vascular tissues support physiological demands of growing fetus
55
Uterine glands
■ Open onto endometrial cavity
-Simple columnar epithelium
■ Extend deep into lamina propria
-Areolar connective tissue
56
How do identical twins differ from fraternal twins?
Identical- develop from separation of a very young embryo (result of fertilization of single oocyte by single sperm) into 2 parts
Faternal- develop when different oocytes are fertilized by different sperm
57
Estrogen
Causes uterine glands, blood vessels, and epithelium to change with phases of monthly uterine cycle
58
Myometrium
■ The thickest portion of the uterine wall
■ Constitutes almost 90% of the mass of the uterus
Smooth Muscle in the Myometrium
■ Is arranged into longitudinal, circular (middle), and oblique layers
■ Provides force to move fetus out of uterus into vagina
■ Contractions stimulated by oxytocin
59
How long does establishment of cyclic pattern of hormone secretion, indicated by menarche take?
4 yrs
60
Leptin
-permissive role during puberty onset
-stimulates hypothalamus when adipose tissue is sufficient for energy requirements for reproduction
61
2 division of endometrium
■ Functional zone (stratum Functionalis):
-layer closest to uterine cavity
■ Basilar zone (stratum Basalis):
-adjacent to myometrium
62
Hormonal events of ovarian cycle:
1) GnRH stimulates anterior pituitary to release FSH and LH, which stimulate follicle maturation and estrogen production
2) when blood estrogens reach certain level, (+) feedback exerted on hypothalamic-pituitary-gonadal axis cause sudden release if LH that stimulates primary oocyte to continue meiosis of LG that stimulates the primary oocyte to continue meiosis and triggers ovulation. LH causes conversion of ruptured follicle to a corpus luteum and stimulates its secretory activity
3)rising levels of progesterone and estrogens inhibit hypothalamic-pituitary-gonadal (HPG) axis, corpus luteum deteriorates, ovarian hormones drop to their lowest levels, and cycle begins anew
63
Functional zone
■ Contains most of uterine glands
■ Contributes most of endometrial thickness
■ Undergoes dramatic changes in thickness and structure during menstrual cycle
64
Functional zone
■ Contains most of uterine glands
■ Contributes most of endometrial thickness
■ Undergoes dramatic changes in thickness and structure during menstrual cycle
65
Basilar zone
■ Attaches endometrium to myometrium
■ Contains terminal branches of tubular endometrial glands
66
Maturation of primordial follicle from its recruitment until it is ready to be ovulated takes how many days?
290
67
Maturation of primordial follicle from its recruitment until it is ready to be ovulated takes how many days?
290
68
Blood supply of endometrium
■ Arcuate arteries:
-encircle endometrium
■ Radial arteries:
-supply straight arteries (to basilar zone)
-supply spiral arteries (to functional zone)
■ spiral arteries are kept open by progesterone and estrogen
Cyclical Changes in Endometrium
■ Basilar zone remains relatively constant
■ Functional zone undergoes cyclical changes:
-in response to sex hormone levels
-produce characteristic features of uterine cycle
69
Blood supply of endometrium
■ Arcuate arteries:
-encircle endometrium
■ Radial arteries:
-supply straight arteries (to basilar zone)
-supply spiral arteries (to functional zone)
■ spiral arteries are kept open by progesterone and estrogen
Cyclical Changes in Endometrium
■ Basilar zone remains relatively constant
■ Functional zone undergoes cyclical changes:
-in response to sex hormone levels
-produce characteristic features of uterine cycle
70
Uterine cycle phases
-menstrual phase (days 0-4): functional layer sloughs off in menses
-proliferative phase (days 5-14): rising estrogen levels stimulate its regeneration.
-Under influence of both estrogens and progesterone during secretory phase (days 15-28): uterine glands secrete nutrients, and endometrial vascularity increases further
-
71
Uterine cycle phases
Repeated Changes in endometrium
-menstrual phase (days 0-4): functional layer sloughs off in menses
-proliferative phase (days 5-14): rising estrogen levels stimulate its regeneration.
-Under influence of both estrogens and progesterone during secretory phase (days 15-28): uterine glands secrete nutrients, and endometrial vascularity increases further
72
Falling levels of ovarian hormones during the last few days if ovarian cycle causes…
Spiral arteries to become spastic and cut off blood supply of functional layer. Uterine cycle begins again w/ menstruation
73
Menses
■ Is the degeneration of functional zone:
-occurs in patches
■ Is caused by constriction of spiral arteries:
-reducing blood flow, oxygen, and nutrients
■ Lack of Estrogen and Progesterone causes the release of prostaglandins which cause the spiral artery constriction
■ Weakened arterial walls rupture:
-releasing blood into connective tissues of functional zone
■ Degenerating tissues break away, enter uterine lumen
■ Entire functional zone is lost:
-through cervical os and menstruation
■ Only functional zone is affected:
-deeper, basilar zone is supplied by straight arteries
74
Proliferative phase (preovulatory)
■ Epithelial cells of uterine glands:
-multiply and spread across endometrium
-restore integrity of uterine epithelium
■ Further growth and vascularization:
-completely restores functional zone
-Occurs at same time as:
■ enlargement of primary and secondary follicles in ovary
-Is stimulated and sustained by:
■ estrogens secreted by developing ovarian follicles
■ Entire functional zone is highly vascularized
■ Small arteries:
-spiral toward endometrium
-from larger arteries in myometrium
Endometrial Glands
■ Manufacture mucus rich in glycogen:
1essential for survival of fertilized egg
75
Cervical mucus
■ from cervical mucosa
■ Thinner and more alkaline around ovulation
■ Thicker and harder for sperm to navigate
■ Supplemental energy source for sperm
■ May be involved in capacitation of sperm
76
Estrogen
-promotes oogenesis
-stimulates growth of reproductive organs and growth spurt and promote appearance of secondary sex characteristics
77
secretory phase (postovulatory)
■ Endometrial glands enlarge
■ Arteries of uterine wall:
-elongate
-spiral through functional zone
-Begins at ovulation
-Persists as long as corpus luteum remains intact
(Why?)
■ Peaks about 12 days after ovulation
■ Generally lasts 14 days
78
Progesterone
Cooperates with estrogens in breast maturation and regulation of uterine cycle
79
Estrogen major source
Ovary: developing follicles and corpus luteum
80
Estrogen Stimulus for release
FSH and LH
81
Estrogen effects in reproductive organs
Stimulate growth and maturation of reproductive organs and breast at puberty and maintain their adult size and function. Promote the proliferative phase of uterine cycle. Stimulate production of watery cervical mucus and activity if fimbriae and uterine tube cilia
Promote oogenesis and ovulation
During pregnancy, stimulate growth of uterus and enlargement of external genitalia and mammary glands
82
Estrogen promotion of secondary sex characteristics and somatic effects
Promote long bone growth followed by epiphyseal closure and feminization if skeleton (pelvis)
Inhibit bone reabsorption
Promote female pattern of fat deposit
83
Estrogen metabolic effects
Generally anabolic. Stimulate Na+ reabsorption by renal tubules, which inhibits diuresis
Enhance HDK (and reduce LDL) blood levels (cardiovascular sparing effect)
84
Estrogen neural effects
Along w/ DHEA (an androgen produced by adrenal cortex) are partially responsible for female libido
85
Progesterone major source
Ovary: mainly the corpus luteum
86
Progesterone stimulus for release
LH
87
Progesterone effects on reproductive organs
Cooperates we/ estrogen a in stimulating growth of breasts
Promotes secretory phase if uterine cycle
Stimulates production of viscous cervical mucous
Progesterone surge after ovulation enhances beating of cilia in uterine tube, promoting netting of sperm and oocyte
During pregnancy, quiets the myometrium and acts w/ estrogens to cause mammary glands to achieve their mature milk-producing state
88
Progesterone metabolic effects
Promotes diuresis (antiestrogenic effect)
Increases body temp
89
Progesterone metabolic effects
Promotes diuresis (antiestrogenic effect)
Increases body temp
90
Testosterone major source
Testes: Interstitial endocrine cells
91
Testosterone major source
Testes: Interstitial endocrine cells
92
Testosterone stimulus for release
LH
93
Estrogen feedback effects exerted
Both (-) and (+) feedback on gonadotropin release by the anterior pituitary and GnRH release by hypothalamus
94
Testosterone effects on reproductive organs
Stimulates formation of male reproductive ducts, glands, and external genitalia. Promotes descent of testes. Stimulates growth and maturation if internal and external genitalia at puberty; maintains their adult size and function
Required for normal spermatogenesis; ABP keeps its concentration high near spermatogenic cells
95
Progesterone feedback effects exerted
(-) feedback on gonadotropin release by anterior pituitary and GnRH release by hypothalamus
96
Testosterone promotion of secondary sex characteristics and somatic effects
Promotes (after conversion of estrogen) long bone growth followed by epiphyseal closure; promotes increased skeletal and muscle mass during adolescence. Promotes growth of larynx and vocal cords and deepening of voice. Enhances sebum secretion and hair growth, especially on face, axillae, genital region, and chest
97
Testosterone promotion of secondary sex characteristics and somatic effects
Promotes (after conversion of estrogen) long bone growth followed by epiphyseal closure; promotes increased skeletal and muscle mass during adolescence. Promotes growth of larynx and vocal cords and deepening of voice. Enhances sebum secretion and hair growth, especially on face, axillae, genital region, and chest
98
Testosterone feedback effects exerted
(-) feedback on gonadotropin release by anterior pituitary and GnRH release by hypothalamus
99
Testosterone metabolic effects
Anabolic
Stimulates hematopoiesis
Enhance basal metabolic rate
100
Testosterone neural effects
Responsible for libido in males
Promotes aggressiveness
101
Which hormone plays role in signaling brain that puberty may begin in girls?
Leptin
102
Which hormone promotes ovulation?
LH
103
Which gonadal hormones exert (+) feedback in anterior pituitary that results in burst like release of LH?
Estrogen
104
Which hormones cause secondary sex characteristics to appear in women?
Estrogen
105
Which gonadal hormones promote epiphyseal closure in both males and females, and what is the effect of epiphyseal closure?
Estrogens
Long bones stop growing in length when epiphyseal are ossified
106
Which glands help to lubricate vestibule?
Vestibular glands
107
STI
Spread via sexual contact; gonorrhea, syphilis, chlamydia (bacterial)
Trichomoniasis (parasitic)
Syphilis can infect organs throughout the body
108
Viral infection
Herpes and warts caused by HPV virus
Linked to cervical cancer
109
Gonads of both sexes arise from
Mesodermal gonadal ridges
110
Produce male accessory ducts and glands
Mesonephric ducts
111
Produce female duct system
Paramesonephric ducts
112
Why does only egg, rather than 4 eggs, developing during oogenesis?
Unequal cytoplasmic division ensures that a fertilized egg has ample nutrients for its journey to the uterus.
113
Formation of a secondary oocyte occurs during _
Follicular phase; during 1st meiotic division of oogenesis
114
Surge in _ directly triggers ovulation
LH
115
What even coincides w/ transition from proliferative phase to secretory phase?
Ovulation ovcurs
116
what ovarian structure forms at the beginning of the secretory phase, encouraging its progress and the degenerates just before menses?
Corpus luteum
117
During the secretory phase of uterine cycle, _
Endometrium prepares for implantation
118
During the secretory phase of uterine cycle, _
Endometrium prepares for implantation
119
what hormone produced in anterior pituitary works in conjuction with gonadal steroids to promote bone growth in males?
FSH
120
Round ligament
Anchors uterus and ovary
121
_ is shed during each menstrual and is then regenerated by the _
Functional layer of endometrium; myometrium
122
what layer of uterus is made of smooth muscle?
Myometrium
123
if an untrained person induces an abortion and severely puncture posterior vaginal wall, there is a potential risk if puncture wound extending onward into the wall of the _
Rectum
124
what part of breast produces milk?
Aveoli
125
Corpus Albicans
Fibrous scar tissue that was once corpus luteum that has since died from not getting signal from embryo
-result of fertilization not occurring
-cannot be stimulated by LH
-cannot produce progesterone
126
Endometrium layer
-stratum functionalis
-contains spiraled and could arteries
-stratum basalis
-contains straight arteries
127
Menstruation phase
Shedding of stratum functionalis and spiraled and coiled arteries
Days 1-5
128
Proliferation phase
-estrogen stimulates regeneration of S. functionalis and spiraled and coiled arteries
-days 6-14
-making of uterine glands
-thin cervical mucus production (allows sperm to pass)
129
Secretory phase
-progesterone stimulates…
-s. Functionalis becoming thicker
-spiraled and coiled arteries to become longer
-uterine gland to secrete nutrient-rich “broth” (contains glycogen, lipids, and proteins)
-formation of thick cervical mucus to prevent organism from entering (protecting potential embryo)
-days 15-28
