ANP 1107 - Female Reproductive System Flashcards
Ovarian Ligament
- Anchors ovary medially to the uterus
Suspensory Ligament
- Anchors it laterally to pelvic wall
- Broad ligament
Mesovarium
- Suspends the uterus between
- Broad ligament
Broad Ligaments
Peritoneal fold that “tents” over the uterus and supports the uterine tubes, uterus, and vagina
Ovarian Arteries
- Branches of the abdominal aorta and the ovarian branch of the uterine arteries
- Blood vessels reach ovaries via suspensory ligaments and mesovaria
Outer Cortex of the Ovaries
- Houses the forming gametes
Inner Medulla of the Ovaries
- Contains large blood vessels and nerves
Ovarian Follicles
- In the outer cortex
- Each one contains an immature egg
Oocyte
Immature egg
Fully Mature Vesicular
- Identified by its central fluid-filled cavity (antrum)
Fallopian Tubes
- Tube that the oocyte or egg passes from an ovary towards the uterus
- Where fertilization occurs
- 10 cm
Infundibulum
- Open funnel-shaped structure breaking ciliated fingerlike projections
Fimbriae
Finger like projections that drape over the ovary
What carries the egg
- Smooth muscles peristalsis
- Beating cilia
Tube
- Sheets of smooth muscle
- Thick highly folded mucosa (ciliated and non ciliated)
Microvili
- Produce secretions to keep the egg ( and sperm) warm moist and nourished
Uterus
- Located anterior to the rectum
- Posterior to the bladder
- Hollow thick walled muscle organ
Parts of the Uterus
- Fundus (top)
- Body (middle)
- Isthmus (middle to bottom)
- Cervix (Bottom)
Cervical Canal
- Cavity of the cervix
- Communicates with the vagina though external os and the cavity of the uterine body through the internal os
Cervical Mucosa
- Contains canal that contains cervical glands
- Glands secrete mucous
- Spots the spread to bacteria and blocks sperm
Uterine Wall: Perimetrium
- incomplete outermost layer
- serous
Uterine Wall: Myometrium
- Muscles of the uterus
- Middle Layer
- Smooth muscle
Uterine Wall: Endometrium
- Muscosal linning of the uterine cavity
- Simple columnar epithelium
- Underlain by thick lamina propria
- Fertilization occurs here
- Has two layers: Basalis and Functionalis
Blood Supply to the Uterine Wall
- Uterine ateries –> arcuate arteries ( in the myometrium)
- Radial ateries –> straight and coiled arteries (endometrium)
Vagina
- Thin walled
- 8 - 10 cm
- Passage way for baby, period, and penis
Layers of the vagina
(1) Outer fibroelastic : adventitia
(2) Smooth muscle : Muscularis
(3) Inner mucosa
Inner Mucosa of the Vagina
- Marked by transverse rugae
- Withstand friction
- Dendritic antigen-presenting cells
- No glands (lubricated by cervical mucosal glands)
- Acidic
Hymen
- Mucosal layer near vaginal office
- Vascularized
Vaginal Fornix
- Upper end of the vaginal canal, loosley surrounds the cervix
Mon Pubis
- Fatty rounded area
Labia Majora
- Posterior to the pubis
- Two elongated hair covered fatty skin folds
- Scrotum
Labia Minora
- Enclosed by the labia Majora
- Two thin hair free folds
- Penis
Vestibule
- “Entrance hall”
- Contains external openings
Greater Vestibular Glands
- Pea-sized
- On other side of the vaginal openings
Fourcette
- Extreme posterior end of vestibule, labia minor come together to form the ridge
Clitoris
- Anterior to the vestibule
- Protruding structure of erectile tissue
Two Parts:
(1) Glans of Clitoris: exposed portion
(2) Prepuce of Clitoris: formed by junction of the labia minora, richly innervated
Functions of the Ovaries
(1) Produce oocytes
(2) Produce reproductive hormones
Three Types of Steroid Hormones
- cross the membrane easily
- Progestins
- Androgens
- Estrogens
Progestins
- 21 carbons
- Produced by all major ovarian cell types
- Product of the Corpus lutem
- Menstrual cycle pregnancy
Androgens
- 19 carbons
- Precursors for synthesis of estrodial in developing follicle
- Synthesized by follicular theca cells and corpus luteum
Estrogens
- 18 carbons
- Synthesized by follicular granulosa cells and corpus luteum
- Essential for stimulation of follicular development, onset of puberty
FSH
Stimulates ovarian follicles to grow and produce estrodial
LH
Stimulates testosterone production by theca cells
- Stimulates ovulation, secretion of steroid hormones by corpus luteum
Hypothalamus
- Stimulates the secretion of FSH and LH via GnRH
Oogenesis
- Nuclear division of ovaries
Oogenesis: Fetal Period
- The oogonia (diploid sperm cell of the ovaries) multiply by mitosis
- Enter a growth phase and lay in nutrient reserves
- Gradually transformed into primary oocytes
- These oocytes begins its first meiotic division and stalls in prophase I
Oocyte Numbers Throughout Life
Birth: 7 million
Puberty: 250 0000
Age 30: 100 000
Age 50: Less than 5
Oocyte Activity around Menstruation
- Once a month one oocyte is selected to undergo meiosis
- Produces 2 haploid (23 chromosomes)
- These cells are different sizes
Polar Body
- Does not receive organelles
- Only little cytoplasm
- Undergoes meiosis II –? 2 smaller polar bodies
Second Oocyte
- Stops in metaphase !!
- Ovum is ovulated
Ovum Not Penetrated
- Ovum deteriorates
Ovum Penetrated
- Oocyte will complete meiosis II
- Yields one large ovum and a tiny polar body
Oogenesis: End Result
- Three tiny polar bodies
- One functional gamete
- Unequal division: ensures nutrients
Follicular Phase
- Period of growth
- 4 main stages
(1) Primordial follicle becomes primary follicle
(2) Primary follicle becomes secondary follicle
(3) Secondary follicle becomes a later secondary follicle
(4) Late secondary becomes becomes vesicular follicle
Follicular Phase: Primordial follicle becomes primary follicle
- Primordial follicle is activated
- Squamous cells surrounding the primary oocyte grow into cuboidal cells
- Now a PRIMARY FOLLICLE
Follicular Phase: Primary follicle becomes secondary follicle
- Follicular cells proliferate
- Form stratified epithelium around the oocyte
- More than one layer of cells = SECONDARY FOLLICLE
- Follicle cells = granola cells
Follicular Phase: Secondary follicle becomes a later secondary follicle
- Connective tissue condenses around the follicle, forming THECA FOLLICLE
- As follicle grows, theca cells make estrogen
- Oocyte forms the zona pellucida
- Liquid accumulates between cells, producing the late secondary follicle
Follicular Phase: Late secondary becomes becomes vesicular follicle
- Fluid between the granulosa coalesces
- Forms antrum
- Antrum makes it a vesicular follicle
- Antrum expands to isolate the oocyte
- Forms the corona radiate
- When follicle is 2.5 cm it bulges
Follicle Cells
- Granulosa Cells
- Connected by gap junctions
- Ions, metabolites, signally molecules pass through gap junctions
- Tell the oocyte to grow
- signal the oocyte not to complete meiosis
Bidirectional Conversion
- Occur between the oocyte and granulosa cells
Zona Pellucida
- Think transparent extracellular layer made of glycoprotien rich substance secreted by the oocyte
Antrum
- Fluid filled cavity
Corona Radiate
- Oocyte and surrounding capsule of granulosa
Ovulation
- Wall ruptures and expels the vesicular follicle
- Expelled into the peritoneal cavity
- One dominant follicle ovulates, triggering LH surge
- Other follicles undergo apoptosis
Luteal Phase: If fertilization does not occur
- Antrum fills with clotted blood (corpus hemorrahagicium)
- Eventually absorbed
- Granulosa cells increase in size –> Corpus luteum
- CL degenerates after 10 days
- Leaves the corpus albicans
Corpus Luteum
- Formed after ovulation
- Secretes estrogen and progesteron
Luteal Phase: If fertilization occurs
- CL persists until placenta takes over after three months
Establishing the Ovarian Cycle
- During childhood ovaries continuously secrete estrogen
- Inhibits release of GnRH
- Puberty: GnRH releases pulse-like
- AP releases FSH and LH
- GnRH increase for 4 years
- Leads to period
Hormones:
GnRH
- GnRH is secreted by the hypothalamus, stimulates production and release of FSH and LH from AP
Hormones:
FSH and LH
- Stimulate follicle growth, maturation, estrogen secretion
- FSH –> effect granulosa cells in late secondary
- LH –> targets thecal cells
- Follicles enlarge, thecal cells produce androgens
- Hormones diffuse through BM
- G cells convert to estrogen
Hormones:
Negative Feedback
- Rising estrogen –> negative feedback on hypo and AP
- Inhibits FSH and LH
- Pituitary accumulates gonatropins
- in overis, estrogen increases effects of FSH on follicle maturation
- Inhibin is released by granulosa cells
- neg, fb on FSH
- Dominant follicule survives
Hormones:
LH Surge
- High estrogen sets cascade of events
- Sudden burst of accumulated LH by AP midcycle
Hormones:
Ovulation
- Increased LH –> stimulates primary oocyte of dom. fol. to complete meiotic division
- Secondary oocyte continues to metaphase II
- LH stimulates ovulation
(1) increase vascular permeability
(2) release prostaglandins
(3) enzymes weaken ovary wall - Blood slops flowing through protruding part of the follicle wall
- Wall thins
- Estrogen levels will decline
Hormones:
Corpus Luteum Forms
- LH surge transforms ruptured follicle into CL
- Produces progesterone and estrogen immediately
- Progesteron helps maintain stratum functionalis
Hormones:
Negative Feedback Inhibits FSH and LH Release
- caused by rising estrogen in blood
- Inhibin released by CL enhances inhibitory
- Declining gonatropin level inhibit the development of new follicles, prevent LH surges (would cause more oocytes)
Hormones:
Non Fertile Cycles
- LH blood levels fall
- Stimulus for luteal activity ends
- CL degenerates
- Therefore decline in ovarian hormones and blood estrogen and progesterone level drops
- decline ends the blockade of FSH and LH, new cycle starts
Menstrual Cycle:
Day 1-5 : Menstrual Phase
- Uterus sheds
- Ovarian hormones at lowest
- Gonatropins begin to rise
- Endo detaches from UW
- Bleeding from day 3-5
- Day 5, ovarian follicles produce estrogen
Menstrual Cycle:
Days 6-14: Proliferative Phase
- Rising estrogen, endo rebuilds
- Basal generates new functionalis
- Layer thickens, glands enlarge, spiral arteries increase
- Estrogen –> progesterone receptors ready
- Estrogen thins mucous
- Ovulation –> sudden release of LH from AP
- LH converts follicle to CL
Menstrual Cycle:
Days 15- 28: Secretory Phase (General)
- Constant
- Endo prepares for implantation of embryo
- Progesterone forms CL
- Spiral arteries –> functional layer to secretory mucosa
- ## Endo glands enlarge, coil and secrete glycogen into uterine cavity
Menstrual Cycle:
Days 15- 28: Secretory Phase (Fertilization)
- Nutrients sustain embryo
- Increasing progesterone and estrogen
- -> cervical plug
- -> LH inhibited by AP
Menstrual Cycle:
Days 15- 28: Secretory Phase (No Fertilization)
- CP degenerates
- LH declines
- Progesteron falls, endo lack support
- Menstruation occurs
Puberty
- FSH and LH elevated at birth, fall, stay until puberty
- the period of life when reproduction organs grow to adult size and become functional
- changes due to rising gonadal hormones
Puberty: Male
- Androgens rise before testosterone surge
- Initiates:
- ->Hair growth
- ->Enlargement of testes and penis
- -> Sperm
Puberty: Females
- Budding breasts
- Ages 8-13
- Hair
Menopause
- Estrogen levels decline
- Lose control of ovulation
- Periods become irregular
Menopause: Effects
- boobs sag
- Vagina gets dry
- Vaginal infection increase
- Depression and irritability
- Vasodilatation (heat flashes)
- Thinning skin
- Weakened bones
- Cardiovascular
