Phys- reproductive

• 1.infundibulum: surrounds the ovary with fimbriae.  Efficient way to receive ova from ovary.
• 2. ampulla:  The middle, longest part of the tube. Usual location of fertilization.
• 3. isthmus:  Portion of tube that opens into uterus.

• The female external genitalia:
• the mons pubis
• labia majora
• labia minora
• clitoris
• vestibule of the vagina
• vestibular glands

• producing gametes (gametogenesis)
• - spermatozoa (sperm) in male
• -ova (eggs) in female

• testosterone in males
• estrogen and progesterone in females

• primary female reproductive organs
• produce ova (oogenesis)
• secrete female sex hormones (estrogen & progesterone)

• Essential for ova maturation and release
• Establishment of female secondary sexual characteristics
• Essential for transport of sperm from vagina to fertilization site in oviduct
• Contributes to breast development in anticipation of lactation

• Important in preparing suitable environment for nourishing a developing embryo/fetus
• Contributes to breasts’ ability to produce milk

• Undifferentiated primordial germ cells in fetal ovaries (precursor cells)
• Divide mitotically to give rise to 6 million to 7 million oogonia by fifth-7 month of gestation
• During last part of fetal life begin early steps of first meiotic division but do not complete it until puberty

they are prepared for ovulation

One chromosome replication followed by two nuclear divisions

a single layer of granulosa cells

primary follicle

• reach maturity and ovulate
• degenerate to form scar tissue (atresia)

secondary (antral) follicles on cyclic basis

• primary oocytes
• 46 chromosomes, each with 2 sister chromatids

mature haploid ovum

occurs in a fallopian tube after ovulation, but only after the secondary oocyte is fertilized

• 23 chromosomes, each with a single chromatid
• only ONE daughter cell, the ovum, will receive nearly all the cytoplasm

each primary oocyte can produce only one ovum

Primordial follicles, which consist of one primary oocyte surrounded by a single layer of cells called granulosa cells

• an increase in the size of the oocyte
• a proliferation of the granulosa cells into multiple layers
• separation of the oocyte from the inner granulosa cells by a thick layer of material, the zona pellucida

estrogen, small amounts of progesterone just before ovulation, and the peptide hormone inhibin.(inhibits FSH)

• differentiate and form layers, called theca
• the theca plays an imp role in estrogen secretion by the granulosa cells

the fluid-filled space called the antrum

• theca
• estrogen secretion

• during which a single mature follicle and secondary oocyte develop
• Where follicles are growing

beginning after ovulation and lasting until the death of the corpus luteum

TDF (testes determining factor) aka SRY protein

• genetic- depends on combination of sex chromosomes at time of conception
• ----this determines gonadal differentation
• gonadal- whether testes or ovaries develop, presence or absence of Y chromosome determines gonadal differentiation
• ---- gonadal determines phenotype
• phenotypic sex- apparent anatomic sex of individual, determined by gonadal sex

10-12 weeks

• androgens
• -testosterone is the most potent androgen

• Wolffian ducts-XY
• Mullerian ducts-XX

• female repro tract: absence of Mullerian-inhibiting factor
• dev of ext genitalia: absence of testosterone

• wolffian ducts: Mullerian inhibiting factor
• ext genitalia: testosterone converted to dihdrotestosterone

zona pellucida

• to secrete into the blood abundant quantities of progesterone and smaller amounts of estrogen
• also secretes inhibin

• "white body"
• if the secondary oocyte is not fertilized, the corpus luteum will degenerate and die. The vascular upply will be withdrawn, and connective tissue rapidly fills in to form a fibrous tissue mass-aka the corpus albicans

if fertilization does occur, the corpus luteum provides the hormones essential for maintaining pregnancy until the developing placenta can take over the function

• triggered by a positive feedback effect
• Rising moderate levels of estrogen early in the follicular phase inhibit LH secretion
• High level of estrogen that occurs during peak estrogen secretion late in follicular phase STIMULATE LH secretion & initiates the LH surge

• an increase in the size of the oocyte
• a proliferation of the granulosa cells into multiple layers
• separation of the oocyte from the inner granulosa cells by a thick layer of material, the zona pellucida.

• cytoplasmic processes that traverse the zona pellucida and form gap junctions with the
• oocyte

the theca, which play an important role in estrogen secretion by the granulosa cells.

A fluid-filled space, the antrum, begins to form in the midst of the granulosa cells as a result of fluid they secrete.

• LH--> thecal cells
• FSH --> granulosa cells

• cholesterol into androgen
• androgen into estrogen

• secreted into the blood where it exerts effects throughout body
• remains in the follicle and contributes to antral formation

estrogen comes from the thecal cells and the granulosa cells

a mound that projects into the antrum and is termed the cumulus oophorous

enzymatic digestion

the antral fluid

• Operates during first half of cycle
• Granulosa cells of some primary follicles proliferate
• Oocyte inside each follicle enlarges
• Theca cells in follicle secrete increased amounts of estrogen
• Rapid follicular growth continues during follicular phase
• ....One follicle usually grows more rapidly and matures about 14 days after onset of follicular development
• .......Follicle ruptures to release oocyte from ovary
• .......Event is called ovulation
• .......Released oocyte enters oviduct where it may or may not be fertilized

• Last 14 days of ovarian cycle
• Old follicular cells undergo structural transformation to form corpus luteum
• Becomes highly vascularized
• Becomes fully functional within four days after ovulation
• Continues to increase in size for another four or five days
• If released ovum is not fertilized and does not implant, corpus luteum degenerates within about 14 days after its formation
• ....Estrogen and LH  decrease

secrete more estrogen

45-55

climacteric or peri-menopause

• Characterized by discharge of blood and endometrial debris from vagina
• First day of menstruation is considered start of new cycle
• Coincides with end of ovarian luteal phase and onset of follicular phase

• Causes vasoconstriction of endometrial vessels
• ---Disrupts blood supply
• ---Causes death of endometrium
• Stimulates mild rhythmic contractions of uterine myometrium
• ---Help expel blood and endometrial debris from uterine cavity out  through vagina (menstrual flow)

• the ovarian follicular phase
• ---Endometrium starts to repair itself and proliferate under influence of estrogen from newly growing follicles
• Estrogen-dominant proliferative phase lasts from end of menstruation to ovulation
• Peak estrogen levels trigger LH surge responsible for ovulation

• Uterus enters this phase after ovulation when new corpus luteum is formed
• Corpus luteum secretes large amounts of progesterone and estrogen
• ---Progesterone
• -----Converts endometrium to highly vascularized, glycogen-filled tissue
• Endometrial glands actively secrete glycogen
• If fertilization and implantation do not occur
• ---Corpus luteum degenerates
• ---New follicular phase and menstrual phase begin once again

• normally occurs in upper third of oviduct (ampulla)
• 24 hrs
• 48 hrs, up to 5 days in female reproductive tract
• cervical canal, uterus, and to upper third of oviduct

• Contractions of myometrium
• Upward contractions of oviduct smooth muscle
• Allurin released by mature eggs attracts the sperm

zygote

blastocyst capable of implantation

• enzymes released by trophoblasts (outer membrane of blastocyst)
• enzymes digest the endometrial tissue; carving hole for implantation of blastocyst

cellular multiplication and implantation

• Organ of exchange between maternal and fetal blood
• Acts as transient, complex endocrine organ that secretes essential pregnancy hormones
•      –Human chorionic gonadotropin (placental hormone) (detects 9 days after implantation)
•         »Maintains corpus luteum until placenta takes over function in last two trimesters
•     –Estrogen & Progesterone
•         »Essential for maintaining normal pregnancy

the chorion

• Uterine enlargement
• Breasts enlarge and develop ability to produce milk
• Volume of blood increases 30%
• Weight gain
• Respiratory activity increases by about 20%
• Urinary output increases
• Kidneys excrete additional wastes from fetus
• Nutritional requirements increase

• Labor, delivery, birth
• requires:
• Dilation of cervical canal to accommodate passage of fetus from uterus through vagina and to the outside
• Contraction of uterine myometrium that are sufficiently strong to expel fetus

positive-feedback cycle

oxytocin secretion

• Causes stronger contractions
• Positive-feedback cycle progressively increases until cervical dilation and delivery are complete

• 1. Cervical dilation
• --Longest stage
• --Lasts from several hours to as long as 24 hours in a first pregnancy
• 2. Delivery of baby
• --Begins when cervical dilation is complete
• --Usually lasts 30 to 90 minutes
• 3. Delivery of placenta
• --Second series of uterine contractions separates placenta
• --Shortest stage – usually completed within 15 to 30 minutes after baby is born

4-6 wks

Elevated placental estrogen and progesterone

• Stimulates synthesis of enzymes essential for milk production by alveolar epithelial cells
• Withdrawal of placental steroids at parturition initiates lactation

• suckling
• oxytocin and prolactin

Causes milk ejection by stimulating cells surrounding alveoli to squeeze secreted milk out through ducts

Stimulates secretion of more milk to replace milk ejected as baby nurses