Development of the Male and Female Reproductive System Flashcards
*The reproductive system is composed of the ____ in male and ____ in female
testes, penis, and accessory glands
ovaries, uterus and vagina and vulva
The primordia of both male and female reproductive systems develop in the so- called ____ of devt.
indefferent stage
*The 1st indication of gonad formation is a swelling on the mesial side of the mesonephros called- ____
gonadal ridge
epithelial components form the ____
(primitive sex cords)
gonadal cord
*If the embryo is to become a male ( Y chromosome) , a male gonad develops in
the ____ of the of the gonadal ridge
*The gonadal cords form solid tubes which at birth become patent and form the _____
*These tubules are arranged in loops that are connected to the duct system, both are derivatives
medullary region
seminiferous tubules
*The primary germ cells in the gonadal cords become the ____ in
the definitive testis and in the ____
spermatogonia
mesonephric tubules
*If the embryo is to become a female, the epith. gonadal cords break up into many small clusters called ____
follicles
*In male, some parts of the mesonephros will give rise to the ffg.
efferent tubules (mesonephric tubules that fused with the gonadal cords)
epididymis (Mesonephric duct closely associated with the testis)
ductus deferens (Caudal part of the mesonephric duct)
*In female, the paramesonephric ducts become the ffg;
Fallopian tubes
Horn,body and cervix of the uterus
Part of the vagina
*Types of Uterus
has 2 uteri, characteristic of marsupials
Duplex
the body of the uterus is partitioned, found in some rodents and small ruminants
Bipartite
horns of the uterus are most prominent,found in pig,dog
Bicornuate
body is prominent,found in man
Simplex
*The formation of the external genitals also occur during the ____ where the mesoderm adjacent to the cloacal membrane creates a series of swellings:
indifferent stage
*external genitalia
mesoderm adjacent to the cloacal membrane creates a series of swellings: (3)
Genital tubercle
Urogenital fold
Genital swelling
mesodermal swelling at the cranioventral end of cloaca
Genital tubercle
fold lateral to the cloaca
Urogenital fold
mesodermal swellings located peripheral to the urogenital folds
Genital swelling-
*Fates of primordial structure in Male
Apex becomes glans penis
Remaining part – body of penis
Genital tubercle
*Fates of primordial structure in Male
fuse to form the penile urethra
Urogenital fold
*Fates of primordial structure in Male
become the scrotum which shift cranially,
closely apposed to the genital tubercle in
ox dog, horse and
Cat and pig –remains beneath the anus
Genital swelling
*Fates of primordial structures in Female
become the clitoris
Genital tubercle
*Fates of primordial structures in Female
become the labia or lips of the vulva
Urogenital fold
*Fates of primordial structures in Female
disappear in most species
In most mammals this canal closes, forming the tunica vaginalis.
- Ovaries descend as well, but come to rest in the pelvic cavity.
Genital swellings
Descent of testis in the inguinal canal occurs at:
106 dys
bull
70 dys
boar
*Descent of the gonads
Near birth
stallion
3-4 dys post natal
dog
At 35 dys testes are in the scrotum
dogs post partum
–failure of the testis to descend in the scrotum
Cryptorchidism
Both gonads arise high up on the body wall associated with the mesonephros, but then migrate posteriorly related to differential growth.
Descent of the Gonads
The testes pass down the posterior ____, behind the peritoneum, coming to lie in the forming scrotal pouches.
body wall
Covering the front of each ____ is the processes vaginalis, an extension of the peritoneal membrane.
testis
*In both sexes , develop from a pair of linear ectodermal ridge – ____ which are visible on the ventrolateral surface of the trunk between the levels of the limbs
mammary ridges
*Length of (mammary) ridges varies
reaches from axilla to the inguinal region, in what animals?
carnivores and swine
*Length of (mammary) ridges varies
limited only in the inguinal region, in what animals?
*ruminants and horse-
